Home

ECV630-ECV749, CV735, CV26, CV745 Service Manual

1. KohlerEngines com A Oil Pan Seal B Oil Pan C Gerotor Gears D Oil Pump Assembly E Governor Shaft F Governor Washer G Governor Gear H Governor Cup l Crankshaft J Connecting Rod K Piston L Piston Pin M Piston E E N Piston Rings Governor Cross o Camshaft P Shaft Q Crankcase 99 Disassembly Inspection and Service Remove Camshaft Remove camshaft Inspection and Service Check lobes of camshaft for wear or damage See Specifications for minimum lift tolerances Measurement must be performed while valve train is still assembled Inspect cam gear for badly worn chipped or missing teeth Replacement of camshaft will be necessary if any of these conditions exist Remove Governor Cross Shaft 1 Remove retainer and nylon washer from governor cross shaft 2 Remove cross shaft through inside of crankcase Governor Cross Shaft Oil Seal Cross Shaft Oil Seal Details A 2 0 mm 0 0787 in B Governor Cross Shaft Seal If governor cross shaft seal is damaged and or leaks replace it using these following procedures Remove oil seal from crankcase and replace it with a new one Install new seal to depth shown using a seal installer Remove Connecting Rods with Pistons and Rings NOTE If a carbon ridge is present at top of either cylinder bore use a ridge reamer tool to remove it before attempting to remove piston NOTE Cylinders are
2. A Electrical Connection B Upper O ring C Solenoid Winding D Armature E Valve Housing F Valve Seat G Valve End H Lower O ring l Director Plate NOTE Do not apply voltage to fuel injector s Excessive voltage will burn out injector s Do not ground injector s with ignition ON Injector s will open turn on if relay is energized NOTE When cranking engine with injectors disconnected fault codes will be registered in ECU and will need to be cleared using software fault clear or an ECU Reset and TPS Learn Procedure Injector problems typically fall into three general categories electrical dirty clogged or leakage An electrical problem usually causes one or both of injectors to stop functioning Several methods may be used to check if injectors are operating 1 With engine running at idle listen for a buzzing or clicking sound 24 690 02 Rev E EFI SYSTEM ECV 2 Disconnect electrical connector from an injector and listen for a change in idle performance only running on one cylinder or a change in injector noise or vibration If an injector is not operating it can indicate either a bad injector or a wiring electrical connection problem Check as follows 1 Disconnect electrical connector from both injectors Plug a 12 volt noid light into one connector 2 Make sure all safety switch requirements are met Crank engine and check for flashing of test light Turn
3. A Tube B Washer C Armature D Drive E Stop F Retaining Ring G Collar H Drive End Cap I Screw J Plunger K Spring L Lever M Plate N Plug o Solenoid P Frame and Field Q Brush Holder R Nut S Commutator End T Screw Plate U Bolt When power is applied to starter armature rotates As armature rotates drive pinion moves out on drive shaft splines and into mesh with flywheel ring gear When pinion reaches end of drive shaft it rotates flywheel and cranks engine When engine starts flywheel rotates faster than starter armature and drive pinion This moves drive pinion out of mesh with ring gear and into retracted position When power is removed from starter armature stops rotating and drive pinion is held in retracted position by anti drift spring 86 KohlerEngines com Starter Disassembly NOTE Do not reuse old retainer NOTE Do not soak armature or use solvent when cleaning Wipe clean using a soft cloth or use compressed air 1 Remove nut and disconnect positive brush lead bracket from solenoid terminal 2 Remove screws securing solenoid to starter 3 Remove retaining ring from armature shaft using either a retaining ring pliers or snap ring removal tool as described in Steps 4 and 5 Do not reuse old retainer 4 Remove thru larger bolts 5 Remove commutator end plate assembly containing brush holder brushes springs and locking caps Remove thrus
4. RR z A LK e BSS S TESI i B Oil Pressure c A Oil Sentry Switch Oil Fill Dipstick D Oil Fill Tube E Oil Cooler F Oil Filter G OIL RECOMMENDATIONS Refer to Maintenance CHECK OIL LEVEL NOTE To prevent extensive engine wear or damage never run engine with oil level below or above operating range indicator on dipstick Ensure engine is cool Clean oil fill dipstick areas of any debris 1 Remove dipstick wipe oil off 2 Reinsert dipstick into tube rest cap on tube do not thread cap onto tube 3 Remove dipstick check oil level Level should be at top of indicator on dipstick 4 If oil is low on indicator add oil up to top of indicator mark 5 Reinstall and secure dipstick Back Side 78 KohlerEngines com CHANGE OIL AND FILTER Change oil while engine is warm 1 Clean area around oil fill cap dipstick and drain plug Remove drain plug and oil fill cap dipstick Allow oil to drain completely 2 Clean area around oil filter Place a container under filter to catch any oil and remove filter Wipe off mounting surface Reinstall drain plug Torque to 10 ft Ib 13 6 N m 3 Place new filter in shallow pan with open end up Fill with new oil until oil reaches bottom of threads Allow 2 minutes for oil to be absorbed by filter material 4 Apply a thin film of clean oil to rubber gasket on new filter 5 Referto instructions on o
5. e Breather reed broken e Clogged broken or inoperative crankcase breather e Loose or improperly torqued fasteners e Piston blow by or leaky valves e Restricted exhaust Troubleshooting EXTERNAL ENGINE INSPECTION NOTE It is good practice to drain oil at a location away from workbench Be sure to allow ample time for complete drainage Before cleaning or disassembling engine make a thorough inspection of its external appearance and condition This inspection can give clues to what might be found inside engines and cause when it is disassembled e Check for buildup of dirt and debris on crankcase cooling fins grass screen and other external surfaces Dirt or debris on these areas can cause overheating e Check for obvious fuel and oil leaks and damaged components Excessive oil leakage can indicate a clogged or inoperative breather worn or damaged seals or gaskets or loose fasteners Check air cleaner cover and base for damage or indications of improper fit and seal Check air cleaner element Look for holes tears cracked or damaged sealing surfaces or other damage that could allow unfiltered air into engine A dirty or clogged element could indicate insufficient or improper maintenance Check carburetor throat for dirt Dirt in throat is further indication that air cleaner was not functioning properly Check if oil level is within operating range on dipstick If itis above sniff for gasolin
6. 0 001 0 045 mm 0 039 0 0018 in Hydraulic Lifter to Crankcase Running Clearance 0 011 0 048 mm 0 0004 0 0019 in 0 0241 0 0501 mm 0 0009 0 0020 in Intake Valve Stem to Valve Guide Running Clearance 0 040 0 078 mm 0 0016 0 0031 in 0 038 0 076 mm 0 0015 0 0030 in Exhaust Valve Stem to Valve Guide Running Clearance 0 052 0 090 mm 0 0020 0 0035 in 0 050 0 088 mm 0 0020 0 0035 in Intake Valve Guide I D New Max Wear Limit Exhaust Valve Guide l D New Max Wear Limit 7 040 7 060 mm 0 2772 0 2780 in 7 134 mm 0 2809 in 7 040 7 060 mm 0 2772 0 2780 in 7 159 mm 0 2819 in 7 038 7 058 mm 0 2771 0 2779 in 7 134 mm 0 2809 in 7 038 7 058 mm 0 2771 0 2779 in 7 159 mm 0 2819 in Valve Guide Reamer Size Standard 0 25 mm O S 7 050 mm 0 2776 in 7 300 mm 0 2874 in 7 048 mm 0 2775 in 7 298 mm 0 2873 in Intake Valve Minimum Lift 8 07 mm 0 3177 in Exhaust Valve Minimum Lift 8 07 mm 0 3177 in Nominal Valve Seat Angle 45 3Values are in Metric units Values in parentheses are English equivalents 24 690 02 Rev E KohlerEngines com 13 Specifications GENERAL TORQUE VALUES English Fastener Torque Recommendations for Standard Applications Bolts Screws Nut
7. 16 995 17 000 mm 0 6691 0 6693 in 16 994 mm 0 6691 in 16 995 17 000 mm 0 6691 0 6693 in 16 994 mm 0 6691 in Top Compression Ring to Groove Side Clearance 0 050 0 095 mm 0 0019 0 0037 in 0 025 0 048 mm 0 0010 0 0019 in Middle Compression Ring to Groove Side Clearance 0 030 0 075 mm 0 0012 0 00307 in 0 015 0 037 mm 0 0006 0 0015 in Oil Control Ring to Groove Side Clearance 0 010 0 011 mm 0 0004 0 0043 in 0 026 0 176 mm 0 0010 0 0070 in Top and Middle Compression Ring End Gap New Bore 0 25 0 56 mm 0 010 0 022 in 0 25 0 56 mm 0 0100 0 0224 in Used Bore Max 0 80 mm 0 0315 in 0 94 mm 0 94 mm 0 037 in 0 037 in Thrust Face O D 79 962 79 980 mm 82 949 82 967 82 986 mm 3 2671 in 3 1481 3 1488 in mm 3 2657 3 2664 in Max Wear Limit 79 831 mm 82 818 mm 82 841 mm 3 2614 in 3 1430 in 3 2606 in Values are in Metric units Values in parentheses are English equivalents 7 Measure 6 mm 0 236 in above bottom of piston skirt at right angles to piston pin 12 KohlerEngines com 24 690 02 Rev E CLEARANCE SPECIFICATIONS Piston Thrust Face to Cylinder Bore Running Clearance New Valves and Valve Lifters ECV630 ECV680 ECV730 ECV749 Piston Piston Rings and Piston Pin continued 0 020 0 063 mm 0 0008 0 0024 in 0 0039 0 082 mm 0 0015 0 0032 in Specifications CV26 CV735 CV745
8. feature is programmed into ECU If maximum RPM limit 4500 is exceeded ECU suppresses injection signals cutting off fuel flow This process repeats itself in rapid succession limiting operation to preset maximum Engine speed sensor is essential to engine operation constantly monitoring rotational speed RPM of crankshaft A ferromagnetic 60 tooth ring gear with two consecutive teeth missing is mounted on flywheel Inductive speed sensor is mounted 1 5 0 25 mm 0 059 0 010 in away from ring gear During rotation an AC voltage pulse is created within sensor for each passing tooth ECU calculates engine speed from time interval between consecutive pulses Two tooth gap creates an interrupted input signal corresponding to specific crankshaft position 84 BTDC for cylinder 1 This signal serves as a reference for control of ignition timing by ECU Synchronization of inductive speed pickup and crankshaft position takes place during first two revolutions each time engine is started Sensor must be properly connected at all times If sensor becomes disconnected for any reason engine will quit running Throttle position sensor TPS is used to indicate throttle plate angle to ECU Since throttle by way of governor reacts to engine load angle of throttle plate is directly related to load on engine Mounted on throttle body intake manifold and operated directly off end of throttle shaft TPS works as a potentiometer var
9. p REFER TO DIAGNOSTIC AID 2 FAULT CODES CLEAR CODES CRANK ENGINE DOES MIL GO OFF KEY OFF AND KEY ON LISTEN FOR FUEL PUMP SPEED SENSOR DOES FUEL PUMP CYCLE ON THEN OFF AFTER 1 2 SECONDS LOCATE ELECTRICAL RELAY WHILE HOLDING RELAY KEY OFF AND KEY ON DOES RELAY CYCLE ON THEN OFF AFTER 1 2 SECONDS Proceed to Start of Test for retest lt H REFER TO DIAGNOSITC AID 5 Yes FUEL PUMP No REFER TO DIAGNOSTIC AID 6 RELAY WHILE CRANKING CHECK IGNITION SYSTEM REFER TO DIAGNOSTIC AID 7 IGNITION SYSTEM Yes WHILE CHECKING CHECK INJECTOR FUEL DELIVERY WET SPARK PLUG Yes INSTALL IN LINE PRESSURE GAUGE AND KEY ON REFER TO DIAGNOSTIC AID 8 FUEL SYSTEM ELECTRICAL FUEL PRESSURE IN SPECIFICATION REFER TO DIAGNOSTIC AID 9 FUEL SYSTEM Yes REFER TO DIAGNOSTIC AID 10 BASE ENGINE 24 690 02 Rev E KohlerEngines com 7T Lubrication System This engine uses a full pressure lubrication system which delivers oil under pressure to crankshaft camshaft connecting rod bearing surfaces and hydraulic valve lifters A high efficiency gerotor oil pump maintains high oil flow and oil pressure even at low speeds and high operating temperatures A pressure relief valve limits maximum pressure of system Oil pan must be removed to service oil pickup pressure relief valve and oil pump Lubrication Components
10. Contamination of air reference Remove source of external contamination protect air reference area upper shield damage Air leak at sensor or gasket sensor Use recommended torque at installation replace gasket or sensor Revise application exhaust Shield sensor from damage High voltage output Silica poisoning Replace sensor Contaminated gasoline Use high quality fuel Engine problem misfire Correct cause of misfire Excessive rich air fuel ratio Check for high fuel pressure Leaking injector Liquid fuel in vent line Wiring shorted to voltage Repair wiring Broken element Sensor dropped Open circuit no activity from sensor system Defective sensor Thermal shock Hard blow to engine or exhaust Replace sensor Slow time response Open heater circuit Improper handling Carbon deposits Replace sensor Improper fueling Correct fueling Incorrect or contaminated fuel Use high quality fuel Excessive engine oil consumption causing exhaust contamination or other exhaust side contamination Correct engine condition specification Heater circuit open shorted or out of Repair short in harness wires replace sensor Manifold Absolute Pressure Sensor MAP A sealed non serviceable assembly A faulty sensor must be replaced If a blink code indicates a problem with manifold absolute pressure sensor
11. NOTE Do not drop starter or strike starter frame Doing so can damage starter Engines in this series use solenoid shift starters Troubleshooting Starting Difficulties Condition Possible Cause Conclusion Starter does not energize Battery Check specific gravity of battery If low recharge or replace battery as necessary Wiring Clean corroded connections and tighten loose connections Replace wires in poor condition and with frayed or broken insulation Starter Switch By pass switch or solenoid with a jumper wire If starter cranks or Solenoid normally replace faulty components Remove and perform individual solenoid test procedure Starter energizes but turns Battery Check specific gravity of battery If low recharge or replace slowly battery as necessary Brushes Check for excessively dirty or worn brushes and commutator Clean using a coarse cloth not emery cloth Replace brushes if excessively or unevenly worn Transmission Or Engine Make sure clutch or transmission is disengaged or placed in neutral This is especially important on equipment with hydrostatic drive Transmission must be exactly in neutral to prevent resistance which could keep engine from starting Check for seized engine components such as bearings connecting rod and piston 24 690 02 Rev E KohlerEngines com 85 Starter System SOLENOID SHIFT ELECTRIC STARTERS Solenoid Shift Starter Components
12. Never attempt to disassemble ECU It is sealed to prevent damage to internal components Warranty is void if case is opened or tampered with in any way All operating and control functions within ECU are preset No internal servicing or readjustment may be performed If a problem is encountered and you determine ECU to be faulty contact your source of supply Do not replace ECU without factory authorization Relationship between ECU and throttle position sensor TPS is very critical to proper system operation If TPS or ECU is changed or mounting position of TPS is altered applicable TPS Initialization Procedure must be performed to restore synchronization Engine speed sensor is a sealed non serviceable assembly If Fault Code diagnosis indicates a problem within this area check and test as follows 1 Check mounting and air gap of sensor It must be 1 5 mm x 0 25 mm 0 059 x 0 010 in 2 Inspect wiring and connections for damage or problems 3 Make sure engine has resistor type spark plugs 52 KohlerEngines com 4 Disconnect main harness connector from ECU 5 Connect an ohmmeter between designated pin terminals in plug 24 Pin MSE 1 0 Plastic Cased ECU 9 and 10 pin terminals 32 Pin MSE 1 1 Plastic Cased ECU 9 and 10 pin terminals See pages 63 and 65 according to ECU style A resistance value of 750 1000 at room temperature 20 C 68 F should be obtained If resistance is corr
13. full oil level 25 TORQUE SPECIFICATIONS ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Blower Housing Into cored aluminum hole or weld nut M5 M6 Into extruded hole in sheet metal M6 6 2 m 55 in Ib into new holes 4 0 m 35 in Ib into used holes 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes 2 8 N m 25 in Ib into new holes 2 3 N m 20 in Ib into used holes 2 8N 2 3 N 3j 33 25 in Ib into new holes 20 in Ib into used holes 6 2 m 55 in Ib into new holes 4 0 m 35 in Ib into used holes 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes Connecting Rod Cap Fastener torque in increments 8 mm straight shank 8 mm step down 6 mm straight shank 11 6 N m 103 in Ib 200 in Ib 130 in Ib 22 7 Nm 14 7 N m 11 3 N m 100 in Ib Crankcase Breather Cover Fastener 11 3 N m 100 in Ib into new holes 7 3 N m 65 in Ib into used holes 7 3 N m 65 in Ib Values are in Metric units Values in parentheses are English equivalents Exceeding maximum angle of operation may cause engine damage from insufficient lubrication 5 Lubricate threads with engine oil prior to assembly Any and all horsepower hp references by Kohler are Certified Power Ratings and per SAE J1940 amp J1995 hp standards Details on Certified Power Ratings c
14. E WARNING 4 4 Do not fill fuel tank while engine is hot or running Wy Explosive Fuel can cause fires and severe burns Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved containers in well ventilated unoccupied buildings away from sparks or flames Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition Never use gasoline as a cleaning agent Typical electronic fuel injection EFI system and related components include Fuel pump module and lift pump Fuel filter High pressure fuel line Fuel line s Fuel injectors Throttle body intake manifold Electronic control unit ECU Ignition coils Engine oil temperature sensor Throttle position sensor TPS Crankshaft position sensor Oxygen sensor Manifold absolute pressure sensor MAP Wire harness assembly amp affiliated wiring Malfunction indicator light MIL optional Intake air temperature sensor FUEL RECOMMENDATIONS Refer to Maintenance FUEL LINE Low permeation fuel line must be installed on all Kohler Co engines to maintain EPA and CARB regulatory compliance OPERATION NOTE When performing voltage or continuity tests avoid putting excessive pressure on or against connector pins Flat pin probes are recommended for testing to avoid spreading or bending terminals EFI system is designed to provide peak engine perf
15. E EFI SYSTEM BOSCH 32 Pin MSE 1 1 Plastic Cased ECU Pin circuit 29 e ECU Diagnostic Aid 4 SPEED SENSOR MIL does not turn off during cranking Indicates ECU is not receiving a signal from speed sensor Possible causes e Speed sensor e Speed sensor circuit problem 24 Pin MSE 1 0 Plastic Cased ECU Pin circuits 9 and 10 32 Pin MSE 1 1 Plastic Cased ECU Pin circuits 9 and 10 e Speed sensor toothed wheel air gap e Toothed wheel e Flywheel key sheared e ECU Diagnostic Aid 5 FUEL PUMP fuel pump not turning on Possible causes e Fuel pump fuse e Fuel pump circuit problem 24 Pin MSE 1 0 Plastic Cased ECU Circuits 30 87 and relay 32 Pin MSE 1 1 Plastic Cased ECU Circuits 30 87 and relay e Fuel pump Diagnostic Aid 6 RELAY relay not operating Possible causes e Safety switches circuit s problem 24 Pin MSE 1 0 Plastic Cased ECU Circuit 3 32 Pin MSE 1 1 Plastic Cased ECU Circuit 25 Relay circuit s problem 24 Pin MSE 1 0 Plastic Cased ECU Circuits 18 85 30 and 87 32 Pin MSE 1 1 Plastic Cased ECU Circuits 28 85 30 and 87 e Relay e ECU grounds ECU Diagnostic Aid 7 IGNITION SYSTEM no spark Possible causes e Spark plug e Plug wire e Coil e Coil circuit s 24 Pin MSE 1 0 Plastic Cased ECU Circuits 22 23 65 66 30 and relay 32 Pin MSE 1 1 Plastic Cased ECU Circuits 30 31 65 66 relay and relay c
16. ECU is reset A TPS Learn Procedure must be performed after ECU Reset 28 KohlerEngines com TPS Learn Procedure 1 Turn idle screw clockwise one full turn prior to key ON after ECU Reset 2 Start engine run at low idle until engine is warm 3 Idle speed must be above 1500 RPM If below 1500 RPM turn idle screw up to 1700 RPM and then shut down engine and perform ECU Reset again 4 Adjust idle speed down to 1500 RPM Allow engine to dwell at 1500 RPM for about 3 seconds 5 After this adjust idle speed to final specified speed setting 6 Turn key OFF and count to 10 seconds Learn procedure is complete 24 690 02 Rev E EFI SYSTEM ECV JO O UUOD onsouBeiq fv Josuegs eJnje1eduus JOSU9S Josues eJnssaJgd JOSU9S diy exexul IV aumgsdugi yo HY onge poust 9V uojsogemouj dV Josuesusbixo av JOSU9S uonisog weysyuerg QV Z OD uous ov L lO uoniuf av Z 10 99fu jen vy L Joyoalu on z JOD UUO3 a19 A JOjD9UU09 M9e g X osn VOL M TW A UDJIMS 9JnsS9Jg lO n JOJO JOWeIS L 10 p9uu09 jeulwdea 9 S duung jan A apeg o esnJj voe d JojejnDes 1eynoes o JOJeS N xoelg W a5 1 SJIUM M uel f Mud I ejdung H ang eq 9 usa19 eq E usa19 jur 3 MOJISA a eyuMWpes xoe g pesl a peu Vv H i 69 ay m TIE G 9 ea t 9 LEES zi lt Hi ES L uobosooob 6 out
17. damaged Engine Wiring Harness Related 24 Pin MSE 1 0 Plastic Cased ECU e Pin circuits 4 8 and or 14 damaged wiring connectors e Pin circuits 4 8 and or 14 routed near noisy electrical signal coils alternator e Intermittent 5 volt source from ECU pin circuit 14 Engine Wiring Harness Related 32 Pin MSE 1 1 Plastic Cased ECU e Pin circuits 4 8 and or 18 damaged wiring connectors e Pin circuits 4 8 and or 18 routed near noisy electrical signal coils alternator e Intermittent 5 volt source from ECU pin circuit 18 ECU Harness Related e ECU to harness connection problem Code 23 Component ECU Fault ECU is unable to recognize or process signals from its memory Condition Engine will not run Conclusion ECU internal memory problem e Diagnosable only through elimination of all other system component faults Code 24 Will not blink out Code 22 Component Throttle Position Sensor TPS Fault Unrecognizable signal is being sent from sensor too high too low inconsistent Component Engine Speed Sensor Fault No tooth signal from speed sensor MIL light will not go out when cranking Condition None engine will not start or run as ECU is unable to estimate speed Condition A limp home operating mode occurs with an overall decrease in operating performance and effici
18. fresh sealant Using outdated sealant can result in leakage 1 106 Be sure sealing surfaces have been cleaned and prepared as described at beginning of Disassembly Inspection and Service Check to make sure that there are no nicks or burrs on sealing surfaces of oil pan or crankcase Use a new gasket or apply RTV a For an oil pan with a gasket 1 Before installing gasket check to make sure O ring is present in counter bore around dowel pin b For an oil pan with RTV 1 Apply a 1 5 mm 1 16 in bead of sealant to sealing surface of oil pan Verify O ring is present Make sure end of governor cross shaft is lying against bottom of cylinder 1 inside crankcase Install oil pan to crankcase Carefully seat camshaft and crankshaft into their mating bearings Rotate crankshaft slightly to help engage oil pump and governor gear meshes KohlerEngines com 6 Install screws securing oil pan to crankcase Torque fasteners in sequence shown to 25 6 N m 227 in Ib One mounting screw has a thread sealant patch This screw is typically installed in number 10 hole shown Reapply pipe sealant with Teflon Loctite 592 PST Thread Sealant or equivalent to number 10 oil pan screw as required Oil Pan Fastener Torque Sequence Install Stator and Backing Plate 1 Apply pipe sealant with Teflon Loctite 592 PST Thread Sealant or equivalent to stator mounting holes Position
19. from base holder Internal In Tank Regulator Remove screws securing retaining ring and regulator in base holder assembly Grasp and pull regulator out of base holder 5 Always use new O Rings and hose clamps when installing a regulator A new replacement regulator will have new O Rings already installed Lubricate O Rings external regulator with light grease or oil 6 Install new regulator by carefully pushing and rotating it slightly into base or housing a External Regulators with Square Base Housing Only Install a new O Ring between regulator and mounting bracket Set mounting bracket into position b Secure regulator in base with original retaining ring or screws Be careful not to dent or damage body of regulator as operating performance can be affected 7 Reassemble and connect any parts removed in step 3 8 Reconnect negative battery cable 9 Recheck regulated system pressure at fuel rail test valve Fuel Rail Fuel rail is mounted to throttle body intake manifold No specific servicing is required unless operating conditions indicate that it needs internal cleaning or replacement It can be detached by removing mounting screws and injector retaining clips Thoroughly clean area around all joints and relieve any pressure before starting any disassembly Depending on application regulator may be located in fuel tank along with fuel pump or outside tank just
20. it can be tested as follows 1 Make sure all connections are making proper contact and are free of dirt and debris Remove blower housing Slide locking tab out and pull off manifold absolute pressure connector Turn key Switch to ON and check with a volt meter by contacting red lead to pin 1 and black lead to pin 2 There should be 5 volts present indicating ECU and wiring harness are functioning 3 2 Check continuity in wire harness Ohms between Pin 3 at sensor connector and Black pin 11 connector at 34 KohlerEngines com ECU should be near zero ohms If no continuity is measured or very high resistance replace wire harness Check to make sure intake manifold is not loose and MAP sensor is not loose Loose parts would allow a vacuum leak making MAP sensor report misleading information to ECU a Tighten all hardware and perform an ECU Reset and a TPS Learn Procedure to see if MIL will display a fault with MAP sensor again If MIL finds a fault with MAP sensor replace it 24 690 02 Rev E A WARNING Explosive Fuel can cause fires and severe burns Fuel Injectors Fuel system ALWAYS remains under HIGH PRESSURE Wrap a shop towel completely around fuel pump module connector Press release button s and slowly pull connector away from fuel pump module allowing shop towel to absorb any residual fuel in high pressure fuel line Any spilled fuel must be completely wiped up immediately Details
21. 1 1563 1 1665 in F Valve Face Angle 45 45 G Valve Margin Min 1 5 mm 0 0591 in 1 5 mm 0 0591 in H Valve Stem Diameter 6 982 7 000 mm 0 2749 0 2756 in 6 970 6 988 mm 0 2744 0 2751 in After cleaning check flatness of cylinder head and Hard starting or loss of power accompanied by high corresponding top surface of crankcase using a surface fuel consumption may be symptoms of faulty valves plate or piece of glass and feeler gauge as shown Although these symptoms could also be attributed to Maximum allowable out of flatness is 0 076 mm 0 003 worn rings remove and check valves first After removal in clean valve heads faces and stems with a power wire brush Then carefully inspect each valve for defects such as a warped head excessive corrosion or a worn stem end Replace valves found to be in bad condition Carefully inspect valve mechanism parts Inspect valve springs and related hardware for excessive wear or distortion Check valves and valve seat area or inserts for evidence of deep pitting cracks or distortion Check clearance of valve stems in guides See valve details and specifications 96 KohlerEngines com 24 690 02 Rev E Valve Guides If a valve guide is worn beyond specifications it will not guide valve in a straight line This may result in burnt valve faces or seats loss of compression and excessive oil consumption To check valve guide to valve stem clearance thoroughly clean valv
22. 5 6 minutes more between idle and midrange 2 Adjust idle speed screw located on throttle body as necessary Standard idle speed setting for EFI engines is 1500 RPM but certain applications might require a different setting 3 Adjust high speed stop as necessary located on control panel if equipped Make sure maximum engine speed does not exceed 4200 RPM no load 118 KohlerEngines com 24 690 02 Rev E 24 690 02 Rev E KohlerEngines com 119 1P24 690 02 2012 by Kohler Co All rights reserved 6 50531 9654 120 KohlerEngines com 24 690 02 Rev E 4
23. 9 300 40 7 360 17 0 150 Tightening Torque N m ft Ib 10 M10 21 7 16 27 1 20 47 5 35 66 4 49 81 4 60 33 9 25 M12 36 6 27 47 5 35 82 7 61 116 6 86 139 7 103 61 0 45 M14 58 3 43 76 4 56 131 5 97 184 4 136 219 7 162 94 9 70 Torque Conversions N m in Ib x 0 113 in lb N m x 8 85 N m ft Ib x 1 356 ft Ib N m x 0 737 14 KohlerEngines com 24 690 02 Rev E Tools and Aids Certain quality tools are designed to help you perform specific disassembly repair and reassembly procedures By using these tools you can properly service engines easier faster and safer In addition you ll increase your service capabilities and customer satisfaction by decreasing engine downtime Here is a list of tools and their source SEPARATE TOOL SUPPLIERS Kohler Tools SE Tools Design Technology Inc Contact your local Kohler source of 415 Howard St 768 Burr Oak Drive supply Lapeer MI 48446 Westmont IL 60559 Phone 810 664 2981 Phone 630 920 1300 Toll Free 800 664 2981 Fax 630 920 0011 Fax 810 664 8181 TOOLS Description Source Part No Alcohol Content Tester Kohler 25 455 11 S For testing alcohol content 96 in reformulated oxygenated fuels Camshaft Endplay Plate SE Tools KLR 82405 For checking camshaft endplay Camshaft Seal Protector Aegis SE Tools KLR 82417 For protecting seal during camshaft installation Cylinder Leakdown Tester Kohler 25 761 05 8 For checking combustion re
24. Electronic Control Unit ECU EFI SYSTEM ECV Grey Connector Pinout of ECU Black Connector Pin 2 Description 1 Not Used 2 Not Used 3 Malfunction Indicator Light MIL Ground 4 Not Used 5 Not Used 6 Not Used 7 Not Used 8 Not Used 9 Battery Ground 10 Ignition Coil 2 Ground 11 Not Used 12 Not Used 13 Not Used 14 Safety Switch Ground 15 Not Used 16 ECU 17 Fuel Pump Control 12V 18 Not Used Pin Function 1 lgnition Coil 1 Ground 2 Battery Ground 3 Diagnostic Communication Line 4 Speed Sensor input 5 Fuel Injector Output 1 Ground 6 Fuel Injector Output 2 Ground 7 Oxygen Sensor Heater 8 Intake Air Temperature IAT sensor input 9 Fuel Pump Ground 10 Ground for IAT TPS MAP O2 and Oil Sensors 11 Manifold Absolute Pressure MAP sensor input 12 Throttle Position Sensor TPS input 13 Speed Sensor Ground 14 Oil Temperature Sensor input 15 Ignition Switch Switched 12V 16 Power for TPS and MAP Sensors 5V 17 Oxygen Sensor O2 input 18 Battery Power Permanent 12V 24 690 02 Rev E BLACK 123456789 E w m m m w w um 10 11 12 13 14 15 16 17 18 m m m w w u u 10 11 12 13 14 15 16 17 18 Pinou
25. M8 X 1 25 N 1 969 4 STUDS E EXHAUST FILL amp PORT 2 STICK e 5 1 e 0 00 E S S 3 1 969 EXHAUST PORT 1 104 02 4095 24187 f m 9 523 SX SOLENOID OQ JE i SHIFT STARTER MOUNTING HOLE A 4X 9 20 362 THRU 254 00 10 000 B C ENGINE MOUNTING SURFACE PTO SIDE 2 ENGINE MOUNTING SURFACE OIL FILL amp DIPSTICK SERIA 367 37 14 463 317 23 12 489 ENGINE 1349 CU Om S z OIL DRAIN PLUG 4041 STARTER 3 8 N P T INCH 1 591 SIDE 24 690 02 Rev E KohlerEngines com ENGINE IDENTIFICATION NUMBERS Specifications Kohler engine identification numbers model specification and serial should be referenced for efficient repair ordering correct parts and engine replacement Model eet deeds cid Len ECV630 EFI Command Engine Vertical Shaft Numerical Designation Specification ECV630 3001 Serial cou novi Bada uS 9923500328 Year Manufactured Code T Factory Code Code Year 39 2009 40 2010 41 2011 GENERAL SPECIFICATIONS 5 ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Bore 80 mm 3 15 in 83 mm 3 27 in 83 mm 3 27 in Stroke Displacement 69 mm 694 cc 42 4 cu in 2 72 in 747 cc 45 6 cu in 67 mm 2 64 in 725 cc 44 cu in Oil Capacity refill 1 9 L 2 0 U S qt Maximum Angle of Operation
26. NOTE If crankpin is reground visually check to ensure fillet blends smoothly with crankpin surface Inspect gear teeth of crankshaft If teeth are badly worn chipped or some are missing replacement of crankshaft will be necessary Inspect crankshaft bearing surfaces for scoring grooving etc Some engines have bearing inserts in crankshaft bore of oil pan and or crankcase Do not replace bearings unless they show signs of damage or are out of running clearance specifications If crankshaft turns easily and noiselessly and there is no evidence of scoring grooving etc on races or bearing surfaces bearings can be reused Inspect crankshaft keyways If they are worn or chipped replacement of crankshaft will be necessary 102 KohlerEngines com H This Fillet Area Must Be Completely Smooth Inspect crankpin for score marks or metallic pickup Slight score marks can be cleaned with crocus cloth soaked in oil If wear limits as stated in Specifications and Tolerances are exceeded it will be necessary to either replace crankshaft or regrind crankpin to 0 25 mm 0 010 in undersize If reground a 0 25 mm 0 010 in undersize connecting rod big end must then be used to achieve proper running clearance Measure crankpin for size taper and out of round Connecting rod journal can be ground one size under When grinding a crankshaft grinding stone deposits can get caught in oil passages which could cause severe engine dam
27. O OO O O O OjOy8I gell 410 99UU09 JeuUIWE 9 We1Berg BUM LI ssousey BuuiM 29 KohlerEngines com 24 690 02 Rev E JO O UUOD onsouBeiq fv LLI JOSUSS eJnje1eduus Josuesg Josues eJnssaJgd JOSU9S diy exejul Iv enjeJeduje WO HV e amp njsqvpiojuew OV uonisog y L dV Josueg usB XO AV Josuag uonisog yeusxyuel av ZK 1103 uoniuB ov L 1100 uoniu av ZH 10 2efu jen vy L Jojosluj jen z 9 JOj98UU09 a19 A JOjD9UU09 yoe g X esnJ voL M TW A UJJIMS a1NSSAIJ IO n a JOJO JO UPS L Joyoouuog jeuuus 9 S duung jan A apeg o esnJj voe d Joyeinbay seynooy o JojejS N yoelg W Kai 7 SUM y uel f MUld I ajding H eng eq 9 used eq 4 u 19 1UBII 3 MO ISA a EME 9 xoelg pes a poy V Elte 6 99 A ul LO peu Hm mm A E R S 8 E 653 6 S D S E Coo D 2 O O In TY o E o O o O o O o O o O O O EFI SYSTEM ECV j euondo YyoyIMg Aay Joja9uu09 jeuruue c we1Beg BuniM LIZ S Crankshaft Position Sensor A sealed non serviceable assembly If Fault Code diagnosis indicates a problem within this area test and correct as follows 1 Check mounting and air gap of sensor It must be 0 20 0 70 mm 0 008 0 027 in 2 Inspect wiring and connections for damage or problems 3 Make sure engine has resistor type spark plugs Disco
28. PLUG NO REFER TO DIAGNOSTIC AID 7 FUEL SYSTEM ELECTRICAL YES INSTALL IN LINE PRESSURE GAUGE AND KEY ON UEL PRESSUR IN SPECIFICATION PUMP REFER TO DIAGNOSTIC AID 8 NO FUEL SYSTEM YES REFER TO DIAGNOSTIC AID 9 BASIC ENGINE 1 After turning key to OFF wait 10 seconds before turning to ON to allow ECU to go to sleep 2 Fuel pump module can be heard or a vibration can be felt to establish pump cycle Fuel pump module will run for one 4 6 second cycle when ECU wakes up after being asleep 24 690 02 Rev E KohlerEngines com 47 EFI SYSTEM BOSCH A WARNING Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved Explosive Fuel can cause fires and severe containers in well ventilated unoccupied buildings away burns from sparks or flames Spilled fuel could ignite if it comes 4 4 Do not fill fuel tank while engine is hot or in contact with hot parts or sparks from ignition Never use running gasoline as a cleaning agent Bosch EFI System ay T m 4 G LA A Fee 8 Cu M Fuel Pressure A Regulator B Valley Baffle C Air Deflector D Fuel Rail g Throttle Position E Intake Manifold Kit F Sensor G Module H Fuel Injector l ECU J Speed Pick up Sensor K do SEH L Screw M Intake Gasket N Fuel Filter Fuel Pump Assembly 48 KohlerEngines com 24 690 02 Rev E Typica
29. Starter Motor 1 Disconnect leads from starter 2 Remove screws Remove Oil Separator and Hardware Remove screws securing oil separator assembly pulling assembly out and away from valve cover Remove Debris Screen NOTE Fan will be loose but cannot be removed until after blower housing is removed 1 Remove socket head cap screws securing metal screen and remove screen 2 Remove spacers paying attention to curvature of spring washers between spacers and fan 3 Ifthere is a plastic debris screen attached to fan remove screws securing debris screen Removing screen will expose screws fastening fan to flywheel 24 690 02 Rev E Disassembly Inspection and Service Remove Outer Baffles and Blower Housing NOTE Some engines may have 2 fuses mounted to a bracket above ECU and a third in line fuse by rectifier regulator 1 Disconnect plug from rectifier regulator 2 Remove silver plated rectifier regulator ground strap screw fastened to crankcase Rectifier regulator does not have to be detached from blower housing 3 Disconnect 3 fuse connectors on outer baffle and allow them to hang 4 Remove screws securing outer baffles Note location of any lifting strap and position of short screws for reassembly Coil and any hoses may remain attached to baffle after being unplugged or disconnected 5 Remove outer baffles 6 Remove remaining screws securing blower housing Remove blower housing
30. WARNING Carbon Monoxide can cause severe nausea fainting or death Avoid inhaling exhaust fumes WARNING Rotating Parts can cause severe injury Stay away while engine is in operation Engine exhaust gases contain poisonous carbon monoxide Carbon monoxide is odorless colorless and can cause death if inhaled Keep hands feet hair and clothing away from all moving parts to prevent injury Never operate engine with covers shrouds or guards removed A partial vacuum should be present in crankcase when engine is operating Pressure in crankcase normally caused by a clogged or improperly assembled breather can cause oil to be forced out at oil seals gaskets or other available spots Crankcase vacuum is best measured with either a water manometer or a vacuum gauge Complete instructions are provided in kits To test crankcase vacuum with manometer 1 Insert rubber stopper into oil fill hole Be sure pinch clamp is installed on hose and use tapered adapters to connect hose between stopper and one manometer tube Leave other tube open to atmosphere Check that water level in manometer is at 0 line Make sure pinch clamp is closed 2 Start engine and run no load high speed 3 Open clamp and note water level in tube Level in engine side should be a minimum of 10 2 cm 4 in above level in open side If level in engine side is less than specified low no vacuum or level in engin
31. aegis Engine Wiring Harness Related harai tout tem Too High e Pin circuit wiring or connectors Charging Output System Too Hig ECU pin Black 4 or Black 13 e ECU to harness connection problem If code is stored in fault history and starts normally Clear code no other service required 44 KohlerEngines com 24 690 02 Rev E Code 0351 Component Ignition Coil Fault Cylinder 1 Ignition Coil Malfunction Condition Broken wire in harness may not be visible shorted connection or faulty sensor Conclusion Engine Wiring Harness Related e Connection to ignition or fuse e Pin circuit wiring or connectors e ECU pin Black 1 e ECU to harness connection problem Ignition System Related e Incorrect spark plug s used e Poor connection to spark plug Code 0352 Component Ignition Coil Fault Cylinder 2 Ignition Coil Malfunction Condition Broken wire in harness may not be visible shorted connection or faulty sensor Conclusion Engine Wiring Harness Related e Connection to ignition or fuse e Pin circuit wiring or connectors ECU pin Grey 10 e ECU to harness connection problem Ignition System Related e Incorrect spark plug s used e Poor connection to spark plug Code 0562 Component System Voltage Fault System Voltage Low Condition Faulty voltage regulator bad fuse or shorted connection Conclusion Corroded Connections Bad Stator Bad Batt
32. any joint or fitting with parts cleaning solvent before opening to prevent dirt from entering system Always depressurize fuel system through fuel connector on fuel pump module before disconnecting or servicing any fuel system components Never attempt to service any fuel system component while engine is running or ignition switch is ON Do not use compressed air if system is open Cover any parts removed and wrap any open joints with plastic if they will remain open for any length of time New parts should be removed from their protective packaging just prior to installation Avoid direct water or spray contact with system components Do not disconnect or reconnect ECU wiring harness connector or any individual components with ignition on This can send a damaging voltage spike through ECU Do not allow battery cables to touch opposing terminals When connecting battery cables attach positive cable to positive battery terminal first followed by negative cable to negative battery terminal Never start engine when cables are loose or poorly connected to battery terminals Never disconnect battery while engine is running Never use a quick battery charger to start engine Do not charge battery with key switch ON Always disconnect negative battery cable before charging battery and also unplug harness from ECU before performing any welding on equipment 26 KohlerEngines com 24 690 02 Rev E ELECTRICAL COMPONENTS
33. be connected to outlet barb of lift fuel pump and secured with a spring clamp NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connector has seal in place NOTE Fuel pump module pins should be coated with a thin layer of electrical grease to prevent fretting and corrosion and may be reapplied if fuel pump module is being reused 1 Install lift fuel pump and lines as an assembly Connect pulse line to crankcase vacuum fitting Install lift fuel pump to bracket on housing using screws Torque M6 screws to 7 3 N m 68 in Ib in new holes or 6 2 N m 55 in Ib in used holes Connect in line 10 micron EFI fuel filter and hose to inlet barb of lift fuel pump and secure with spring clamp Install fuel pump module baffle to crankcase using screws Torque screws to 11 9 N m 105 in Ib Push high pressure fuel line connector onto fuel pump module fitting If Oetiker clamp was cut to remove inlet fuel line slide a new Oetiker clamp onto fuel line and connect fuel line Only use an Oetiker clamp pliers to crimp Oetiker clamps Oetiker clamp crimp must point up away from top of fuel pump module and abrasion sleeve must be positioned over Oetiker clamp 7 Connect electrical connector to top of fuel pump module Ensure grey locking tab is pulled out before connecting Push connector onto terminal until a click is heard then push in grey locking tab to lock connector 8 Install fuel pump module to baffle u
34. by excess fuel or oil in combustion chamber Excess fuel could be caused by a restricted air cleaner a carburetor problem or operating engine with too much choke Oil in combustion chamber is usually caused by a restricted air cleaner a breather problem worn piston rings or valve guides KohlerEngines com 24 690 02 Rev E Carbon Fouled Soft sooty black deposits indicate incomplete combustion caused by a restricted air cleaner over rich carburetion weak ignition or poor compression Overheated Chalky white deposits indicate very high combustion temperatures This condition is usually accompanied by excessive gap erosion Lean carburetor settings an intake air leak or incorrect spark timing are normal causes for high combustion temperatures Electrical System BATTERY A 12 volt battery with 400 cold cranking amps cca is generally recommended for starting in all conditions A smaller capacity battery is often sufficient if an application is started only in warmer temperatures Refer to following table for minimum capacities based on anticipated ambient temperatures Actual cold cranking requirement depends on engine size application and starting temperatures Cranking requirements increase as temperatures decrease and battery capacity shrinks Refer to equipment s operating instructions for specific battery requirements Battery Size Recommendations Temperature Batter
35. codes what they correspond to and what visual indications will be Following chart is a list of individual codes with an explanation of what triggers them what symptoms might be expected and probable causes 24 Pin 32 Pin OBD2 Blink P Code Connection or Failure MEO DEL Note Code Applicable to 32 Description Cased Cased Pin MSE 1 1 ECU ECU ECU System Only System System No RPM Signal Y 21 P0335 Loss of Synchronization Y 22 P0120 TPS Signal Implausible N 2 22 P0122 TPS Open or Short Circuit to Ground Y 22 P0123 TPS Short Circuit to Battery Y 23 P0601 Defective ECU Y 24 Engine Speed Sensor Y 9 31 P0174 System too Lean Y 6 31 P0132 O Sensor Circuit Shorted to Battery N 3 O Sensor Circuit No Activity De 32 P0134 tested N 8 33 P0175 System too Rich Y 78 33 P0020 O Sensor Control at Upper Limit Y 34 P0171 Maximum Adaption Limit Reached Y 8 34 P0172 Minimum Adaption Limit Reached Y 8 Temperature Sensor Circuit Shorted 42 P0117 to Ground Y 68 KohlerEngines com 24 690 02 Rev E EFI SYSTEM BOSCH Blink P Code Connection or Fail MSE to MSE T Bode wee r Comgeten or Faure Co E NS ECU System Only Sen SE 42 porte oe Y Y 43 N A Offset below minimum allowable limit N A Y Failure Completing Autolearn TPS 44 N A ia above maximum allowable N A Y 51 P1260 Injector 1 Open
36. continuity tester across blade terminal and metal case of switch With O psi pressure applied to Switch tester should indicate continuity switch closed 2 Gradually increase pressure to switch As pressure increases through range of 2 0 5 0 psi tester should indicate a change to no continuity switch open Switch should remain open as pressure is increased to 90 psi maximum 3 Gradually decrease pressure through range of 2 0 5 0 psi Tester should indicate a change to continuity switch closed down to 0 psi 4 Replace switch if it does not operate as specified Normally Open Switch 1 Connect continuity tester across blade terminal and metal case of switch With O psi pressure applied to Switch tester should indicate no continuity switch open 2 Gradually increase pressure to switch As pressure increases through range of 2 0 5 0 psi tester should indicate a change to continuity switch closed Switch should remain closed as pressure is increased to 90 psi maximum 3 Gradually decrease pressure through range of 2 0 5 0 psi Tester should indicate a change to no continuity switch open down to 0 psi CV Models Pressure Switch PSI 12 099 04 2 6 24 099 03 2 5 25 099 27 2 5 28 099 01 2 6 48 099 07 12 16 52 099 08 7 11 52 099 09 7 11 KohlerEngines com 79 Electrical System SPARK PLUGS Inspection A CAUTION W Electrical Shock can cause injury Do not
37. each time engine is started Sensor must be properly connected at all times If sensor becomes disconnected for any reason engine will quit running Throttle position sensor TPS is used to indicate throttle plate angle to ECU Since throttle by way of governor reacts to engine load angle of throttle plate is directly related to load on engine Mounted on throttle body and operated directly off end of throttle shaft TPS works as a potentiometer varying voltage signal to ECU in direct correlation to angle of throttle plate This signal along with other sensor signals is processed by ECU and compared to internal preprogrammed maps to determine required fuel and ignition settings for amount of load Correct position of TPS is established and set at factory Do not loosen TPS or alter mounting position unless absolutely required by fault code diagnosis If TPS is loosened or repositioned appropriate TPS Learn Procedure must be performed to re establish baseline relationship between ECU and TPS Engine oil temperature sensor is used by system to help determine fuel requirements for starting a cold engine needs more fuel than one at or near operating temperature Mounted in breather cover it has a temperature sensitive resistor that extends into oil flow Resistance changes with oil temperature altering voltage sent to ECU Using a table stored in its memory ECU correlates voltage drop to a specific temperature Using fu
38. hole with threaded hole in ECU bracket Secure with M5 screw Torque screw to 6 2 N m 55 in Ib into new holes or 4 0 N m 35 in Ib into used holes KohlerEngines com 113 Reassembly ECU ECV EFI Install Electronic Control Unit ECU a A Electronic Control B ECU Bracket Unit ECU C Starter NOTE ECU pins should be coated with a thin layer of electrical grease to prevent fretting and corrosion and may need to be reapplied if ECU is being reused 1 Install ECU to ECU bracket using screws Torque M5 screws to 6 2 N m 55 in Ib into new holes or 4 0 N m 35 in Ib into used holes 2 Connect Black and Grey electrical connectors Connectors and ECU are keyed in such a way so they cannot be installed incorrectly Install Throttle Body NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connector has seal in place 1 Install a new throttle body O ring prior to installation Make sure all holes align and are open 2 Install throttle body throttle position sensor intake air temperature sensor throttle linkage spring and bushing as an assembly 3 Install air cleaner bracket models with heavy duty air cleaner only to throttle body with screws Torque screws to 9 9 N m 88 in Ib 4 Connect breather separator hose to top of throttle body using a pliers to compress spring clip Route hose through housing by pressing hose into cutout
39. housing Apply drive lubricant to armature shaft splines Install drive pinion onto armature shaft Install and assemble stop collar retainer assembly a Install stop collar down onto armature shaft with counter bore recess up b Install a new retainer in larger rear groove of armature shaft Squeeze with a pliers to compress it in groove c Slide stop collar up and lock it into place so recess surrounds retainer in groove If necessary rotate pinion outward on armature splines against retainer to help seat collar around retainer Install offset thrust stop washer so smaller offset of washer faces retainer collar Apply a small amount of oil to bearing in drive end cap and install armature with drive pinion Lubricate fork end and center pivot of drive lever with drive lubricant Position fork end into space between captured washer and rear of pinion Slide armature into drive end cap and at same time seat drive lever into housing Install rubber grommet into matching recess of drive end cap Molded recesses in grommet should be out matching and aligned with those in end cap Install frame with small notch forward onto armature and drive end cap Align notch with corresponding section in rubber grommet Install drain tube in rear cutout if it was removed previously Install flat thrust washer onto commutator end of armature shaft Starter reassembly when replacing brushes brush holder assembly a
40. of blower housing Position abrasion sleeve 5 Push electrical connector onto intake air temperature sensor making sure a good connection is made by listening for a click 6 Connect 5 32 in LD vent hose from fuel pump module to bottom of throttle body 7 Push electrical connector onto throttle position sensor making sure a good connection is made 114 KohlerEngines com 24 690 02 Rev E Reassembly WARNING y burns A running Explosive Fuel can cause fires and severe Do not fill fuel tank while engine is hot or Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved containers in well ventilated unoccupied buildings away from sparks or flames Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition Never use gasoline as a cleaning agent Fuel Pump ECV EFI Install Lift Fuel Pump and Fuel Pump Module Outlet to Fuel Pump A Pulse Pump Inlet Hose Module Pulse Hose E Electrical Connector Fuel Pump Module Fuel as ee l Oetiker Clamp 24 690 02 Rev E KohlerEngines com 115 Reassembly NOTE Some applications may have two in line fuel filters In those applications connect in line 51 75 micron mesh fuel filter and hose to inlet barb of lift fuel pump and secure with a spring clamp In line 10 micron EFI paper fuel filter and hose must
41. on in third seguence Time between seguences must be less than 2 5 seconds 3 Any stored fault codes will then be displayed as a series of MIL blinks from 2 to 6 representing first digit followed by a pause and another series of blinks from 1 to 6 for second digit a It s a good idea to write down codes as they appear as they may not be in numerical sequence b Code 61 will always be last code displayed indicating end of code transmission If code 61 appears immediately no other fault codes are present Example of Diagnostic Display 2 Long Pause 1 Diagnostic display initiated through ignition key sequencing 3 gt Long Pause A Ur e ee 5 39 4 e 2 Code 61 Code 32 E 6 7 ted Light remains on at end of transmission 24 690 02 Rev E KohlerEngines com 67 EFI SYSTEM BOSCH After problem has been corrected fault codes may be cleared as follows 1 Disconnect negative battery cable from battery terminal or remove main fuse for ECU for approximately 1 minute 2 Reconnect cable and tighten securely or reinstall main fuse Start engine and allow it to run for several minutes MIL should remain off if problem was corrected and fault codes should not reappear codes 31 32 33 and 34 may require 10 15 minutes of running to reappear Following chart lists fault
42. problem with key Switch in wiring or at connector b If voltage is present wiring to connector is good Turn ignition switch OFF and proceed to Step 5 to test relay Connect an ohmmeter Rx1 scale between 85 and 86 terminals in relay There should be continuity 6 Attach ohmmeter leads to 30 and 87 terminals in relay First there should be no continuity Using a 12 volt power supply connect positive lead to 85 terminal and touch negative lead to 86 terminal When 12 volts is applied relay should activate and continuity should exist between 30 and 87 terminals Repeat test several times If at any time t relay fails to activate tcircuit replace relay Fuel Injector Details A Filter Strainer In B Electrical Fuel Supply Connection Solenoid Winding D Valve Housing E Armature F Valve Body Multi Orifice Director G Valve Needle H Plate With Calibrated Opening Injector problems typically fall into three general categories electrical dirty clogged or leakage An electrical problem usually causes one or both of injectors to stop functioning Several methods may be used to check if injectors are operating KohlerEngines com 24 690 02 Rev E 1 With engine running at idle feel for operational vibration indicating that they are opening and closing 2 When temperatures prohibit touching listen for a buzzing or
43. set to Rx1 scale Touch probes between 2 different segments of commutator and check for continuity Test all segments Continuity must exist between all or armature is bad Check for continuity between armature coil segments and commutator segments There should be no continuity If continuity exists between any 2 armature is bad Check armature windings insulation for shorting ft Fork Check that shift fork is complete and pivot and contact areas are not excessively worn cracked or broken Brush Replacement 4 brushes and springs are serviced as a set Use a new Kohler brush and spring kit if replacement is necessary 1 2 24 690 02 Rev E Perform steps 1 5 in Starter Disassembly Remove screws securing brush holder assembly to end cap plate Note orientation for reassembly later Discard old brush holder assembly Clean component parts as required New brushes and springs come preassembled in a brush holder with a protective sleeve that will also serve as an installation tool Perform steps 10 13 in Starter Reassembly sequence If starter has been disassembled installation must be done after armature drive lever and frame are installed Starter System Starter Reassembly NOTE Always use a new retainer Do not reuse old retainers that have been removed NOTE Correctly installed center pivot section of drive 10 KohlerEngines com lever will be flush or below machined surface of
44. throttle lever and manifold boss to firmly hold throttle against idle stop On some EFI engines there is a dampening spring on end of idle speed screw Dampening spring if used should be fully compressed and tab on throttle lever in direct contact with speed screw Adjust idle speed to 1500 RPM using a tachometer 6 Shut off engine 7 Locate service connector plug in wiring harness KohlerEngines com 53 EFI SYSTEM BOSCH 10 11 24 Pin MSE 1 0 Plastic Cased ECU Connect a jumper wire from TPS initialization pin 24 violet wire to battery voltage pin red wire or use jumper plug with blue jumper wire Hold throttle against idle speed stop screw turn ignition switch to ON position do not start engine and observe Malfunction Indicator Light MIL a Light should blink on off quickly for approximately 3 seconds and then go off and stay off indicating initialization procedure has been successful b If light stays on or blinking ceases prematurely procedure was unsuccessful and must be repeated Possible causes for unsuccessful learning may be 1 Movement occurred in either TPS or throttle shaft during procedure 2 Crankshaft movement rotation was detected by speed sensor during procedure 3 Throttle plate position was out of learnable range recheck 1500 RPM idle speed adjustment or 4 Problem with ECU or TPS When initialization procedure has been successfully completed turn off key switch re
45. to temperature and repeat output test from step 1 Cycling voltage from 0 2 to 1 0 v should be indicated Move black voltmeter lead to engine ground location and repeat output test Same voltage 0 2 v 1 0 v should be indicated a If same voltage reading exists go on to Step 3 b If voltage output is no longer correct a bad ground path exists between sensor and engine ground Touch black lead at various points backtracking from engine ground back toward sensor watching for a voltage change at each location If correct voltage reading reappears at some point check for a problem rust corrosion loose joint or connection between that point and previous checkpoint For example if reading is too low at points on crankcase but correct voltage is indicated when black lead is touched to skin of muffler flange joints at exhaust ports become suspect With sensor still hot minimum of 400 C 752 F switch meter to Rx1K or Rx2K scale and check resistance between sensor lead and sensor case It should be less than 2 0 KO a resistance is less than 2 0 KO go to Step 4 b If resistance is greater than 2 0 KO oxygen sensor is bad replace it Allow sensor to cool less than 60 C 140 F and retest resistance with meter set on Rx1M scale With sensor cool resistance should be greater than 1 0 a If resistance is greater than 1 0 MO go to Step 5 b If resistance is less than 1 0 MO sensor is bad replace it With oxyg
46. touch wires while engine is running Spark Plug Component and Details o E o A Wire Gauge B Spark Plug C Ground Electrode D Gap NOTE Do not clean spark plug in a machine using abrasive grit Some grit could remain in spark plug and enter engine causing extensive wear and damage Engine misfire or starting problems are often caused by a spark plug that has improper gap or is in poor condition Engine is equipped with following spark plugs Refer to Maintenance for Repairs Service Parts Service Gap 0 76 mm 0 03 in Thread Size 14 mm Reach 19 1 mm 3 4 in Hex Size 15 9 mm 5 8 in Clean out spark plug recess Remove plug and replace 1 Check gap using wire feeler gauge Adjust gap to 0 76 mm 0 03 in 2 Install plug into cylinder head 3 Torque plug to 27 N m 20 ft Ib 80 Inspect each spark plug as it is removed from cylinder head Deposits on tip are an indication of general condition of piston rings valves and carburetor Normal and fouled plugs are shown in following photos Normal conditions will have light tan or gray colored deposits If center electrode is not worn plug can be set to proper gap and reused Worn e On a worn plug center electrode will be rounded and gap will be greater than specified gap Replace a worn spark plug immediately Wet Fouled A wet plug is caused
47. voltage readings are correct clear fault codes and run engine to check if any fault codes reappear To Replace Oxygen Sensor 1 5 Disconnect oxygen sensor connector from wiring harness Loosen and remove oxygen sensor from exhaust manifold muffler assembly Apply anti seize compound sparingly to threads of new oxygen sensor if none already exists DO NOT get any on tip as it will contaminate sensor Install sensor and torque to 50 60 N m 37 44 ft Ib Reconnect lead to wiring harness connector Make sure it can not contact hot surfaces moving parts etc Test run engine A malfunctioning relay can result in starting or operating difficulties Relay and related wiring can be tested as follows 1 2 56 Disconnect relay connector plug from relay Connect black lead of VOA meter to a chassis ground location Connect red lead to 86 terminal in relay connector Set meter to test resistance Rx1 Turn ignition switch from OFF to ON Meter should indicate continuity ground circuit is completed for 1 to 3 seconds Turn key switch back off a Clean connection and check wiring if circuit was not completed Set meter for DC voltage Touch red tester lead to 30 terminal in relay connector A reading of 12 volts should be indicated at all times Connect red lead of meter to 85 terminal in relay connector Turn key switch to ON position Battery voltage should be present a No voltage present indicates a
48. 02 Rev E KohlerEngines com 11 Specifications CLEARANCE SPECIFICATIONS Governor ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Governor Cross Shaft to Crankcase Running Clearance 6 mm Shaft 8 mm Shaft 0 025 0 126 mm 0 0009 0 0049 in 0 013 0 075 mm 0 0005 0 0030 in 0 025 0 126 mm 0 0009 0 0049 in Cross Shaft O D New Max Wear Limit 6 mm Shaft 8 mm Shaft 7 949 8 000 mm 0 3129 0 3149 in 7 936 mm 0 3124 in 0 013 0 075 mm 0 0005 0 0030 in 0 025 0 126 mm 0 0009 0 0049 in Governor Gear Shaft to Governor Gear Running Clearance 0 090 0 160 mm 0 0035 0 0063 in 0 015 0 140 mm 0 0006 0 0055 in Gear Shaft O D New Max Wear Limit Ignition 5 990 6 000 mm 0 2358 0 2362 in 5 977 mm 0 2353 in 5 990 6 000 mm 0 2358 0 2362 in 5 977 mm 0 2353 in Spark Plug Gap 0 76 mm 0 030 in Ignition Module Air Gap 0 28 0 33 mm 0 011 0 013 in Speed Sensor Air Gap 1 50 0 25 mm 0 059 0 010 in Crankshaft Position Sensor Air Gap 0 2 0 7 mm 0 008 0 027 in Piston Piston Rings and Piston Pin Piston to Piston Pin Running Clearance 0 006 0 017 mm 0 0002 0 0007 in 0 006 0 017 mm 0 0002 0 0007 in Pin Bore I D New Max Wear Limit 17 006 17 012 mm 0 6695 0 6698 in 17 025 mm 0 6703 in 17 006 17 012 mm 0 6695 0 6698 in 17 025 mm 0 6703 in Pin O D New Max Wear Limit
49. 2 Lubricate cylinder bore piston and piston rings with engine oil Compress rings using a piston ring compressor 3 Make sure FLY stamping on piston is facing towards flywheel side of engine Use a hammer with a rubber grip and gently tap piston into cylinder as shown Be careful that oil ring rails do not spring free between bottom of ring compressor and top of cylinder 4 Install inner rod cap to connecting rod using screws Torque in increments to 11 6 N m 103 in Ib Illustrated instructions are provided in service rod package 5 Repeat above procedure for other connecting rod and piston assembly Install Governor Cross Shaft 1 Liberally apply camshaft lubricant to each of cam lobes Lubricate camshaft bearing surfaces of crankcase and camshaft with engine oil 2 Position timing mark of crankshaft gear at 12 o clock position 3 Turn governor cross shaft clockwise until lower end of shaft contacts cylinder Make sure cross shaft remains in this position while installing camshaft 4 Slide camshaft into bearing surface of crankcase positioning timing mark of camshaft gear at 6 o clock position Make sure camshaft gear and crankshaft gear mesh with both timing marks aligned Install shim removed during disassembly onto camshaft Oil Pump Assembly 1 Lubricate governor cross shaft bearing surfaces in crankcase with engine oil 2 Slide small lower washer onto governor cross shaft and install cross
50. 5 in Ib into new holes 2 3 N m 20 in Ib into used holes Fastener Torque 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes Starter Assembly Thru Bolt Nippondenso Solenoid Shift Delco Remy Solenoid Shift 5 6 9 0 N m 49 79 in Ib 4 5 7 5 N m 40 84 in Ib 5 6 9 0 N m 49 79 in Ib Mounting Screw 16 0 N m 142 in Ib 15 3 N m 135 in Ib Brush Holder Mounting Screw Delco Remy Starter 2 5 3 3 N m 22 29 in Ib 2 5 3 3 N m 22 29 in Ib Stator Mounting Screw 6 2 N m 55 in Ib into new holes 4 0 N m 35 in Ib into used holes 6 2 N m 55 in Ib Starter Solenoid Mounting Hardware 4 0 6 0 N m 35 53 in Ib Nippondenso Starter 6 0 9 0 N m 53 79 in Ib Delco Remy Starter 4 0 6 0 N m 35 53 in Ib Nut Positive Brush Lead 8 0 11 0 N m 71 97 in Ib Nippondenso Starter 8 0 12 0 N m 71 106 in Ib Delco Remy Starter 8 0 11 0 N m 71 97 in Ib Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 24 690 02 Rev E KohlerEngines com Specifications TORQUE SPECIFICATIONS 5 ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Valve Cover Valve Cover Fastener 6 2 N m 55 in Ib Gasket Style Cover 3 4 N m 30 in Ib Black O Ring Style Cover w Shoulder Screws 5 6 N m 50 in Ib w Flange Scre
51. Circuit N A Y 51 P0261 Injector 1 Short Circuit to Ground N A Y 51 P0262 Injector 1 Short Circuit to Battery N A Y 52 P1263 Injector 2 Open Circuit N A Y 52 P0264 Injector 2 Short Circuit to Ground N A Y 52 P0265 Injector 2 Short Circuit to Batt N A Y 55 P1651 Diagnostic Lamp Open Circu N A Y 55 P1652 Bn Lamp Short Circuit to N A Y 55 P1653 Bay Lamp Short Circuit to N A Y 56 P1231 Pump Relay Open Circuit N A Y 56 P1232 Pump Relay Short Circuit to G N A Y 56 P1233 Pump Relay Short Circuit to B N A Y 61 End of Code Transmission Y Y NOTE 6 System too Lean used to be O2 Sensor Short to Ground P0131 7 System too Rich used to be O2 Sensor Control at Lower Limit P0019 Obtainable only with ECU 24 584 28 S or later Will not blink out 1 Idle Switch not used 2 Diagnostic of TPS Signal Implausible is disabled in code 3 O2 Sensor Short to Battery diagnostic detection is disabled with SAS fuel cutoff calibrated out 4 Air Temperature Sensor not used 5 Temperature Sensor Signal Implausible diagnostic detection is calibrated out with TPLAUS set to 50 C o 24 690 02 Rev E KohlerEngines com 69 EFI SYSTEM BOSCH Code 21 Component Engine Speed Sensor Fault ECU receiving inconsistent tooth count signals from speed sensor Condition Possible misfire as ECU attempts to resynchronize during which time fuel and spark calculations are not made Conclusion Engine Speed S
52. Either incandescent or LED type bulbs can be used for MIL as long as they do not draw more than 0 1 amps Bulb needs to be rated at 1 4 Watts or less or needs to have a total resistance of 140 O or more LEDs typically draw less than 0 03 amps All current fault codes will turn on MIL when engine is running Diagnostic Aid 4 CRANKSHAFT POSITION SENSOR MIL does not turn off during cranking Condition e Crankshaft position sensor e Crankshaft position sensor circuit problem pin circuits Black 4 and Black 13 e Crankshaft position sensor toothed wheel air gap e Toothed wheel e Flywheel key sheared e ECU Diagnostic Aid 5 FUEL PUMP fuel pump not turning on Condition e Main fuse e Fuel pump circuit problem pin circuits Black 9 and Grey 17 e Fuel pump module KohlerEngines com 45 EFI SYSTEM ECV Diagnostic Aid 6 IGNITION SYSTEM no spark Condition e Spark plug e Plug wire e Coil e Coil circuit s pin circuits Grey 10 and Black 1 e ECU grounds e ECU e Vehicle safety interlocks ground signal on safety wire Diagnostic Aid 7 FUEL SYSTEM ELECTRICAL no fuel delivery Condition e No fuel e Air in high pressure fuel line e Fuel valve shut OFF e Fuel filter line plugged e Injector circuit s pin circuits Black 5 and Black 6 e Injector e ECU grounds e ECU e Lift pump not working Diagnostic Aid 8 FUEL SYSTEM fuel pressure Low Fuel Pressure Condition e Low fuel e Fuel
53. Engines com 83 Electrical System FUSES This engine has 3 blade type automotive fuses Replacement fuses must have same rating as blown fuse Use fuse chart below to determine correct fuse Wire Color Fuse Rating 2 Purple Wires 30 amp Fuse 1 Red Wire w Black Stripe 1 Red Wire w White Stripe 10 amp Fuse 2 Red Wires 10 amp Fuse Fuse Replacement 1 Shut engine off and remove key Locate fuse holders 2 3 Remove fuse cover and pull out fuse 4 Inspect fuse for a solid fusible link or a broken fusible link Replace fuse if fusible link is broken If you are not sure if fusible link is broken replace fuse 5 Insert fuse into fuse holder until it is seated properly Install fuse cover 84 KohlerEngines com 24 690 02 Rev E Starter System NOTE Do not crank engine continuously for more than 10 seconds Allow a 60 second cool down period between starting attempts Failure to follow these guidelines can burn out starter motor NOTE If engine develops sufficient speed to disengage starter but does not keep running a false start engine rotation must be allowed to come to a complete stop before attempting to restart engine If starter is engaged while flywheel is rotating starter pinion and flywheel ring gear may clash and damage starter NOTE If starter does not crank engine shut off starter immediately Do not make further attempts to start engine until condition is corrected
54. Gerotor Gears D Oil Pump Assembly E Governor Shaft F Governor Washer G Governor Gear H Governor Cup I Crankshaft J Connecting Rod K Piston L Piston Pin M Piston Pin Retainer N Piston Rings Clip Governor Cross o Camshaft P Shaft a Crankcase 104 KohlerEngines com NOTE Make sure engine is assembled using all specified torque values tightening sequences and clearances Failure to observe specifications could cause severe engine wear or damage Always use new gaskets Apply a small amount of oil to threads of critical fasteners before assembly unless a Sealant or Loctite is specified or preapplied Make sure all traces of any cleaner are removed before engine is assembled and placed into operation Even small amounts of these cleaners can quickly break down lubricating properties of engine oil Check oil pan crankcase and cylinder heads to be certain that all old sealing material has been removed Use gasket remover lacquer thinner or paint remover to remove any remaining traces Clean surfaces with isopropyl alcohol acetone lacquer thinner or electrical contact cleaner Install Flywheel End Oil Seal Oil Seal Detail A 4 5 mm 177 in B Oil Seal 1 Make sure that seal bore of crankcase is clean and free of any nicks or burrs 2 Apply a light coat of engine oil to outside diameter of oil seal 3 Drive oil seal into crankcase using a seal driver Make sure oil seal is installed str
55. Hold starter assembly vertically on end housing and carefully position assembled brush holder assembly with supplied protective tube against end of commutator armature Mounting screw holes in metal clips must be up out Slide brush holder assembly down into place around commutator and install positive brush lead grommet in cutout of frame Protective tube may be saved and used for future servicing Starter reassembly when not replacing brushes brush holder assembly a Carefully unhook retaining caps from brush assemblies Do not lose springs 87 Starter System b Position brushes back in their slots so they are flush with I D of brush holder assembly Insert brush installation tool with extension or use tube described above from a prior brush installation through brush holder assembly so holes in metal mounting clips are up out c Install brush springs and snap on retainer caps d Hold starter assembly vertically on end housing and carefully place tool with extension and assembled original brush holder assembly onto end of armature shaft Slide brush holder assembly down into place around commutator install positive brush lead grommet in cutout of frame 11 Install end cap onto armature and frame aligning thin raised rib in end cap with corresponding slot in grommet of positive brush lead 12 Install thru bolts and brush holder mounting screws Torque bolts to 5 6 9 0 N m 49 79 in Ib and brush hol
56. KOHLER Command PRO ECV630 ECV749 CV735 CV26 CV745 Service Manual IMPORTANT Read all safety precautions and instructions carefully before operating equipment Refer to operating instruction of equipment that this engine powers Ensure engine is stopped and level before performing any maintenance or service 2 Safety 3 Maintenance 5 Specifications 15 Tools and Aids 18 Troubleshooting 22 Air Cleaner Intake 23 Electronic Fuel Injection EFI System ECV 48 Electronic Fuel Injection EFI System Bosch 78 Lubrication System 80 Electrical System 85 Starter System 89 Disassembly Inspection and Service 104 Reassembly 24 690 02 Rev E KohlerEngines com Safety SAFETY PRECAUTIONS A WARNING A hazard that could result in death serious injury or substantial property damage A CAUTION A hazard that could result in minor personal injury or property damage NOTE is used to notify people of important installation operation or maintenance information A WARNING Explosive Fuel can cause fires and severe burns LA k Do not fill fuel tank while engine is hot or running Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved containers in well ventilated unoccupied buildings away from sparks or flames Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition Never use gasoline as a cleaning agent A
57. MIL When light starts blinking rapidly 5 blinks per second move throttle lever to low idle speed position Check and adjust idle speed to 1500 RPM using a tachometer Lamp should continue to blink rapidly for another 30 seconds before switching to a slow blink When MIL blinks slowly do not do anything but wait until MIL shuts off This indicates that this procedure has been completed successfully Shut off engine If learn procedure was successfully completed external loads removed disconnected in Step 2 may be reconnected If procedure was unsuccessful see Steps a and b following a If during this procedure MIL goes back into blinking 4 consecutive blinks every 2 seconds engine and O sensor have cooled down and out of closed foop operation prohibiting learning from occurring Repeat Steps 6 9 b If during procedure with engine running MIL stays ON continuously for more than 15 seconds turn off ignition Then initiate fault code sequence by doing three consecutive key on key off cycles leaving t key ON in last sequence each key on key off sequence must be less than 2 5 seconds long Fault detected must be corrected before auto learn function can be re initiated PC based diagnostic tool and software may be used to read out fault code and assist with troubleshooting and repair Temperature sensor is a sealed non serviceable assembly A faulty sensor must be replaced If a blink code indicates a probl
58. N 6 If voltage is between 7 and 14 turn key switch OFF and connect an ohmmeter between terminals on pump to check for continuity a If there was no continuity between pump terminals replace fuel pump b If voltage was below 7 test wiring harness 7 f voltage at plug was good and there was continuity across pump terminals reconnect plug to pump making sure you have a good connection Turn on key switch and listen for pump to activate a If pump starts repeat steps 2 and 3 to verify correct pressure b If pump still does not operate replace it High Pressure Fuel Line High pressure fuel line is mounted to intake manifold No specific servicing is required unless operating conditions indicate that it needs replacement Thoroughly clean area around all joints and relieve any pressure before starting any disassembly Detach by removing two mounting screws wire ties and injector retaining clips Purge Port and Vent Hose Assembly No specific servicing is required for vent hose assembly or purge port unless operating conditions indicate replacement is required All components are serviced individually Abrasion sleeves on hoses should be reused or replaced when servicing vent hoses Please note vent hose routing and replicate after service or component replacement to prevent pinching or abrasion of vent hoses Only Kohler replacement parts can be used because fitting is specific to system and must be maintained Visit KohlerEngines
59. N m 100 in Ib into new holes or 7 3 N m 65 in Ib into used holes in sequence shown Note first screw is torqued a second time Install Reconnect Rectifier Regulator NOTE Rectifier regulator middle terminal B is offset not equally spaced from outer terminals AC Verify rectifier regulator plug is assembled to match terminal offset of rectifier regulator 1 Install rectifier regulator in blower housing if removed previously then secure grounding bracket against outer side of rectifier regulator with a silver Screw 2 Torque black rectifier regulator screws to 1 4 N m 12 6 in Ib and silver ground strap screw to 2 8 N m 25 in Ib into new holes or 2 3 N m 20 in Ib into used holes 3 Connect plug to rectifier regulator If purple wire was removed verify locking tang is raised on terminal and push wire terminal into plug prior to connecting to rectifier regulator KohlerEngines com 24 690 02 Rev E Install Metal Debris Screen Spring Washer Details A Metal Debris Screen B Fan C Flywheel D Spacer E Hex Bolt Verify locating tabs on back of fan are inserted into locating holes on flywheel 2 Toassist assembly find intake manifold studs with M6 thread at least 100 mm in length to be used as guide pins Insert intake manifold studs through cooling fan mounting holes and thread th
60. P Sensor ECV EFI NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connector has seal in place 1 Lightly oil MAP sensor O ring and push MAP sensor into bore in intake manifold 110 KohlerEngines com 2 Torque screw to 7 3 N m 65 in Ib 3 Push electrical connector on MAP sensor making sure a good connection is made Install Crankshaft Position Sensor NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connectors have seal in place 1 Install crankshaft position sensor and bracket assembly to crankcase posts 2 Snug screws and check air gap of sensor with a feeler gauge It must be 0 20 0 70 mm 0 008 0 027 in 3 Torque bracket screws to crankcase to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib into new holes 4 Push electrical connector on crankshaft position sensor making sure a good connection is made Install Valve Covers Torque Sequence 1 Make sure sealing surfaces are clean 2 Make sure there are no nicks or burrs on sealing surfaces 3 Install a new O ring in groove of each cover 4 Position covers on cylinder heads Locate cover with oil separator hole on cylinder 1 Install screws in each cover and finger tighten 5 Torque valve cover fasteners to Torque Model Gasket RTV 3 4 N m 30 in Ib CV Black O ring w shoulder screws 5 6 N m 50 in I
61. Remove Oil Sentry NOTE This is optional Removing Oil Sentry is not required to remove breather cover 1 Disconnect lead from Oil Sentry switch 2 Remove Oil Sentry switch from breather cover Remove Oil Temperature Sensor NOTE Unless oil temperature sensor is damaged or malfunctioning disassembly from breather cover is unnecessary 1 Disconnect lead from oil temperature sensor 2 Remove oil temperature sensor from breather cover 3 Remove breather hose from breather cover Remove Inner Baffles and Breather Cover NOTE Removing oil temperature sensor is not required to remove breather cover or inner baffles Remove screws securing inner baffles to crankcase Remove inner valley baffles Disconnect and remove oil temperature sensor Remove remaining screws from breather cover Pry under protruding edge of breather cover with a screwdriver to break gasket seal Do not pry on sealing surfaces as it could cause damage resulting in leaks 6 Remove breather cover and gasket D Fab KohlerEngines com 93 Disassembly Inspection and Service Cylinder Head Components lt TIT re IS N he A Valve Cover Valve Cover Gasket C Hex Flange Screw D Rocker Arm Piviot E Rocker Arm F Push Rod Hydraulic Lifter H Valve Cap l Valve Keeper J Valve Spring Valve Seal L m Cylinder Head M Cylinder Head N Gasket o Valve P Dowel Pin Remove Valve Cover
62. TER ELEMENT REMOVAL 8 15751165 OILFILL amp 38 G ENGINE DIPSTICK TUBE 620 5 731 Y P V MOUNTING d SES HOLE A EXHAUST FLYWHEEL SIDE PORT 1 ENO e 405 89 SHIFT STARTER 15 980 um E 9 760 OIL COOLER 4X0920 R 0254 00 10 00 B C MOUNTING HOLE A REGULATOR Pn oh ENGINE o SURFACE 73 19 93 44 559 m d A l STARTER SIDE ENGINE MOUNTING SURFACE 1391 PORTA2 PORT 1 OIL DRAIN PLUG 3 8 NPT INCH 3 24 690 02 Rev E KohlerEngines com Specifications Engine Dimensions with Low Profile Air Cleaner 427 72 Dimensions in millimeters 60 00 2 362 AIR CLEANER Sess COVER REMOVAL ENGINE MOUNTING HOLE A FLYWHEEL SIDE OIL COOLER EGULAT RECTIFIER 52 26 2 057 OIL FILTER 1 2641 1395 85 50 85 91 D EM Sc 3 382 MOUNTING YW OIL FILTER OIL DRAIN PLUG EAT 3 8 NPT INCH 28 56 7 16 20 UN Su 1 125 Y 981 1150 OIL FILTER SIDE OR aia SPARK PLUG 96 70 3 807 Inch equivalents shown in 334 62 13 174 goa 3 520 2X 72 854 77 90 2 868 3 067 50 00
63. Upper Insulator F Bi eet G High Temp Water Seal Temperature must be controlled very accurately and gas constituents measured to a high degree of accuracy for absolute sensor measurements This requires laboratory equipment to determine a good or bad sensor in field Furthermore as with most devices intermittent problems are difficult to diagnose Still with a good understanding of system and sensor it is possible to diagnose many sensor problems in field Using diagnostic software connected to ECU is a useful technique for observing sensor performance However user must understand that such software reads a signal generated by ECU If there is an ECU or wiring problem readings could be misinterpreted as a sensor problem Digital nature of signal to software means that it is not reading continuous output of sensor A voltmeter can also be used as an effective tool in diagnosing sensors It is advisable to use an electronic meter such as a digital voltmeter Simple mechanical meters may place a heavy electrical load on sensor and cause inaccurate readings Since resistance of sensor is highest at low temperatures such meters will cause largest inaccuracies when sensor is in a cool exhaust Visual Inspection 1 Lookfor a damaged or disconnected sensor to engine harness connection 2 Look for damage to sensor lead wire or associated engine wiring due to cutting chaffing or melting on a hot surface 3 Disconnect sensor con
64. WARNING Accidental Starts can cause severe injury or death Disconnect and ground spark plug lead s before 24 servicing CR A CAUTION Y Electrical Shock can cause injury ue Do not touch wires while engine is running Before working on engine or equipment disable engine as follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery WARNING Ro Rotating Parts can cause CR severe injury Stay away while engine is in operation A WARNING Hot Parts can cause severe burns Wd wem DO not touch engine while operating or just after stopping A CAUTION Damaging Crankshaft and Flywheel Can Cause Jo Personal Injury LUN Keep hands feet hair and clothing away from all moving parts to prevent injury Never operate engine with covers shrouds or guards removed Never operate engine with heat shields or guards removed Using improper procedures can lead to broken fragments Broken fragments could be thrown from engine Always observe and use precautions and procedures when installing flywheel WARNING Carbon Monoxide can cause severe nausea fainting or death Avoid inhaling exhaust fumes Engine exhaust gases contain poisonous carbon monoxide Carbon monoxide is odorless colorless and can cause death if inhaled WARNING Cleaning Solve
65. age Removing crankpin plug when crankshaft is ground provides easy access for removing any grinding deposits collected in oil passages Use these following procedures to remove and replace plug Procedure to Remove Crankshaft Plug 1 Drill a 3 16 in hole through plug in crankshaft 2 Thread a 3 4 in or 1 in long self tapping screw with a flat washer into drilled hole Flat washer must be large enough to seat against shoulder of plug bore 3 Tighten self tapping screw until it draws plug out of crankshaft Procedure to Install New Plug Use a single cylinder camshaft pin as a driver and tap plug into plug bore until it seats at bottom of bore Make sure plug is tapped in evenly to prevent leakage Remove Flywheel End Oil Seal Remove oil seal from crankcase Crankcase Inspection and Service Check all gasket surfaces to make sure they are free of gasket fragments Gasket surfaces must also be free of deep scratches or nicks Inspect main bearing if so equipped for wear or damage refer to Specifications Replace crankcase using a miniblock or short block as required Check cylinder bore wall for scoring In severe cases unburned fuel can cause scuffing and scoring of cylinder wall It washes necessary lubricating oils off piston and cylinder wall As raw fuel seeps down cylinder wall piston rings make metal to metal contact with wall Scoring of cylinder wall can also be caused by localized hot spots resul
66. aight and true in bore to depth shown Install Crankshaft 1 Lubricate crankshaft journals and connecting rod bearing surfaces with engine oil 2 Carefully slide flywheel end of crankshaft through main bearing in crankcase 24 690 02 Rev E Install Connecting Rods with Pistons and Rings Piston Detail Reassembly 3 Install nylon washer onto governor cross shaft then start push on retaining ring Hold cross shaft up in position place a 0 50 mm 0 020 in feeler gauge on top of nylon washer and push retaining ring down shaft to secure Remove feeler gauge which will have established proper end play Install Camshaft A Cylinder 1 B Cylinder 2 NOTE Cylinders are numbered on crankcase Make sure to install piston connecting rod and end cap into its appropriate cylinder bore as previously marked at disassembly Do not mix end caps and connecting rods NOTE Proper orientation of piston connecting rod assemblies inside engine is extremely important Improper orientation can cause extensive wear or damage Be certain pistons and connecting rods are assembled exactly as shown NOTE Align chamfer of connecting rod with chamfer of its mating end cap When installed flat faces of connecting rods should face each other Faces with raised rib should be toward outside 1 Stagger piston rings in grooves until end gaps are 120 apart Oil ring rails should also be staggered
67. alant with Teflon Loctite 592 PST Thread Sealant or equivalent to threads of Oil Sentry switch and install it into breather cover Torque to 4 5 N m 40 in Ib Connect wire lead green to Oil Sentry terminal Install Blower Housing and Outer Baffles NOTE Do not completely tighten screws until all items 1 112 are installed to allow shifting for hole alignment Slide blower housing into position over front edge of inner baffles Start a few screws to hold it in place 2 Position outer baffles and secure using M6 screws Install M6 screws 20 mm long into intake port side of cylinder heads including any lifting strap Install M6 screws 16 mm long into exhaust port side of cylinder head Install short M5 screws 10 mm long in upper mounting holes of outer baffles into backing plate Be sure any leads are routed out through proper offsets or notches so they will not be pinched between blower housing and baffles 3 Insert and tighten all remaining blower housing and baffle screws with exception of rectifier regulator grounding bracket screw Torque all blower housing and baffle M6 screws assembled into aluminum to 10 7 N m 95 in Ib for a new hole or 7 3 N m 65 in Ib for a used hole Torque all blower housing and baffle M5 screws assembled into sheet metal backing plate to 2 8 N m 25 in Ib for new holes or 2 3 N m 20 in Ib for used holes 4 Torque breather cover screws to 11 3
68. alues are not within specifications or a momentary short or open circuit was detected during rotation step 4 TPS needs to be replaced go to step 7 6 Check TPS circuits input ground between TPS plug and main harness connector for continuity damage etc See chart on pages 24 Pin MSE 1 0 Plastic Cased ECU Pin Circuits Z8 and 4 32 Pin MSE 1 1 Plastic Cased ECU Pin Circuits Z8 and 4 a Repair or replace as required b Turn idle speed screw back in to its original setting c Reconnect connector plugs start engine and retest system operation 7 Remove two mounting screws from TPS Save screws for reuse Remove and discard faulty TPS Install replacement TPS and secure with original mounting screws a Reconnect both connector plugs b Perform appropriate TPS Initialization Procedure integrating new sensor to ECU TPS Initialization Procedure For 24 Pin MSE 1 0 Plastic Cased ECU only 1 Check that basic engine all sensors fuel fuel pressure and battery are good and functionally within specifications Important 2 Remove disconnect ALL external loads from engine belts pumps electric PTO clutch alternator rectifier regulator etc 3 Start engine and allow it to warm up for 5 10 minutes so oil temperature is above 55 C 130 F 4 Move throttle control to idle position and allow engine to stabilize for a minimum of one minute 5 Install a heavy rubber band around
69. an be found at KohlerEngines com 24 690 02 Rev E KohlerEngines com Specifications TORQUE SPECIFICATIONS ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Oil Temperature Sensor 7 3 N m 65 in Ib Oil Drain Plug 13 6 N m 10 ft Ib Cylinder Head Hex Flange Nut torque in 2 increments Head Bolt torque in 2 increments first to 16 9 N m 150 in Ib finally to 33 9 N m 300 in Ib first to 22 6 N m 200 in Ib finally to 41 8 N m 370 in Ib Rocker Arm Screw 11 9 N m 105 in Ib 11 3 N m 100 in Ib Fan Flywheel Fan Fastener 9 9 N m 88 in Ib Flywheel Retaining Screw 71 6 N m 52 8 ft Ib 66 4 N m 49 ft Ib Fuel Pump Module Baffle Fastener 11 9 N m 105 in Ib Module Fastener Pulse Pump Bracket Fastener 9 2 N m 81 in Ib 2 1 N m 25 in Ib Pulse Pump Fastener to Bracket 7 3 N m 68 in Ib into new holes 6 2 N m 55 in Ib into used holes Governor Lever Nut Ignition 7 1 N m 63 in Ib 6 8 N m 60 in Ib Spark Plug 27 N m 20 ft Ib Coil Fastener Ignition Module Fastener 10 2 N m 90 in Ib 4 0 6 2 N m 35 55 in Ib Crankshaft Position Sensor Screw 6 2 N m 55 in Ib Crankshaft Position Sensor Bracket Screw 7 3 N m 65 in Ib Electronic Control Unit Screw 6 2 N m 55 in Ib Rectifier Regulator Ground Stra
70. assembly If diagnosis indicates a bad sensor complete replacement is necessary If a blink code indicates a problem with TPS it can be tested as follows 1 Counting number of turns back out idle speed adjusting screw counterclockwise until throttle plates can be closed completely 2 Disconnect main harness connector from ECU but leave TPS mounted to throttle body manifold 3 Connect ohmmeter leads as follows See charts on pages 63 and 65 24 Pin MSE 1 0 Plastic Cased ECU Red positive ohmmeter lead to 8 pin terminal and Black negative ohmmeter lead to 4 pin terminal 32 Pin MSE 1 1 Plastic Cased ECU Red positive ohmmeter lead to 8 pin terminal and Black negative ohmmeter lead to 4 pin terminal Hold throttle closed and check resistance It should be 800 1200 O 4 Leave leads connected to pin terminals as described in step 3 Rotate throttle shaft slowly counterclockwise to full throttle position Monitor dial during rotation for indication of any momentary short or open circuits Note resistance at full throttle position It should be 1800 3000 O 5 Disconnect main wiring harness connector from TPS leaving TPS assembled to manifold Refer to chart below and perform resistance checks indicated between terminals in TPS switch with throttle in positions specified 24 690 02 Rev E If resistance values in steps 3 4 and 5 are within specifications go to step 6 If resistance v
71. at top dead center TDC of compression stroke Hold engine in this position while testing Holding tool supplied with tester can be used if PTO end of crankshaft is accessible Lock holding tool onto crankshaft Install a 3 8 in breaker bar into hole slot of holding tool so it is perpendicular to both holding tool and crankshaft PTO If flywheel end is more accessible use a breaker bar and socket on flywheel nut screw to hold it in position An assistant may be needed to hold breaker bar during testing If engine is mounted in a piece of equipment it may be possible to hold it by clamping or wedging a driven component Just be certain that engine cannot rotate off of TDC in either direction 4 Install adapter into spark plug hole but do not attach it to tester at this time 5 Turn regulator knob completely counterclockwise 6 Connect an air source of at least 50 psi to tester 7 Turn regulator knob clockwise increase direction until gauge needle is in yellow set area at low end of scale 8 Connect tester quick connect to adapter hose While firmly holding engine at TDC gradually open tester valve Note gauge reading and listen for escaping air at combustion air intake exhaust outlet and crankcase breather Condition Conclusion Air escaping from crankcase breather Ring or cylinder worn Air escaping from exhaust system Defective exhaust valve improper seating Air escaping from intake Defective intake valve improper se
72. ating Gauge reading in low green zone Piston rings and cylinder in good condition Gauge reading in moderate yellow zone Engine is still usable but there is some wear present Customer should start planning for overhaul or replacement Gauge reading in high red zone Rings and or cylinder have considerable wear Engine should be reconditioned or replaced 24 690 02 Rev E KohlerEngines com 21 Air Cleaner Intake AIR CLEANER These systems are CARB EPA certified and components should not be altered or modified in any way Low Profile Air Cleaner Components A Air Cleaner Cover B Air Cleaner Knob C Wing Nut D Element Cover E Rubber Seal F Precleaner G Paper Element H Air Cleaner Base Heavy Duty Air Cleaner Components L Air Cleaner Housing M Element N End Cap o Dust Ejector Valve P Retaining Clip Q Inner Element R Ejector Area S Inlet Screen T Filter Minder 22 KohlerEngines com NOTE Operating engine with loose or damaged air cleaner components could cause premature wear and failure Replace all bent or damaged components NOTE Paper element cannot be blown out with compressed air Low Profile Loosen knob and remove air cleaner cover Precleaner 1 Remove precleaner from paper element 2 Replace or wash precleaner in warm water with detergent Rinse and allow to air dry 3 Saturate precleaner with new engine oil squeeze ou
73. available Starter Brush Holding Tool Solenoid Shift Kohler 25 761 20 S Kohler 25 761 41 S Design Technology Inc DTI 031 DTI 033 Kohler 25 761 40 S SE Tools KLR 82411 SE Tools KLR 82416 Triad OHC Timing Tool Set For holding cam gears and crankshaft in timed position while installing timing belt Kohler 28 761 01 S Valve Guide Reamer K and M Series For properly sizing valve guides after installation Design Technology Inc DTI K828 Valve Guide Reamer O S Command Series For reaming worn valve guides to accept replacement oversize valves Can be used in low speed drill press or with handle below for hand reaming Reamer Handle For hand reaming using Kohler 25 455 12 S reamer Valve Guide Service Kit Courage Aegis Command OHC For servicing worn valve guides AIDS Description Kohler 25 455 12 S Design Technology Inc SE Tools KLR 82415 Source Part No Camshaft Lubricant Valspar ZZ613 Kohler 25 357 14 S Dielectric Grease GE Novaguard G661 Kohler 25 357 11 S Dielectric Grease Loctite 51360 Kohler Electric Starter Drive Lubricant Inertia Drive Kohler 52 357 01 S Kohler Electric Starter Drive Lubricant Solenoid Shift Kohler 52 357 02 S RTV Silicone Sealant Loctite 5900 Heavy Body in 4 oz aerosol dispenser Only oxime based oil resistant RTV sealants such as those listed are approved for use Loctite Nos 5900 or 5910 are re
74. ay and locate terminal 87 in connector 3 Using an ohmmeter set on Rx1 scale check resistance in circuits as follows 24 Pin MSE 1 0 Plastic Cased ECU Check between terminal 87 and pin 22 for coil 1 Repeat test between terminal 87 and pin 23 for coil 2 32 Pin MSE 1 1 Plastic Cased ECU Check between terminal 87 and pin 30 for coil 1 Repeat test between terminal 87 and pin 31 for coil 2 A reading of 1 8 4 0 O in each test indicates that wiring and coil primary circuits are OK a If reading s are not within specified range check and clean connections and retest 58 KohlerEngines com b If reading s are still not within specified range test coils separately from main harness as follows 1 Disconnect red and black primary leads from coil terminals 2 Connect an ohmmeter set on Rx1 scale to primary terminals Primary resistance should be 1 8 2 5 O 3 Disconnect secondary lead from spark plug Connect an ohmmeter set on Rx10K scale between spark plug boot terminal and red primary terminal Secondary resistance should be 13 000 17 500 O 4 If secondary resistance is not within specified range unscrew spark plug lead nut from coil secondary tower and remove plug lead Repeat step b 3 testing from secondary tower terminal to red primary terminal If resistance is now correct coil is good but spark plug lead is faulty replace lead If step b 2 resistance was incorrect and or secondary resistan
75. b CV w screws and spacers 9 9 N m 88 in Ib Yellow or Brown O ring CV w integral spacers 6 2 N m 55 in Ib ECV 24 690 02 Rev E Reassembly External Engine Components A C Outer Baffle D Rectifier Regulator E G Oil Temperature Sensor Breather Cover I Breather Cover Gasket 24 690 02 Rev E KohlerEngines com 111 Reassembly Install Breather Cover and Inner Baffles Torque Sequence Be sure sealing surfaces of crankcase and breather cover are clean of old gasket material Do not scrape surfaces as this could result in leakage Use a new gasket when installing breather cover Check to make sure there are no nicks or burrs on sealing surfaces Position breather gasket and cover on crankcase Install screws in locations 3 and 4 Finger tighten at this time Install inner baffles using remaining screws and finger tighten Do not torque screws at this time they will be tightened after blower housing Install Oil Temperature Sensor ECV EFI NOTE Ensure part is clean undamaged and free of debris and make sure electrical connector has seal in place Lightly lubricate oil temperature sensor O ring and install oil temperature sensor into breather cover Torque sensor to 7 3 N m 65 in Ib Push electrical connector on oil temperature sensor making sure a good connection is made Install Oil Sentry If equipped 1 2 Apply pipe se
76. ce is still incorrect coil is faulty and needs to be replaced Wiring harness used in EFI system connects electrical components providing current and ground paths for System to operate All input and output signaling occurs through a special all weather connector that attaches and locks to ECU Condition of wiring connectors and terminal connections is essential to system function and performance Corrosion moisture and poor connections are more likely cause of operating problems and system errors than an actual component Fuel Pump Fuel pumps are non serviceable and must be replaced if determined to be faulty If a fuel delivery problem is suspected make certain pump is being activated through relay all electrical connections are properly secured fuses are good and a minimum of 7 0 volts is being supplied If during cranking voltage drops below 7 0 volts a reduction of fuel pressure may occur resulting in a lean starting condition If required testing fuel pump and relay may be conducted 1 Connect black hose of Pressure Tester part of EFI Service Kit see Tools and Aids to test valve in fuel rail Route clear hose into a portable gasoline container or equipment fuel tank 2 Turn on key switch to activate pump and check system pressure on gauge If system pressure of 39 psi 3 is observed relay fuel pump and regulator are working properly Turn key switch off and depress valve button on tester to relieve syst
77. ceeded ECU suppresses injection signals cutting off fuel flow This process repeats itself in rapid succession limiting operation to preset maximum Wiring harness used in EFI system connects electrical components providing current and ground paths for system to operate All input and output signaling occurs through two special all weather connectors that attach and lock to ECU Connectors are Black and Grey and keyed differently to prevent being attached to ECU incorrectly Condition of wiring connectors and terminal connections is essential to system function and performance Corrosion moisture and poor connections are as likely cause of operating problems and system errors as an actual component Refer to Electrical System for additional information EFI system is a 12 VDC negative ground system designed to operate down to a minimum of 6 0 volts If system voltage drops below this level operation of voltage sensitive components such as ECU fuel pump ignition coils and injectors will be intermittent or disrupted causing erratic operation or hard starting A fully charged 12 volt battery with a minimum of 350 cold cranking amps is important in maintaining steady and reliable system operation Battery condition and state of charge should always be checked first when troubleshooting an operational problem Keep in mind that EFl related problems are often caused by wiring harness or connections Even small amounts of corrosio
78. ch governor spring in marked hole 6 Start engine and allow it to fully warm up and establish closed loop operation approximately 5 10 min Check speed settings and adjust as necessary first low idle speed and then high speed setting TROUBLESHOOTING Troubleshooting Guide Condition Possible Cause Fuel pump not running Faulty spark plugs Old stale fuel Incorrect fuel pressure Engine Starts Hard Speed sensor loose or faulty or Fails to Start TPS offset incorrect initialization When Cold Engine temperature sensor faulty Engine temp sensor faulty Faulty coils Low system voltage Faulty injectors Faulty spark plugs Fuel pump not running Fuel pressure low Insufficient fuel delivery Engine starts hard or fails to start TPS offset incorrect Initialization when hot Speed sensor loose or faulty TPS faulty Engine temperature sensor faulty Faulty injectors Faulty spark plugs Insufficient fuel delivery eee Mn Eis TPS offset incorrect idles rou co oF Wan TPS faulty Faulty engine temperature sensor Faulty injectors Fuel injector s fuel filter fuel line or fuel pick up dirty restricted Dirty air cleaner Insufficient fuel pressure or fuel delivery Engine misses Vacuum intake air leak hesitates or stalls under load Improper governor setting adjustment or operation Speed sensor malfun
79. ched to cylinder heads Slide any wiring harness clips onto appropriate bolts before installing Make sure gaskets are in proper orientation Using sequence shown torque screws in 2 stages first to 7 8 N m 69 in Ib then to 10 5 N m 93 in Ib 2 Install ground terminal to crankcase post with a silver screw Torque to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib in new holes 3 Install wire harness clip to other crankcase post Torque to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib in new holes 4 Place wire harness conduit in clip and snap clip together Install Fuel Injectors NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connectors have seal in place O rings and retaining clips should be replaced any time fuel injector is separated from its normal mounting position 1 Lightly lubricate fuel injector O rings with clean engine oil 2 Push retaining clip onto fuel injector aligning clip as shown 3 Press fuel injector into fuel injector cap until retaining clip snaps into place 4 Press fuel injector into bore in intake manifold and rotate to original position 5 Install fuel injector cap screw into intake manifold and torque to 7 3 N m 65 in Ib 6 Push electrical connector on fuel injector making sure a good connection is made 7 Repeat steps 1 through 6 for other fuel injector Install Manifold Absolute Pressure MA
80. circuit is open shorted to ground or shorted to battery Condition Engine will run very poorly with only one cylinder functioning Conclusion Injector Related e Injector coil shorted or opened Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin 15 to injector pin 2 ECU pin 28 to fuel pump relay pin 86 Note after key off then key on code 56 would be set also Fuel pump relay pin 87 to injector pin 1 e Opened main fuse F1 Fuel Pump Relay Related e Bad fuel pump relay Primary side functional but pin 30 to pin 87 remains open Primary side pin 85 to pin 86 is open or shorted during engine operation Note after key off then key on code 56 would be set also ECU Related e Circuit controlling injector 42 damaged e Circuit controlling fuel pump relay damaged Code 55 32 Pin MSE 1 1 Plastic Cased ECU only Component MIL Diagnostic lamp circuit open shorted to ground or shorted to battery Fault MIL is not functioning because circuit is open shorted to ground or shorted to battery Condition Engine will run normally if no other errors are present Conclusion MIL diagnostic lamp Related e MIL element opened or element shorted to ground e Lamp missing Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin 29 to lamp open or shorted Vehicle Wiring Harness Related e Broken or shorted wire i
81. clicking sound with a screwdriver or mechanic s stethoscope NOTE Do not apply voltage to fuel injector s Excessive voltage will burn out injector s Do not ground injector s with ignition ON Injector s will open turn on if relay is energized 3 Disconnect electrical connector from an injector and listen for a change in idle performance only running on one cylinder or a change in injector noise or vibration If an injector is not operating it can indicate either a bad injector or a wiring electrical connection problem Check as follows 1 Disconnect electrical connector from both injectors Plug a 12 volt noid light part of EFI Service Kit see Tools and Aids into one connector 2 Make sure all safety switch requirements are met Crank engine and check for flashing of test light Repeat test at other connector a If flashing occurs use an ohmmeter Rx1 scale and check resistance of each injector across two terminals Proper resistance is 12 20 O If injector resistance is correct check whether connector and injector terminals are making a good connection If resistance is not correct replace injector following steps 1 8 and 13 16 below b If no flashing occurs reattach connectors to both injectors Disconnect main harness connector from ECU and connector from relay Set ohmmeter to Rx1 scale and check injector circuit resistance as follows 24 Pin MSE 1 0 Plastic Cased ECU Check resistance between r
82. com for recommended Kohler replacement parts Throttle Body Intake Manifold Assembly NOTE ECU Reset is required if throttle body is replaced Throttle body is serviced as an assembly with throttle shaft TPS throttle plate and idle speed adjusting screw installed Throttle shaft rotates on needle bearings non serviceable capped with seals to prevent air leaks TROUBLESHOOTING Troubleshooting Guide Condition Possible Cause Fuel pump not running Faulty spark plugs Old stale fuel Incorrect fuel pressure Crankshaft position sensor loose or faulty Engine Starts Hard TPS set incorrect ECU Reset and TPS Learn or Fails to Start TPS faulty When Cold Engine temp sensor faulty Faulty coils Low system voltage Faulty injectors Faulty battery Loose or corroded connections 24 690 02 Rev E KohlerEngines com 37 EFI SYSTEM ECV Troubleshooting Guide Condition Possible Cause Engine Starts Hard or Fails to Start When Hot Faulty spark plugs Fuel pump not running Fuel pressure low Insufficient fuel delivery TPS set incorrect ECU Reset and TPS Initialization Crankshaft position sensor loose or faulty TPS faulty Engine temp sensor faulty Faulty injectors Engine Stalls or Idles Roughly cold or warm Faulty spark plugs Insufficient fuel delivery TPS set incorrect TPS faulty Faulty e
83. commended for best sealing characteristics Kohler 25 597 07 S Loctite 59109 Loctite Ultra Black 5987 Loctite Ultra Blue 587 Loctite Ultra Copper 59207 Spline Drive Lubricant Kohler 25 357 12 S 16 KohlerEngines com 24 690 02 Rev E Tools and Aids FLYWHEEL HOLDING TOOL ROCKER ARM CRANKSHAFT TOOL A flywheel holding tool can be made out of an old junk A spanner wrench to lift rocker arms or turn crankshaft flywheel ring gear and used in place of a strap wrench may be made out of an old junk connecting rod 1 Using an abrasive cut off wheel cut out a six tooth 1 Find a used connecting rod from a 10 HP or larger segment of ring gear as shown engine Remove and discard rod cap 2 Grind off any burrs or sharp edges 2 Remove studs of a Posi Lock rod or grind off l 3 Invert segment and place it between ignition bosses SG steps of a Command rod so joint surface is on crankcase so tool teeth engage flywheel ring a gear teeth Bosses will lock tool and flywheel in 3 Find a 1 in long capscrew with correct thread size to position for loosening tightening or removing with a match threads in connecting rod puller 4 Use a flat washer with correct I D to slip on capscrew and approximately 1 in O D Assemble capscrew and washer to joint surface of rod 24 690 02 Rev E KohlerEngines com 17 Troubleshooting TROUBLESHOOTING GUIDE When troubles occur be sure to check simple caus
84. ction TPS faulty mounting problem or TPS Initialization Procedure incorrect Bad coil s spark plug s or wires 24 690 02 Rev E KohlerEngines com 61 EFI SYSTEM BOSCH TROUBLESHOOTING Troubleshooting Guide Condition Possible Cause Faulty malfunctioning ignition system Dirty air filter Insufficient fuel delivery Improper governor adjustment Low Power Plugged restricted exhaust One injector not working Basic engine problem exists TPS faulty or mounting exist s Throttle plates in throttle body intake manifold not fully opening to WOT stop if so equipped Electrical System NOTE When performing voltage or continuity tests avoid putting excessive pressure on or against connector pins Flat pin probes are recommended for testing to avoid spreading or bending terminals EFI system is a 12 VDC negative ground system designed to operate down to a minimum of 7 0 volts If system voltage drops below this level operation of voltage sensitive components such as ECU fuel pump and injectors will be intermittent or disrupted causing erratic operation or hard starting A fully charged 12 volt battery with a minimum of 350 cold cranking amps is important in maintaining steady and reliable system operation Battery condition and state of charge should always be checked first when troubleshooting an operational problem Keep in mind that EFl related problems are more often cause
85. ctrical System Reset and TPS Learn procedure Engine is now completely reassembled Before starting or operating engine be sure to follow steps below 1 Make sure all hardware is tightened securely 2 Make sure oil drain plugs Oil Sentry pressure Switch and a new oil filter are installed 3 Fill crankcase with correct amount weight and type of oil Refer to oil recommendations and procedures in Maintenance Specifications and Lubrication System 4 Adjust idle speed adjusting screw as necessary Refer to Fuel System 5 Turn on fuel supply KohlerEngines com 117 Reassembly Sensitivity Adjustment A Governor Lever B Hole 1 C Hole 2 D Hole 3 E Hole 4 Governor sensitivity is adjusted by repositioning governor spring in holes of governor lever If speed surging occurs with a change in engine load governor is set too sensitive If a big drop in speed occurs when normal load is applied governor should be set for greater sensitivity Adjust as follows 1 To increase sensitivity move spring closer to governor lever pivot point 2 To decrease sensitivity move spring away from governor lever pivot point Testing Engine It is recommended engine be operated on a stand or bench prior to installation in piece of equipment 1 Start engine inspect for leaks and check to make certain that oil pressure 20 psi or more is present Run engine at idle for 2 3 minutes then
86. ctrode to optimum temperature in about 10 seconds Oxygen sensor receives ground through wire eliminating need for proper grounding through muffler If problems indicate a bad oxygen sensor check all connections and wire harness Oxygen sensor can also be contaminated by leaded fuel certain RTV and or other silicone compounds fuel injector cleaners etc Use only those products indicated as O2 Sensor Safe Manifold absolute pressure MAP sensor provides immediate manifold pressure information to ECU MAP measures difference in pressure between outside atmosphere and vacuum level inside intake manifold and monitors pressure in manifold as primary means of detecting load Data is used to calculate air density and determine engine s mass air flow rate which in turn determines required ideal fueling MAP also stores instant barometric pressure reading when key is turned ON Fuel injectors mount into intake manifold and high pressure fuel line attaches to them at top end Replaceable O rings on both ends of injector prevent external fuel leakage and also insulate it from heat and vibration A special clip connects each injector to high pressure fuel line and holds it in place O rings and retaining clip must be replaced any time fuel injector is separated from its normal mounting position When key switch is on fuel pump module will pressurize high pressure fuel line to 39 psi and voltage is present at injector At proper instant ECU co
87. d e Sensor malfunction e Vacuum leaks from loose manifold or sensor Wire Harness Related e Poor grounding or open circuit e Wire harness and connectors loose damaged or corroded e Pin circuit wiring or connectors at Black 10 11 and 16 Bad TPS Learn 24 690 02 Rev E EFI SYSTEM ECV Code 0108 Code 0118 Component Manifold Absolute Pressure Sensor Component Coolant Oil Sensor Fault MAP Circuit High Voltage Fault Coolant Oil Temperature Sensor Circuit Condition Intake manifold leak shorted connection High Voltage or Open or faulty sensor Condition Shorted connection faulty sensor open Conclusion MAP Sensor Related connection or broken wire e Sensor malfunction Conclusion Temperature Sensor Related e Vacuum leaks from loose manifold or e Sensor wiring or connection sensor Engine Wiring Harness Related Wire Harness Related e Pin circuits ECU Black pin 10 and 14 e Poor grounding may be damaged e Pin circuit wiring or connectors at Black e ECU to harness connection problem or 11 broken wire Bad TPS Learn System Related e Engine is operating above 176 C Code 0112 350 F temperature sensor limit Component Intake Air Temperature Sensor _ Code 0122 Fault Intake Air Temperature Sensor Circuit Low Voltage Component Throttle Position Sensor TPS Condition Shorted connection fa
88. d by excessive oil consumption and blue exhaust smoke When rings fail oil is allowed to enter combustion chamber where it is burned along with fuel High oil consumption can also occur when piston ring end gap is incorrect because ring cannot properly conform to cylinder wall under this condition Oil control is also lost when ring gaps are not staggered during installation When cylinder temperatures get too high lacquer and varnish collect on pistons causing rings to stick which results in rapid wear A worn ring usually takes on a shiny or bright appearance Scratches on rings and pistons are caused by abrasive material such as carbon dirt or pieces of hard metal Detonation damage occurs when a portion of fuel charge ignites spontaneously from heat and pressure shortly after ignition This creates 2 flame fronts which meet and explode to create extreme hammering pressures on a specific area of piston Detonation generally occurs from using low octane fuels Preignition or ignition of fuel charge before timed spark can cause damage similar to detonation Preignition damage is often more severe than detonation damage Preignition is caused by a hot spot in combustion chamber from sources such as glowing carbon deposits blocked cooling fins an improperly seated valve or wrong spark plug s Replacement pistons are available in STD bore size and in 0 25 mm 0 010 in and 0 50 mm 0 020 in oversize Replacement pistons inclu
89. d by wiring harness or connections than by EFI components Even small amounts of corrosion or oxidation on terminals can interfere with milliamp currents used in system operation Cleaning connectors and grounds will solve problems in many cases In an emergency situation simply disconnecting and reconnecting connectors may clean up contacts enough to restore operation at least temporarily If a fault code indicates a problem with an electrical component disconnect ECU connector and test for continuity between component connector terminals and corresponding terminals in ECU connector using an ohmmeter Little or no resistance should be measured indicating that wiring of that particular circuit is OK An illustrated listing of numerical terminal locations for each style of ECU connector is provided on pages 63 and 65 62 KohlerEngines com 24 690 02 Rev E EFI SYSTEM BOSCH 24 Pin MSE 1 0 Plastic Cased ECU Systems Pin Component 1 Permanent Battery Voltage 2 Switched lgnition Voltage 3 Safety Switch 4 Throttle Position Sensor TPS and Temperature Sensor Ground 5 Not Used o o 6 Oil Temperature Sensor Input 7 Not Used vk 8 Throttle Position Sensor TPS Input o O 9 Speed Sensor Input o O 10 Speed Sensor Ground o O 11 Oxygen Sensor Input 12 Not Used Oxygen Sensor Ground if needed dia 13 Diagnostic Line o o 14 Throttle Position Supply Voltage o o 15 Battery Ground o O 16 KSE Output o o 17 Injector 2 Output 18 Main Re
90. d ground spark plug leads 2 Complete all safety interlock requirements and crank engine for approximately 3 seconds 3 Remove spark plugs and check for fuel at tips a If there is fuel at tips of spark plugs fuel pump and injectors are operating b If there is no fuel at tips of spark plugs check following 1 Make sure fuel tank contains clean fresh proper fuel 2 Make sure that vent in fuel tank is open 3 Make sure fuel tank valve if so equipped is fully opened 4 Make sure battery is supplying proper voltage 5 Check that fuses are good and that all electrical and fuel line connections are good 6 Test fuel pump and relay operation as described earlier under Fuel Pump ECU continuously monitors engine operation against preset performance limits If operation is outside limits ECU activates MIL and stores a diagnostic code in its fault memory If component or system returns to proper function ECU will eventually self clear fault code and turn off MIL If MIL stays illuminated it warns customer that dealer service is required Upon receipt dealer technician can access fault code s to help determine what portion of system is malfunctioning 2 digit blink codes available based upon style of ECU are listed on pages Codes are accessed through key switch and displayed as blinks or flashes of MIL Access codes as follows 1 Start with key switch off 2 Turn key switch on off on off on leaving it
91. d to 1 AC terminal and reconnect it to other AC terminal Repeat test If OK green light comes on again used part is good and may be an inadequate ground lead connection Make certain connection location is clean and clamp is secure Other lights come on Troubleshooting Guide NOTE Aflashing LOW light can also occur as a result of Rectifier regulator is faulty and should not be used 20 25 Amp Battery Charging System NOTE Always zero ohmmeter on each scale before testing to ensure accurate readings Voltage tests should be made with engine running at 3600 RPM no load Battery must be good and fully charged When problems occur in keeping battery charged or battery charges at too high a rate problem can usually be found somewhere in charging system or with battery To test charging system for no charge to battery 1 Insert an ammeter in B lead from rectifier regulator With engine running at 3600 RPM and B at terminal on rectifier regulator to ground using a DC voltmeter If voltage is 13 8 volts or more place a minimum load of 5 amps turn on lights if 60 watts or more or place a 2 5 ohm 100 watt resistor across battery terminals on battery to reduce voltage Observe ammeter Conclusion Charging system is OK and battery was fully charged Test stator and rectifier regulator steps 2 and 3 Condition Charge rate increases when load is applied Charge rate does not i
92. de new piston ring sets and new piston pins Replacement ring sets are also available separately for STD 0 25 mm 0 010 in and 0 50 mm 0 020 in oversize pistons Always use new piston rings when installing pistons Never use old rings Some important points to remember when servicing piston rings 1 Oylinder bore must be deglazed before service ring sets are used 2 If cylinder bore does not need reboring and if old piston is within wear limits and free of score or scuff marks old piston may be reused 3 Remove old rings and clean up grooves Never reuse old rings 4 Before installing new rings on piston place top 2 rings each in turn in its running area in cylinder bore and check end gap Compare ring gap to tolerance listed in Specifications 5 After installing new compression top and middle rings on piston check piston to ring side clearance Compare clearance to tolerance listed in Specifications If side clearance is greater than specified a new piston must be used Install New Piston Rings NOTE Rings must be installed correctly Ring installation instructions are usually included with new ring sets Follow instructions carefully Use a piston ring expander to install rings Install bottom oil control ring first and top compression ring last 24 690 02 Rev E Disassembly Inspection and Service To install new piston rings proceed as follows 1 Oil Control Ring Bottom Groove Install
93. der mounting screws to 2 5 3 3 N m 22 29 in Ib 13 Hook plunger behind upper end of drive lever and install spring into solenoid Insert mounting screws through holes in drive end cap Use these to hold solenoid gasket in position then mount solenoid Torque screws to 4 0 6 0 N m 35 53 in Ib 14 Connect positive brush lead bracket to solenoid and secure with nut Torque nut to 8 11 N m 71 97 in Ib Do not overtighten Solenoid Tests NOTE DO NOT leave 12 volt test leads connected to solenoid for any time over what is necessary for performing each of individual tests Internal damage to solenoid may occur Disconnect all leads from solenoid including positive brush lead attached to lower stud terminal Remove mounting hardware and separate solenoid from starter for testing To test solenoid pull in coil plunger Actuation 1 Use a 12 volt power supply and 2 test leads 2 Connect 1 lead to flat spade S start terminal on solenoid Momentarily connect other lead to lower large post terminal When connection is made solenoid should energize audible click and plunger retract Repeat test several times Continuity 1 Use an ohmmeter set to audible or Rx2K scale and connect 2 ohmmeter leads to 2 large post terminals 2 Perform solenoid pull in coil plunger actuation test and check for continuity Ohmmeter should indicate continuity Repeat test several times To test solenoid hold in coil Function 1 Connecta 12
94. dium Suspunaif porn sy iof dp e 8 310N Aal snifus zer Yi HSN Jem a enee rper mb Zog SION NTN mg 3 310N ONnONO 33 ay conowia ees T eZ 21 t ice uo H 20895 josuaS J 0334S 2NON3 gt vonisod oumosoduoj Z MOLEN 1 MOLOJCN d vol 3 ue iz 6 oz pue suid SdL 01 sea euj Bujuapas 5 S 15 sounbo1 uoe AAD Sd AU jo OPIS YOUS ANOJI eui WO peviej Se eroi Uado 9pyM o s ue 9ipi WOM Sd eu JO Volet M22 40 8 UMOUS UOHD ULOD SdL Jsues LOMSOd AHONI IUL zy X a A 5 ALIO 9BeuoA Bug 2 PIOI e up IPA 2P AGL 03 5 fue unejado PWN LE e E teed uj poz SWO 009 Aoje wjxodde jo joj 9 e sambos SUL pesn eque qa vu m g Oz e peuondo dwe juessepueau YSO ATL eq ue Vy dwej IR pur ngem 0 un unn uauasv L UVA aed persi e eq oj ex OL pue G suid saya josues paads 5 Aen ae saa jjo payjreds espueujo ssoyur Bupyues gt Guunp uonasado NOF eui 20 wn wujus AL oq Lem afp weiss out Bogis Gung Kio wow aandepe eu uum w OJ vu Z JO Mp El 9 UM Ai JO go wasis ununuru e ureyureu jsnu KJeneq eu uongiedo ui jou UDM JOJIBULOJ e3399 eui wo Keme eBeuppup sodod Seu OF UMOP SSPUJEU BIM PUL uj PUNOU S Sussnou CO eui reu pepueuuooe 57 I esjou uiejs s eauj2eje quanaid oi pasn aq nu j00q 40 aupa ryd yieds anysisay e sayna uy Ered weds ansis a v SSOLUVY BVA SISSEYI JO ujBue 43 Wor pasamod eq jou peus bd uoy o spins PROJ siana pubes jue aud oj JaMod au 043002 0j pasn aq Lea e jey papueuuo eJ si y wo
95. divides regulator into two separate sections fuel chamber and pressure regulating chamber Pressure regulating spring presses against valve holder part of diaphragm pressing valve against valve seat Combination of atmospheric pressure and regulating spring tension equals desired operating pressure Any time fuel pressure against bottom of diaphragm exceeds desired top pressure valve opens relieving excess pressure returning excess fuel back to tank Fuel rail is a formed tube assembly that feeds fuel to top of injectors Tops of injectors fit into formed cups in fuel rail When rail is fastened to manifold injectors are locked into place A small retaining clip provides a secondary lock Incorporated into fuel rail is a pressure relief test valve for testing operating pressure or relieving fuel system pressure for servicing Fuel supply line is attached to barbed end of fuel rail with an Oetiker hose clamp EFI engines have no carburetor so throttle function regulate incoming combustion airflow is incorporated in intake manifold assembly Manifold consists of a one piece aluminum casting which also provides mounting for fuel injectors throttle position sensor fuel rail air baffle idle speed screw and air cleaner assembly Idle speed is only adjustment that may be performed on EFI system Standard idle speed setting for EFI engines is 1500 RPM but certain applications might require a different setting Check equipmen
96. down line from pump Regulator is a sealed non serviceable assembly If it is faulty it must be separated from base holder assembly and replaced as follows 1 Shutengine off make sure engine is cool and disconnect negative battery cable 2 Depressurize fuel system through test valve in fuel rail 3 Access regulator assembly as required and clean any dirt or foreign material away from area 24 690 02 Rev E A Pressure Regulating B Pressure Regulating Spring Chamber Throttle Body Intake Manifold Assembly C Diaphragm D Valve Seat Throttle body intake manifold is serviced as an assembly with throttle shaft TPS throttle plates E Fuel Chamber F Outlet Port to fuel and idle speed adjusting screw installed Throttle rail shaft rotates on needle bearings non serviceable G Return Port to tank H Inlet Port capped with rubber seals to prevent air leaks A throttle shaft repair kit is available to replace shaft if worn or l Valve damaged Appropriate TPS Initialization Procedure must be performed after any throttle shaft service Idle Speed Adjustment RPM Adjustment Procedure 1 Make sure there are no fault codes present in ECU memory 2 Start engine and allow it to fully warm up and establish closed looped operation approximately 5 10 min KohlerEngines com 59 EFI SYSTEM BOSCH 3 Place throttle control in IDLE SLOW position and check idle speed with a tachometer Turn idle speed Screw in or o
97. e affecting crankshaft endplay KohlerEngines com 97 Disassembly Inspection and Service 1 Remove shoulder bolts securing fan if still attached and remove fan 2 Use a flywheel strap wrench or holding tool see Tools and Aids to hold flywheel and loosen screw securing flywheel to crankshaft 3 Remove screw and washer 4 Use a puller to remove flywheel from crankshaft 5 Remove woodruff key Inspection Inspect flywheel for cracks and flywheel keyway for damage Replace flywheel if it is cracked Replace flywheel crankshaft and key if flywheel key is sheared or keyway is damaged Inspect ring gear for cracks or damage Kohler does not provide ring gear as a serviceable part Replace flywheel if ring gear is damaged Remove Stator and Backing Plate ECV EFI Governor Gear Assembly Governor Shaft Press Depth Details 1 Remove screws securing backing plate Remove backing plate 2 Remove screws and stator Note position routing of stator lead Remove Oil Pan Assembly A Gear Shaft B 19 40 mm 0 7638 in C 34 0 mm 1 3386 in 33 5 mm 1 3189 in 1 Remove screws securing oil pan to crankcase 2 Locate splitting tabs cast into perimeter of closure plate Insert drive end of a 1 2 in breaker bar between splitting tab and crankcase and turn it to loosen seal Do not pry on sealing surfaces as this can cause leaks Inspection Inspect oil seal in oil pan and remove
98. e angle where maximum pressure occurs on outside diameters of valve face and seat Lapping Valves Reground or new valves must be lapped in to provide proper fit Use a hand valve grinder with a suction cup for final lapping Lightly coat valve face with a fine grade of grinding compound then rotate valve on its seat with grinder Continue grinding until a smooth surface is obtained on seat and on valve face Thoroughly clean cylinder head in soap and hot water to remove all traces of grinding compound After drying cylinder head apply a light coating of SAE 10 oil to prevent rusting Valve Stem Seal These engines use valve stem seals on intake and exhaust valves Always use a new seal when valves are removed from cylinder head Seals should also be replaced if deteriorated or damaged in any way Never reuse an old seal 24 690 02 Rev E Disassembly Inspection and Service Flywheel Components A Flywheel Fan B Flywheel C Stator D Backing Plate NOTE Always use a flywheel strap wrench or holding tool to hold flywheel when loosening or tightening flywheel screw Do not use any type of bar or wedge to hold flywheel Use of such tools could cause flywheel to become cracked or damaged NOTE Always use a flywheel puller to remove flywheel from crankshaft Do not strike crankshaft or flywheel as these parts could become cracked or damaged Striking puller or crankshaft can cause crank gear to mov
99. e guide and using a split ball gauge measure inside diameter of guide Then using an outside micrometer measure diameter of valve stem at several points on stem where it moves in valve guide Use largest stem diameter to calculate clearance by subtracting stem diameter from guide diameter If intake clearance exceeds 0 038 0 076 mm 0 0015 0 0030 in or exhaust clearance exceeds 0 050 0 088 mm 0 0020 0 0035 in determine whether valve stem or guide is responsible for excessive clearance Maximum I D wear on intake valve guide is 7 134 mm 0 2809 in while 7 159 mm 0 2819 in is maximum allowed on exhaust guide Guides are not removable but can be reamed 0 25 mm 0 010 in oversize Valves with 0 25 mm oversize stems must then be used If guides are within limits but valve stems are worn beyond limits install new valves Valve Seat Inserts Hardened steel alloy intake and exhaust valve seat inserts are press fitted into cylinder head Inserts are not replaceable but can be reconditioned if not too badly pitted or distorted If cracked or badly warped cylinder head should be replaced Recondition valve seat inserts following instructions provided with valve seat cutter being used Final cut should be made with an 89 cutter as specified for valve seat angle Cutting proper 45 valve face angle as specified and proper valve seat angle 44 5 half of full 89 angle will achieve desired 0 5 1 0 full cut interferenc
100. e odor Check condition of oil Drain oil into a container it should flow freely Check for metal chips and other foreign particles Sludge is a natural by product of combustion a small accumulation is normal Excessive sludge formation could indicate over rich fuel settings weak ignition overextended oil change interval or wrong weight or type of oil was used CLEANING ENGINE A WARNING 4 Cleaning Solvents can cause severe injury or death Use only in well ventilated areas away from ignition sources Carburetor cleaners and solvents are extremely flammable Follow cleaner manufacturer s warnings and instructions on its proper and safe use Never use gasoline as a cleaning agent After inspecting external condition of engine clean engine thoroughly before disassembly Clean individual components as engine is disassembled Only clean parts can be accurately inspected and gauged for wear or damage There are many commercially available cleaners that will quickly remove grease oil and grime from engine parts When such a cleaner is used follow manufacturer s instructions and safety precautions carefully Make sure all traces of cleaner are removed before engine is reassembled and placed into operation Even small amounts of these cleaners can quickly break down lubricating properties of engine oil 24 690 02 Rev E KohlerEngines com 19 Troubleshooting CRANKCASE VACUUM TEST
101. e reaches operating temperature an exhaust gas oxygen sensor provides feedback to ECU based upon amount of unused oxygen in exhaust indicating whether fuel mixture being delivered is rich or lean Based upon this feedback ECU further adjusts fuel input to re establish ideal air fuel ratio This operating mode is referred to as closed loop operation EFI system operates closed loop when all three of following conditions are met e Oil temperature is greater than 60 C 140 F e Oxygen sensor has warmed sufficiently to provide a signal minimum 400 C 752 F e Engine operation is at a steady state not starting warming up accelerating etc During closed loop operation ECU has ability to readjust temporary and learned adaptive controls providing compensation for changes in overall engine condition and operating environment so it will be able to maintain ideal air fuel ratio This system requires a minimum engine oil temperature greater than 80 C 176 F to properly adapt These adaptive values are maintained as long as ECU is not reset During certain operating periods such as cold starts warm up acceleration high load etc a richer air fuel ratio is required and system operates in an open loop mode In open loop operation oxygen sensor output is used to ensure engine is running rich and controlling adjustments are based on primary sensor signals and programmed maps only This system operates open loop whenever three co
102. e side is lower than level in open side pressure check for conditions in table below 4 Close pinch clamp before stopping engine Condition To test crankcase vacuum with vacuum pressure gauge 1 Remove dipstick or oil fill plug cap 2 Install adapter into oil fill dipstick tube opening upside down over end of a small diameter dipstick tube or directly into engine if a tube is not used Insert barbed gauge fitting into hole in stopper 3 Run engine and observe gauge reading Analog tester needle movement to left of 0 is a vacuum and movement to right indicates a pressure Digital tester depress test button on top of tester Crankcase vacuum should be a minimum of 10 2 cm 4 in of water If reading is below specification or if pressure is present check table below for possible causes and conclusions Conclusion Crankcase breather clogged or inoperative NOTE If breather is integral part of valve cover and cannot be serviced separately replace valve cover and recheck pressure Disassemble breather clean parts thoroughly check sealing surfaces for flatness reassemble and recheck pressure Seals and or gaskets leaking Loose or improperly torque fasteners Replace all worn or damaged seals and gaskets Make sure all fasteners are tightened securely Use appropriate torque valves and sequences when necessary Piston blow by or leaky valves confirm by inspecting components Restricted e
103. ect check mounting air gap toothed ring gear damage runout etc and flywheel key 6 Disconnect speed sensor connector from wiring harness It is connector with one heavy black lead Viewing connector as shown dual aligning rails on top test resistance between terminals indicated A reading of 750 1000 O should again be obtained 7 If resistance is incorrect remove screw securing sensor to mounting bracket and replace sensor a If resistance in step 5 was incorrect but resistance of sensor alone was correct test main harness circuits between sensor connector terminals and corresponding pin terminals in main connector Correct any observed problem reconnect sensor and perform step 5 again Speed Sensor Circuit Corresponds To F3 Metal Cased ECU or 10 Plastic Cased ECU In Main Connector B Dual Aligning Rails Corresponds To 21 Metal Cased ECU or 9 Plastic Cased D ECU In Main Connector Test Terminals 24 690 02 Rev E EFI SYSTEM BOSCH Throttle Position Sensor TPS Throttle Between Resistance bet dt Position Terminals Value O Continuity Closed 283 800 1200 Yes Closed 183 1800 3000 Yes Full 283 1800 3000 Yes Full 183 800 1200 Yes Any 1 amp 2 1600 2500 Yes A Throttle Valve Shaft B Resistor Track c Wiper Arm with D Electrical Wiper Connection TPS is a sealed non serviceable
104. el delivery maps ECU then knows how much fuel is required for starting at that temperature Intake Air Temperature IAT sensor is a thermally sensitive resistor that exhibits a change in electrical resistance with a change in its temperature When sensor is cold resistance of sensor is high As sensor warms up resistance drops and voltage signal increases From voltage signal ECU can determine temperature of intake air Purpose of an air temperature sensor is to help ECU calculate air density Higher air temperature less dense air becomes As air becomes less dense ECU knows that it needs to lessen fuel flow to achieve correct air fuel ratio If fuel ratio was not changed engine would become rich possibly losing power and consuming more fuel Oxygen sensor functions like a small battery generating a voltage signal to ECU based upon difference in oxygen content between exhaust gas and ambient air 24 690 02 Rev E Tip of sensor protruding into exhaust gas is hollow Outer portion of tip is surrounded by exhaust gas with inner portion exposed to ambient air When oxygen concentration on one side of tip is different than that of other side a voltage signal up to 1 0 volt is generated and sent to ECU Voltage signal tells ECU if engine is straying from ideal fuel mixture and ECU then adjusts injector pulse accordingly Oxygen sensor functions after being heated to a minimum of 400 C 752 F A heater inside sensor heats ele
105. el mixture Conclusion Temperature Sensor Related e Sensor wiring or connection Engine Wiring Harness Related 24 Pin MSE 1 0 Plastic Cased ECU e Pin circuits 4 6 and or 4A damaged wires connectors or routed near noisy signal coils alternator etc e ECU to harness connection problem Engine Wiring Harness Related 32 Pin MSE 1 1 Plastic Cased ECU e Pin circuits 4 6 and or 4A damaged wires connectors or routed near noisy signal coils alternator etc e ECU to harness connection problem System Related e Engine is operating above 176 C 350 F temperature sensor limit Code 43 and 44 32 Pin MSE 1 1 Plastic Cased Component Injector 1 circuit open shorted to ground or shorted to battery Fault Injector 1 is not functioning because circuit is open shorted to ground or shorted to battery Condition Engine will run very poorly with only one cylinder functioning Conclusion Injector Related e Injector coil shorted or opened Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin 14 to injector pin 2 ECU pin 28 to fuel pump relay pin 86 Note after key off then key on code 56 would be set also Fuel pump relay pin 87 to injector pin 1 e Open main fuse F1 Fuel Pump Relay Related e Bad fuel pump relay Primary side functional but pin 30 to pin 87 remains open Primary side pin 85 to pin 86 is either ope
106. elay terminal 87 and pin 16 in main connector Then check resistance between relay terminal 87and pin 17 Resistance should be 4 15 Q for each circuit 32 Pin MSE 1 1 Plastic Cased ECU Check resistance between relay terminal 87 and pin 14 in main connector Then check resistance between relay terminal 87 and pin 15 Resistance should be 4 15 O for each circuit Check all electrical connections connectors and wiring harness leads if resistance is incorrect Injector leakage is very unlikely but in those rare instances it can be internal past tip of valve needle or external weeping around injector body Loss of system pressure from leakage can cause hot restart problems and longer cranking times To check for leakage it will be necessary to loosen or remove blower housing which may involve removing engine from unit 24 690 02 Rev E EFI SYSTEM BOSCH Injector Inspection Points Check for Leaks 10 11 Engine must be cool Depressurize fuel system through test valve in fuel rail Disconnect spark plug leads from spark plugs Remove air cleaner outer cover inner wing nut element cover and air cleaner element precleaner Service air cleaner components as required Remove screws securing air cleaner base to throttle body manifold Remove air cleaner base to permit access to injectors Check condition of air cleaner base gasket replace if necessary Remove flywheel screen if i
107. em pressure a If pressure is too high and regulator is outside tank just down line from pump check that return line from regulator to tank is not kinked or blocked If return line is good replace regulator see Regulator on page 24 690 02 Rev E b If pressure is too low install in line T between pump and regulator and retest pressure at that point If it is too low there also replace fuel pump 3 If pump did not activate step 2 disconnect plug from fuel pump Connect a DC voltmeter across terminals in plug turn on key switch and observe if a minimum of 7 volts is present If voltage is between 7 and 14 turn key switch off and connect an ohmmeter between terminals on pump to check for continuity a If there was no continuity between pump terminals replace fuel pump b If voltage was below 7 test wiring harness and relay as covered in Electrical Relay 4 If voltage at plug was good and there was continuity across pump terminals reconnect plug to pump making sure you have a good connection Turn on key switch and listen for pump to activate a If pump starts repeat steps 1 and 2 to verify correct pressure b If pump still does not operate replace it Fuel Pressure Regulator Details EFI SYSTEM BOSCH 4 External Regulator a Remove screws securing mounting bracket to regulator housing Remove O Ring and pull regulator out of housing b Remove snap ring and remove regulator
108. em 4 or 5 turns into flywheel 3 Install a spring washer on each stud with concave side down toward cooling fan 4 Install a spacer on each stud with stepped end down Smaller diameter should extend through spring washer and fan so tip is resting on flywheel and shoulder is resting on spring washer 5 Install support ring on studs so it is resting on spacers Then install metal screen on top of support ring 24 690 02 Rev E 6 T Reassembly Install a plain washers on each of screws Apply Loctite 2429 to screw threads Carefully remove studs and replace with screws Torque screws to 9 9 N m 88 in Ib Repeat procedure for other studs and screws Install Plastic Debris Screen Place plastic debris screen on fan and secure with four screws Torque screws to 4 0 N m 35 in Ib Install Oil Separator and Hardware 1 Ensure rubber oil separator grommet is in good condition Insert rubber grommet into valve cover Push oil separator into rubber grommet in valve cover Secure oil separator to blower housing placing spacer and oil separator bracket against blower housing and securing with strap and screws Torgue screws to 2 3 N m 20 in Ib Install Electric Starter Motor and ECU Bracket ECV EFI 1 Install electric starter motor using screws Position ECU bracket 2 Torque screws to 16 0 N m 142 in Ib 3 Connect leads to solenoid 4 Install dipstick tube and align mounting
109. em with temperature sensor it can be tested as follows 1 2 Remove oil temperature sensor from adapter housing and cap or block adapter hole Wipe sensor clean and allow it to reach room temperature 20 C 68 F Unplug main harness connector from ECU With sensor connected check oil temperature sensor circuit resistance Value should be 2375 2625 O See chart on pages 24 Pin MSE 1 0 Plastic Cased ECU Check between 6 and 4 pin terminals 32 Pin MSE 1 1 Plastic Cased ECU Check between 6 and 4 pin terminals Unplug sensor connector and check sensor resistance separately Resistance value should again be 2375 2625 O a If resistance is out of specifications replace temperature sensor b Ifitis within specifications proceed to Step 6 Check temperature sensor circuits input ground from main harness connector to corresponding terminal in sensor plug for continuity damage etc 24 Pin MSE 1 0 Plastic Cased ECU Pin circuits 6 and 4 24 690 02 Rev E 32 Pin MSE 1 1 Plastic Cased ECU Pin circuits 6 and 4 Cutaway of Oxygen Sensor A Connection Cable B Disc Spring Ceramic Support C Tube D Protective Sleeve E Contact Element F Sensor Housing Active Ceramic G Sansa H Protective Tube NOTE All tests should be conducted with a good quality high impedance digital VOA meter for accurate results Like
110. emble engine Use new O Rings any time an injector is removed new replacement injectors include new O Rings Lubricate O Rings lightly with oil Torque fuel rail and blower housing mounting screws to 3 9 N m 35 in Ib and intake manifold and air cleaner mounting screws to 9 9 N m 88 in Ib Injector problems due to dirt or clogging are generally unlikely due to design of injectors high fuel pressure and detergent additives in gasoline Symptoms that could be caused by dirty clogged injectors include rough idle hesitation stumble during acceleration or triggering of fault codes related to fuel delivery Injector clogging is usually caused by a buildup of deposits on director plate restricting flow of fuel resulting in a poor spray pattern Some contributing factors to injector clogging include higher than normal operating temperatures short operating intervals and dirty incorrect or poor quality fuel Cleaning of clogged injectors is not recommended they should be replaced Additives and higher grades of fuel can be used as a preventative measure if clogging has been a problem NOTE Do not ground coils with ignition ON as they may overheat or spark Testing 1 Disconnect main harness connector from ECU 24 Pin MSE 1 0 Plastic Cased ECU Locate pins 22 and 23 in 24 pin connector See page 32 Pin MSE 1 1 Plastic Cased ECU Locate pins 30 and 31 in 32 pin connector See page 2 Disconnect connector from rel
111. en sensor disconnected and engine not running disconnect main harness connector from ECU and set meter to Rx1 scale Check circuit continuity as follows 24 Pin MSE 1 0 Plastic Cased ECU Check for continuity from pin 15 of ECU connector see page to shell of oxygen sensor and from pin 11 to sensor connector terminal of main harness Both tests should indicate continuity 32 Pin MSE 1 1 Plastic Cased ECU Check for continuity from pin 19 of ECU connector see page to shell of oxygen sensor and from pin 20 to sensor terminal of main harness Both tests should indicate continuity a If there is no continuity displayed in either of tests check harness circuit for breaks or damage and connections for poor contact moisture or corrosion If no continuity was found in first test also check for a poor broken ground path back through exhaust system engine and mounting sensor is grounded through its shell 24 690 02 Rev E KohlerEngines com 55 EFI SYSTEM BOSCH 6 b If continuity is indicated go to step 6 With key switch in ON RUN position using a high impedance voltmeter check voltage from wiring harness oxygen sensor connector to engine ground location Look for a steady voltage from 350 550 mv 0 35 0 55 v a If voltage reading is not as specified move black voltmeter lead to negative post of battery to be certain of a good ground If voltage is still not correct ECU is probably bad b If
112. ency Fuel delivery is based upon oxygen sensor and five mapped values only Rich running black smoke will occur until closed loop operation is initiated A stumble or misfire on hard acceleration and or erratic operation may be exhibited 70 KohlerEngines com 24 690 02 Rev E Conclusion Engine Speed Sensor Related e Sensor connector or wiring e Sensor loose or air gap incorrect Speed Sensor Wheel Related e Damaged teeth e Gap section not registering Engine Wiring Harness Related Pin s 9 and or 10 for 24 Pin MSE 1 0 Plastic Cased ECU Pin s 9 and or 10 for 32 Pin MSE 1 1 Plastic Cased ECU ECU Harness Related e ECU to harness connection problem EFI SYSTEM BOSCH Code 31 Component Fuel Mixture or Oxygen Sensor Fault System too lean Oxygen sensor not sending expected voltage to ECU Code 32 Component Oxygen Sensor Fault No change in sensor output signal Condition Open loop operation only may cause a drop in system performance and fuel efficiency Conclusion Engine Wiring Harness Related e Pin circuit wiring or connectors Pin 11 for 24 Pin MSE 1 0 Plastic Cased ECU Pin 20 for 32 Pin MSE 1 1 Plastic Cased ECU Oxygen Sensor Related e Sensor connector or wiring problem e Sensor contaminated or damaged e Sensor below minimum operating temperature 375 C 709 F e Poor ground path f
113. ensor Related e Sensor connector or wiring e Sensor loose or incorrect air gap e Flywheel key sheared Speed Sensor Ring Gear Related e Damaged teeth e Varying gap gear loose out of alignment Engine Wiring Harness Related 24 Pin MSE 1 0 Plastic Cased ECU e Pin circuits 9 and or 10 wiring or connectors e Shielding for pin circuits 9 and or 10 damaged or not properly grounded e Poor or improper grounds in system battery ECU oxygen sensor shielding fuel pump ignition output e Pin circuits 9 and or 10 routed near noisy electrical signals coils spark plug lead plug connector Engine Wiring Harness Related 32 Pin MSE 1 1 Plastic Cased ECU e Pin circuits 9 and or 10 wiring or connectors e Shielding for pin circuits 9 and or 10 damaged or not properly grounded e Poor or improper grounds in system battery ECU oxygen sensor shielding fuel pump ignition output e Pin circuits 9 and or 10 routed near noisy electrical signals coils spark plug lead plug connector ECU Harness Related e ECU to harness connection problem Ignition System Related e Non resistor spark plug s used Conclusion TPS Sensor Related e Sensor connector or wiring e Sensor output affected or disrupted by dirt grease oil wear or breather tube position must be to side opposite TPS e Sensor loose on throttle body manifold Throttle Body Related e Throttle shaft or bearings worn
114. er Use a strong detergent capable of breaking down machining oil while maintaining a good level of suds If suds break down during cleaning discard dirty water and start again with more hot water and detergent Following scrubbing rinse cylinder with very hot clear water dry it completely and apply a light coating of engine oil to prevent rusting Measuring Piston to Bore Clearance Piston Detail wll E A 6 mm 0 24 in NOTE Do not use a feeler gauge to measure piston to bore clearance it will yield inaccurate measurements Always use a micrometer Before installing piston into cylinder bore it is necessary clearance be accurately checked This step is often overlooked and if clearances are not within specifications engine failure will usually result Use these following procedures to accurately measure piston to bore clearance 1 Use a micrometer and measure diameter of piston 6 mm 0 24 in above bottom of piston skirt and perpendicular to piston pin 2 Use an inside micrometer telescoping gauge or bore gauge and measure cylinder bore Take measurement approximately 63 5 mm 2 5 in below top of bore and perpendicular to piston pin 3 Piston to bore clearance is difference between bore diameter and piston diameter step 2 minus step 1 KohlerEngines com 103 Reassembly Crankcase Components A Oil Pan Seal B Oil Pan C
115. ery e Low output charging system e Poor magnet in flywheel e Bad or missing fuse Code 0563 Component System Voltage Fault System Voltage High Condition Faulty voltage regulator or shorted connection Conclusion Faulty Rectifier Regulator Bad Stator Bad Battery Code 61 Component End of Code Transmission 24 690 02 Rev E EFI SYSTEM ECV Troubleshooting Flow Chart Following flow chart provides an alternative method of troubleshooting EFI system Chart will enable you to review entire system in about 10 15 minutes Using chart accompanying diagnostic aids listed chart and any signaled fault codes you should be able to quickly locate any problems within system Flow Chart Diagnostic Aids Diagnostic Aid 1 SYSTEM POWER MIL does not illuminate when key is turned ON NOTE MIL is installed by vehicle OEM Twelve volt supply to bulb will be part of vehicle wire harness Kohler key switch model will have MIL on engine with 12V supply to bulb Conclusion e Battery e Main system fuse e MIL light bulb burned out e MIL electrical circuit problem Pin circuits Grey 3 e gnition switch e Permanent ECU power circuit problem Pin circuit Black 18 e Switched ECU power circuit problem Pin circuit Black 15 e ECU grounds e ECU Diagnostic Aid 2 FAULT CODES Refer to Diagnostic Fault Code Summary Diagnostic Aid 3 RUN ON MIL remains ON while engine is running Condition NOTE
116. es input signals to programmed maps in its memory to determine appropriate fuel and spark requirements for immediate operating conditions ECU then sends output signals to set injector duration and ignition timing ECU compares input signals to programmed maps in its memory to determine appropriate fuel and spark requirements for immediate operating conditions ECU then sends output signals to set injector duration and ignition timing ECU continually performs a diagnostic check of itself each of sensors and system performance If a fault is detected ECU can turn on a Malfunction Indicator Light MIL if equipped on equipment control panel store fault code in its fault memory and go into a default operating mode Depending on significance or severity of fault normal operation may continue A technician can access stored fault code using a blink code diagnosis flashed out through MIL An optional computer software diagnostic program is also available refer to Tools and Aids KohlerEngines com 49 EFI SYSTEM BOSCH ECU requires a minimum of 7 0 volts to operate Adaptive memory in ECU is operational whenever required voltage is present however adapted values are lost if power supply is disrupted for any reason ECU will relearn adapted values if engine is operated for 10 15 minutes at varying speeds and loads after oil temperature exceeds 55 C 130 F To prevent engine over speed and possible failure a rev limiting
117. es which at first may seem too obvious to be considered For example a starting problem could be caused by an empty fuel tank Some general common causes of engine troubles are listed below and vary by engine specification Use these to locate causing factors Engine Cranks But Will Not Start Engine Will Not Crank e Battery connected backwards e Blown fuse e Carburetor solenoid malfunction e Choke not closing e Clogged fuel line or fuel filter e Diode in wiring harness failed in open circuit mode e DSAI or DSAM malfunction e Empty fuel tank e Faulty electronic control unit e Faulty ignition coil s e Faulty spark plug s e Fuel pump malfunction vacuum hose clogged or leaking e Fuel shut off valve closed e Ignition module s faulty or improperly gapped e Insufficient voltage to electronic control unit e Interlock switch is engaged or faulty e Key switch or kill switch in OFF position e Low oil level e Quality of fuel dirt water stale mixture e SMART SPARK malfunction e Spark plug lead s disconnected Engine Starts But Does Not Keep Running e Battery is discharged e Faulty electric starter or solenoid e Faulty key switch or ignition switch e Interlock switch is engaged or faulty e Loose wires or connections that intermittently ground ignition kill circuit e Pawls not engaging in drive cup e Seized internal engine components Engine Runs But Misses e Carbu
118. expander and then rails Make sure ends of expander are not overlapped 2 Middle Compression Ring Center Groove Install center ring using a piston ring installation tool Make sure identification mark is up or dye colored stripe if contained is left of end gap 3 Top Compression Ring Top Groove Install top ring using a piston ring expender Make sure identification mark is up or dye colored stripe if contained is left of end gap Connecting Rods Offset stepped cap connecting rods are used in all these engines Inspection and Service Check bearing area big end for excessive wear Score marks running and side clearances refer to Specifications Replace rod and cap if scored or excessively worn Service replacement connecting rods are available in STD crankpin size and 0 25 mm 0 010 in undersize 0 25 mm 0 010 in undersized rod can be identified by drilled hole located in lower end of rod shank Always refer to appropriate parts information to ensure correct replacements are used KohlerEngines com 101 Disassembly Inspection and Service Remove Crankshaft Carefully pull crankshaft from crankcase Inspection and Service Crankshaft Components and Details Flat Washer Crankshaft A Self Tapping Screw B C Plug D Fillet Must Blend Smoothly with Bearing Journal Surface High Point from Fillet Intersections o n m 45 Minimum
119. filter plugged e Fuel supply line plugged e Lift fuel pump insufficient fuel supply e Fuel pump lift or module internally plugged Low Fuel Pressure Condition e Pressure regulator not functioning properly inside fuel pump module Diagnostic Aid 9 BASIC ENGINE cranks but will not run Condition e Refer to basic engine troubleshooting charts within Troubleshooting Electronic Fuel Injection System ECVI EFI and Electrical Systems 46 KohlerEngines com 24 690 02 Rev E EFI SYSTEM ECV EFI Diagnostic Flow Diagram START OF TEST PROCEED TO START OF TEST FOR RETEST MALFUNCTION INDICATOR LIGHT NO REFER TO DIAGNOSTIC AID 1 SYSTEM POWER REFER TO DIAGNOSTIC FAULT CODE SUMMARY CLEAR CODES REFER TO DIAGNOSTIC AID 3 RUN ON ARE FAULT CODES PRESENT DOES ENGINE START NO YES OPERATE AT VARIQUS SPEED LOAD CONDITIONS CRANK ENGINE DOES MIL GO OFF REFER TO DIAGNOSTIC FAULT CODE SUMMARY CLEAR CODES ARE FAULT CODES PRESENT NO NO END OF TEST REFER TO DIAGNOSTIC AID 4 CRANKSHAFT POSITION SENSOR REFER TO DIAGNOSTIC AID 5 FUEL NO REFER TO DIAGNOSTIC AID 6 IGNITION SYSTEM YES KEY OFF AND KEY ON LISTEN FOR FUEL PUMP DOES FUEL PUMP CYCLI N OFF AFTER 1 2 ECONDS YES NO WHILE CRANKING CHECK IGNITION SYSTEM PROCEED TO START OF TEST FOR RETEST YES WHILE CRANKING CHECK INJECTOR FUEL DELIVERY WET SPARK
120. filter side disconnect Grey connector from ECU and test between Grey pins 10 and 17 Wiring and coil primary circuits are OK if readings are 0 5 0 8 O 2 If reading s are not within specified range check and clean connections and retest 3 If reading s are still not within specified range test coils separately from main harness as follows a Remove screw retaining coil to housing and disconnect primary leads connector 36 KohlerEngines com b Connect an ohmmeter set on Rx1 scale to primary terminals of coil Primary resistance should be 0 5 0 8 O c Connect an ohmmeter set on Rx10K scale between spark plug boot terminal and B primary terminal Secondary resistance should be 6400 7800 O d If secondary resistance is not within specified range coil is faulty and needs to be replaced FUEL COMPONENTS A WARNING Explosive Fuel can cause fires and severe burns gt Fuel system ALWAYS remains under HIGH PRESSURE Wrap a shop towel completely around fuel pump module connector Press release button s and slowly pull connector away from fuel pump module allowing shop towel to absorb any residual fuel in high pressure fuel line Any spilled fuel must be completely wiped up immediately Fuel Pump Fuel pump module is not serviceable and must be replaced if determined to be faulty If a fuel pump problem is suspected make certain pump is being activated all electrical connections are properly secu
121. fuel pump then remove fuel pump with lines attached KohlerEngines com 1 2 3 Remove screws securing fuel pump module Lift grey locking tab and squeeze to disconnect electrical connector Disconnect vent hose from top of fuel pump module Wrap a shop towel completely around high pressure fuel line connector Press release button s and slowly pull connector away from fuel pump module allowing shop towel to absorb any residual fuel in high pressure fuel line Any spilled fuel must be completely wiped up immediately Using a side cutter or similar tool cut Oetiker clamp to remove inlet fuel line A new Oetiker clamp will need to be used for reassembly 24 690 02 Rev E 7 Remove screws securing fuel pump module baffle which pump was mounted to Remove Throttle Body 1 Disconnect intake air temperature sensor from throttle body Disconnect breather tube from throttle body Disconnect throttle position sensor connector Disconnect vent hose from throttle body If equipped remove screws securing heavy duty air cleaner bracket take off bracket and slide throttle body off intake manifold ECU ECV ak oh Remove Electronic Control Unit ECU Electronic Control B ECU Bracket Unit ECU C Starter 1 Remove screws securing ECU to bracket 2 Disconnect Black and Grey electrical connectors from ECU Remove Electronic Control Unit Bracket and Electric
122. ge of each stone positioned even with lowest edge of bore start drill and honing process Move hone up and down while resizing to prevent formation of cutting ridges Check size frequently 3 When bore is within 0 064 mm 0 0025 in of desired size remove coarse stones and replace them with burnishing stones Continue with burnishing stones until bore is within 0 013 mm 0 0005 in of desired size and then use finish stones 220 280 grit and polish bore to its final size A crosshatch should be observed if honing is done correctly Crosshatch should intersect at approximately 23 33 off horizontal Too flat an angle could cause rings to skip and wear excessively and too steep an angle will result in high oil consumption 4 After resizing check bore for roundness taper and size Use an inside micrometer telescoping gauge or bore gauge to take measurements These measurements should be taken at 3 locations in cylinder at top middle and bottom Two measurements should be taken perpendicular to each other at each location 24 690 02 Rev E Disassembly Inspection and Service Clean Cylinder Bore After Honing Proper cleaning of cylinder walls following boring and or honing is very critical to a successful overhaul Machining grit left in cylinder bore can destroy an engine in less than 1 hour of operation after a rebuild Final cleaning operation should always be a thorough scrubbing with a brush and hot soapy wat
123. gh fuel line and in line fuel filter A fuel pressure regulator maintains a system operating pressure of 39 psi and returns any excess fuel to tank At engine fuel is fed through fuel rail and into injectors which inject it into intake ports ECU controls amount of fuel by varying length of time that injectors are ON This can range from 1 5 8 0 milliseconds depending on fuel requirements Controlled injection of fuel occurs each crankshaft revolution or twice for each 4 stroke cycle One half total amount of fuel needed for one firing of a cylinder is injected during each injection When intake valve opens fuel air mixture is drawn into combustion chamber ignited and burned ECU controls amount of fuel being injected and ignition timing by monitoring primary sensor signals for engine temperature speed RPM and throttle position load 24 690 02 Rev E EFI SYSTEM BOSCH These primary signals are compared to preprogrammed maps in ECU computer chip and ECU adjusts fuel delivery to match mapped values After engine reaches operating temperature an exhaust gas oxygen sensor provides feedback to ECU based upon amount of unused oxygen in exhaust indicating whether fuel mixture being delivered is rich or lean Based upon this feedback ECU further adjusts fuel input to re establish ideal air fuel ratio This operating mode is referred to as closed loop operation EFI system operates closed loop when all three of following conditio
124. harness 2 Install remaining muffler support hardware screws and nuts and torque to 9 9 N m 88 in Ib 3 Install nuts to exhaust studs Torque nuts to 27 8 N m 246 in Ib 24 690 02 Rev E Reassembly Install Oil Cooler if equipped 1 Secure adapter to oil pan with oil filter nipple Torque oil filter nipple to 28 5 N m 21 ft Ib 2 Verify all fuel and vent hoses are routed properly and not pinched Install screws to secure oil cooler to blower housing Torque top screw to 2 8 N m 25 in Ib and lower screw to 2 3 N m 20 in Ib Install Oil Filter and Fill Crankcase with Oil NOTE If testing oil pressure after completing reassembly install oil pressure adapter instead of oil filter Prefill a new oil filter following instructions 2 Place new filter in shallow pan with open end up Fill with new oil until oil reaches bottom of threads Allow 2 minutes for oil to be absorbed by filter material 3 Apply a thin film of clean oil to rubber gasket on oil filter 4 Refer to instructions on oil filter for proper installation 5 Fill crankcase with new oil Level should be at top of indicator on dipstick 6 Reinstall oil fill cap dipstick and tighten securely Connect Spark Plug Leads 1 Connect leads to spark plugs Prepare Engine for Operation ECV EFI NOTE If ECU throttle body TPS or fuel pump module were replaced an ECU Reset and TPS Learn is required Refer to Ele
125. hin system Flow Chart Diagnostic Aids Diagnostic Aid 1 system power MIL does not illuminate when key is turned ON NOTE MIL in Metal Cased ECU systems is an LED MIL in Plastic Cased ECU systems must be a 1 4 watt incandescent lamp Possible causes e Battery e Main system fuse e MIL light bulb burned out e MIL electrical circuit problem 24 Pin MSE 1 0 Plastic Cased ECU Pin circuits 19 and 84 32 Pin MSE 1 1 Plastic Cased ECU Pin circuits 29 and 84 24 690 02 Rev E e gnition switch e Permanent ECU power circuit problem 24 Pin MSE 1 0 Plastic Cased ECU Pin circuit 1 32 Pin MSE 1 1 Plastic Cased ECU Pin circuit 1 e Switched ECU power circuit problem 24 Pin MSE 1 0 Plastic Cased ECU Pin circuit 2 32 Pin MSE 1 1 Plastic Cased ECU Pin circuit 2 e ECU grounds e ECU Diagnostic Aid 2 FAULT CODES Refer to detailed fault code listing before flow chart and servicing information for respective components e Code 21 Engine Speed Synchronization e Code 22 Throttle Position Sensor TPS e Code 23 Engine Control Unit ECU e Code 31 Oxygen Sensor e Code 32 Oxygen Sensor e Code 33 Fuel System temporary adaptation factor e Code 34 Fuel System permanent adaptation factor e Code 42 Engine Oil Temperature Sensor e Code 43 TPS Auto Learn Initialization Function Below Min Limit 32 Pin MSE 1 1 Plastic Cased ECU only e Code 44 TPS Auto Learn Initia
126. icient compensation Conclusion Oxygen Sensor Related e Sensor connector or wiring problem e Sensor contaminated or damaged e Exhaust leak e Poor ground path e Pin circuit wiring or connectors Pin 11 for 24 Pin MSE 1 0 Plastic Cased ECU Pin 20 for 32 Pin MSE 1 1 Plastic Cased ECU TPS Sensor Related e Throttle plate position incorrect during Initialization procedure e TPS problem or malfunction Engine Wiring Harness Related e Difference in voltage between sensed voltage pin circuit 17 for metal cased ECU pin circuit 2 for plastic cased ECU and actual injector voltage circuit 45 45A e Problem in wiring harness e ECU to harness connection problem Systems Related e Ignition spark plug plug wire ignition coil e Fuel fuel type quality injector fuel pressure fuel pump e Combustion air air cleaner dirty restricted intake leak throttle bores e Base engine problem rings valves e Exhaust system leak muffler flange oxygen sensor mounting boss etc e Fuel in crankcase oil e Altitude e Blocked or restricted fuel return circuit to tank 72 KohlerEngines com 24 690 02 Rev E EFI SYSTEM BOSCH Code 51 32 Pin MSE 1 1 Plastic Cased ECU only Code 42 Component Engine Oil Temperature Sensor Fault Not sending proper signal to ECU Condition Engine may be hard to start because ECU can t determine correct fu
127. il filter for proper installation 6 Fill crankcase with new oil Level should be at top of indicator on dipstick 24 690 02 Rev E 7 Reinstall oil fill cap dipstick and tighten securely 8 Start engine check for oil leaks Stop engine correct leaks Recheck oil level 9 Dispose of used oil and filter in accordance with local ordinances OIL COOLER if equipped 1 Clean fins with a brush or compressed air 2 Remove screws securing oil cooler and tilt to clean back side 3 Reinstall oil cooler and torque to 2 2 N m 20 in Ib OIL SENTRY if equipped This switch is designed to prevent engine from starting in a low oil or no oil condition Oil Sentry may not shut down a running engine before damage occurs In some applications this switch may activate a warning signal Read your equipment manuals for more information Oil Sentry pressure switch is installed in breather cover On engines not equipped with Oil Sentry installation hole is sealed with a 1 8 27 N P T F pipe plug Installation 1 Apply pipe sealant with Teflon Loctite PST9 5927 Thread Sealant or equivalent to threads of switch 2 Install switch into tapped hole in breather cover 3 Torque switch to 4 5 N m 40 in Ib 24 690 02 Rev E Lubrication System Testing Compressed air a pressure regulator pressure gauge and a continuity tester are required to test switch ECV Models Normally Closed Switch 1 Connect
128. ircuit 30 e ECU grounds e ECU KohlerEngines com 75 EFI SYSTEM BOSCH Diagnostic Aid 8 FUEL SYSTEM ELECTRICAL no fuel delivery Possible causes e No fuel e Air in fuel rail e Fuel valve shut off e Fuel filter line plugged e Injector circuit s 24 Pin MSE 1 0 Plastic Cased ECU Circuits 16 17 45 and 45A 32 Pin MSE 1 1 Plastic Cased ECU Circuits 14 15 and 45 e Injector e ECU grounds e ECU Diagnostic Aid 9 FUEL SYSTEM fuel pressure Possible causes for low fuel system pressure e Low fuel e Fuel filter plugged e Fuel supply line plugged e Fuel pump Possible causes for high fuel system pressure e Pressure regulator e Fuel return line plugged or restricted Diagnostic Aid 10 BASIC ENGINE cranks but will not run Possible causes e Refer to basic engine troubleshooting charts within Troubleshooting Electronic Fuel Injection System ECV EFI and Electrical Systems 76 KohlerEngines com 24 690 02 Rev E EFI SYSTEM BOSCH Bosch EFI Diagnostic Flow Diagram Proceed to Start of Test for retest MALFUNCTION INDICATOR REFER TO DIAGNOSTIC AID 1 LIGHTS ON FAULT CODES ARE FAULT CODES PRESENT REFER TO DIAGNOSTIC AID 2 FAULT CODES CLEAR CODES DOES ENGINE START Yes REFER TO DIAGNOSTIC AID 3 RUN ON OPERATE AT VARIOUS SPEED LOAD CONDITIONS ARE FAULT CODES PRESENT No END OF TEST REFER TO DIAGNOSTIC AID 4 Yes
129. it if it is worn or damaged Refer to Install Oll Pan Oil Seal in Reassembly for new oil seal installation Inspect main bearing surface for wear or damage refer to Specifications Replace oil pan assembly if required 98 KohlerEngines com Governor gear assembly is located inside oil pan If service is required continue with Inspection Disassembly and Reassembly Inspection Inspect governor gear teeth Replace gear if it is worn chipped or if any teeth are missing Inspect governor weights They should move freely in governor gear Disassembly NOTE Governor gear is held onto shaft by small molded tabs in gear When gear is removed from shaft these tabs are destroyed and gear must be replaced Therefore remove gear only if absolutely necessary Governor gear must be replaced once it is removed from oil pan 1 Remove regulating pin and governor gear assembly 2 Remove locking tab thrust washer located under governor gear assembly 3 Carefully inspect governor gear shaft and replace it only if it is damaged After removing damaged shaft press or lightly tap replacement shaft into oil pan to depth shown Reassembly 1 Install locking tab thrust washer on governor gear shaft with tab down 2 Position regulating pin within governor gear flyweight assembly and slide both onto governor shaft 24 690 02 Rev E Oil Pump Assembly Disassembly Inspection and Service Crankcase Components Oil Pump T
130. key OFF for at least 10 seconds between tests to allow ECU to go to sleep and reawake Repeat test at other connector a If flashing occurs use an ohmmeter Rx1 scale and check resistance of each injector across two terminals Proper resistance is 11 13 O If injector resistance is correct check whether connector and injector terminals are making a good connection If resistance is not correct replace injector Check all electrical connections connectors and wiring harness leads if resistance is incorrect Injector leakage is very unlikely but in those rare instances it can be internal past tip of valve needle or external weeping around injector O rings Loss of System pressure from leakage can cause hot restart problems and longer cranking times To check for leakage it will be necessary to loosen or remove blower housing which may involve removing engine from unit Refer to Disassembly for removal of injector 1 Remove manifold mounting bolts and separate throttle body manifold from engine leaving TPS high pressure fuel line injectors and fuel line connections intact Discard old gaskets 2 Position manifold assembly over an appropriate container to capture fuel and turn key switch ON to activate fuel pump and pressurize system Do not turn switch to START position NOTE Fuel pump module pins are coated with a thin layer of electrical grease to prevent fretting and corrosion Do not attempt to remove electrical g
131. l Temperature Sensor Circuit Low Voltage 0118 Coolant Oil Temperature Sensor Circuit High Voltage or Open 0122 Throttle Position Sensor Circuit Low Voltage or Open 0123 Throttle Position Sensor Circuit High Voltage 0131 Oxygen Sensor 1 Circuit Low Voltage or Open 0132 Oxygen Sensor 1 Circuit High Voltage 0171 Maximum Adaptation Limit Exceeded 0172 Minimum Adaptation Limit Exceeded 0174 Lean Fuel Condition at High Load Open Loop 0201 Injector 1 Circuit Malfunction 0202 Injector 2 Circuit Malfunction 24 690 02 Rev E KohlerEngines com 39 EFI SYSTEM ECV 0230 Fuel Pump Module Circuit Low Voltage or Open 0232 Fuel Pump Module Circuit High Voltage 0336 Crankshaft Position Sensor Noisy Signal 0337 Crankshaft Position Sensor No Signal 0351 Cylinder 1 Ignition Coil Malfunction 0352 Cylinder 2 Ignition Coil Malfunction 0562 System Voltage Low 0563 System Voltage High 61 End of Code Transmission ECU continuously monitors engine operation against preset performance limits If operation is outside limits ECU activates MIL if equipped and stores a diagnostic code in its fault memory If component or system returns to proper function ECU will turn off MIL If MIL stays illuminated it warns customer a fault is currently happening and dealer service is required Upon receipt dealer technician can access fault code s to help determine what portion of system is malfunctioning Codes are accessed through ke
132. l electronic fuel injection EFI system and related components include e Fuel tank and valve e Fuel pump e Fuel filter e Fuel rail e Fuel line s e Fuel injectors e Fuel pressure regulator e Throttle body intake manifold e Electronic control unit ECU e Ignition coils e Engine oil temperature sensor e Throttle position sensor TPS e Speed sensor e Crankshaft position sensor e Oxygen sensor e Wire harness assembly amp affiliated wiring e Malfunction indicator light MIL e Intake air temperature sensor FUEL RECOMMENDATIONS Refer to Maintenance FUEL LINE Low permeation fuel line must be installed on all Kohler Co engines to maintain EPA and CARB regulatory compliance OPERATION NOTE When performing voltage or continuity tests avoid putting excessive pressure on or against connector pins Flat pin probes are recommended for testing to avoid spreading or bending terminals EFI system is designed to provide peak engine performance with optimum fuel efficiency and lowest possible emissions Ignition and injection functions are electronically controlled monitored and continually corrected during operation to maintain ideal air fuel ratio Central component of system is Engine Control Unit ECU which manages system operation determining best combination of fuel mixture and ignition timing for current operating conditions An electric fuel pump is used to move fuel from tank throu
133. l shorted or opened Conclusion Crankshaft Position Sensor Related e Sensor connector or wiring Engine Wiring Harness Related e Sensor loose or air gap incorrect e Broken or shorted wire in harness ECU pin Black 6 Crankshaft Position Sensor Wheel e Wiring from Ignition Related e Damaged teeth ECU Related e Gap section not registering e Circuit controlling injector 2 damaged Engine Wiring Harness Related Code 0230 e Pin circuit wiring or connectors Component Fuel Pump ECU pin Black 4 and Black 13 Fault Circuit Low Voltage or Open e ECU to harness connection problem Condition Shorted or open connection Ignition System Related Conclusion Fuel Pump Related e Non resistor spark plug s used e Fuel pump module open or shorted e Faulty or disconnected ignition coil or internally secondary lead Engine Wiring Harness related Code 0337 e Broken or shorted wire in harness Component Crankshaft Position Sensor EGU pit Blacks or Grey TES Fault Crankshaft Position Sensor No Signal ECU Related Condition Air gap incorrect loose sensor open or e ECU is damaged shorted connection or faulty sensor Conclusion Crankshaft Position Sensor Related Code 0232 e Sensor connector or wiring Component Fuel Pump e Sensor loose or air gap incorrect Fault Circuit High Voltage Crankshaft Position Sensor Wheel Condition Shorted connection Related Conclusion Fuel Pump Related e Damaged teeth Fuel d int lly helen iene Sete
134. lay Output o o 19 Malfunction Indicator Light MIL o o 20 Not Used Tach Output if needed 21 Not Used 22 Ignition Coil 1 Output 23 Ignition Coil 2 Output 24 TPS Initialization Terminal 24 690 02 Rev E KohlerEngines com 63 EFI SYSTEM BOSCH 64 ERAS Connector JI s of ten Zeie voltage and D s horn It is recommended that ge to crcuits 94 85 and Ji 2 os the key js swept from UI risa 4 0 Vel ty o ect MP e to prevent differences between actuator voltages circuits 65 66 45 and 8 signo errors load circuits e horn lights sholl mot be powered from the EFI engine or wire chassis me wt switch controls powered circu Ge light Du de an e prevent star and A3 t during event D on circuits 84 85 Ji 2 to pr c stem Installo es Date ME nanton e constont volts an ECU rese ie 2 reel EE E ampere ETIN KohlerEngines com relay be used to is for counter ciockwise rotation of the TPS Clockwise rotalon connec Shown Switching wires to TPS pins W Se E net be E eg but be attached it an isolator plate or ation the battery must maintain a minimum system voltoge of 7 volts sith a current dres of Al wires are 1BAVG and a adaptive memory battery must maintain 7 volts minimum for the ECU operations during crank specified wires pin t k 3 Voltage is l6Vac 9Vdc With a cold cranking dc voltage of 7Voits is recommend that the ECU hou
135. lization Function Above Max Limit 32 Pin MSE 1 1 Plastic Cased ECU only e Code 51 Injector 1 32 Pin MSE 1 1 Plastic Cased ECU only e Code 52 Injector 2 32 Pin MSE 1 1 Plastic Cased ECU only e Code 55 MIL Light 32 Pin MSE 1 1 Plastic Cased ECU only e Code 56 Pump Relay 32 Pin MSE 1 1 Plastic Cased ECU only e Code 61 End of Fault Blink Code Transmission Diagnostic Aid 3 RUN ON MIL remains on while engine is running Possible causes e Fault codes which turn on MIL when engine is running e Code 21 Engine Speed Synchronization e Code 22 Throttle Position Sensor TPS e Code 23 Engine Control Unit ECU e Code 31 Oxygen Sensor shorted e Code 34 Fuel System permanent adaptation at limit e Code 42 Engine Oil Temperature Sensor e Code 43 TPS Auto Learn Initialization Function Below Min Limit 32 Pin MSE 1 1 Plastic Cased ECU only e Code 44 TPS Auto Learn Initialization e Function Above Max Limit 32 Pin MSE 1 1 Plastic Cased ECU only e Code 51 Injector 1 32 Pin MSE 1 1 Plastic Cased ECU only e Code 52 Injector 2 32 Pin MSE 1 1 Plastic Cased ECU only e Code 55 MIL Light 32 Pin MSE 1 1 Plastic Cased ECU only e Code 56 Pump Relay 32 Pin MSE 1 1 Plastic Cased ECU only e MIL circuit grounded between light and ECU 35 Pin MA 1 7 Metal Cased ECU Pin circuit 31 24 Pin MSE 1 0 Plastic Cased ECU Pin circuit 19 24 690 02 Rev
136. ll flywheel onto crankshaft being careful not to shift woodruff key 3 Install screw and washer 4 Use a flywheel strap wrench or holding tool to hold flywheel Torque screw securing flywheel to crankshaft to 71 6 N m 52 8 ft Ib Install Fan NOTE Position locating tabs on back of fan into locating holes of flywheel 1 Install fan onto flywheel using screws engines with plastic grass screen For engines with a metal grass Screen leave it loosely assembled 2 Torque screws to 9 9 N m 88 in Ib Install Hydraulic Lifters NOTE Hydraulic lifters should always be installed in same position as before disassembly Exhaust lifters are located on output shaft oil pan side of engine while intake lifters are located on fan side of engine Cylinder numbers are embossed on top of crankcase and each oylinder head 1 See Servicing Hydraulic Lifters in Disassembly Inspection and Service 2 Apply camshaft lubricant to bottom surface of each lifter Lubricate hydraulic lifters and lifter bores in crankcase with engine oil 3 Note mark or tag identifying hydraulic lifters as either intake or exhaust and cylinder 1 or 2 Install hydraulic lifters into their appropriate locations in crankcase Do not use a magnet 4 If breather reeds and stops were removed from crankcase reinstall them at this time and secure with screw Torque screw to 4 0 N m 35 in Ib KohlerEngines com 107 Reassembly Cylinder Head Com
137. m 200 in Ib then finally to 41 8 N m 370 in Ib following sequence Install Push Rods and Rocker Arms NOTE Push rods should always be installed in same position as before disassembly 1 Note mark or tag identifying push rod as either intake or exhaust and cylinder 1 or 2 Dip ends of push rods in engine oil and install making sure that each push rod ball seats in its hydraulic lifter socket 2 Apply grease to contact surfaces of rocker arms and rocker arm pivots Install rocker arms and rocker arm pivots on one cylinder head and start screws 3 Torque screws to 11 9 N m 105 in Ib 4 Use a spanner wrench or rocker arm lifting tool to lift rocker arms and position push rods underneath 5 Repeat above steps for remaining cylinder Do not interchange parts from cylinder heads 6 Rotate crankshaft to check for free operation of valve train Check clearance between valve spring coils at full lift Minimum allowable clearance is 0 25 mm 0 010 in Check Assembly Important Rotate crankshaft a minimum of 2 revolutions to check longblock assembly and overall proper operation Install Spark Plugs 1 Check gap using wire feeler gauge Adjust gap to 0 76 mm 0 03 in Install plug into cylinder head Torque plug to 27 N m 20 ft Ib KohlerEngines com 109 Reassembly Install Intake Manifold Torque Sequence 1 Install intake manifold and new gaskets with wiring harness atta
138. m e Poor ground Systems Related Poor system ground from ECU to engine e Ignition spark plug plug wire ignition causing rich running while indicating lean coil e Fuel fuel type quality injector fuel Fuel pump module connection See Fuel pressure too high fuel pump module or Components lift pump e Combustion air air cleaner dirty Code 0201 restricted Component Fuel Injector e Base engine problem rings valves E f e Fuel in crankcase oil Fault Injector 1 Circuit Malfunction e Fuel pump module is over filled Condition Injector damaged or faulty shorted or e Lift pump diaphragm is ruptured open connection Conclusion Injector Related 24 690 02 Rev E e Injector coil shorted or opened Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin Black 5 e Wiring from Ignition ECU Related e Circuit controlling injector 1 damaged KohlerEngines com 43 EFI SYSTEM ECV Code 0202 Code 0336 Component Fuel Injector Component Crankshaft Position Sensor Fault Injector 2 Circuit Malfunction Fault Crankshaft Position Sensor Noisy Signal Condition Injector damaged or faulty shorted or Condition Air gap incorrect loose sensor faulty bad open connection battery shorted or faulty connection Conclusion Injector Related faulty sensor or faulty sensor grounding e Injector coi
139. move jumper wire or connector and remove rubber band from throttle lever Disconnect negative battery cable temporarily to clear all learned adjustments Reconnect battery cable and all external loads Readjust idle speed to equipment manufacturer s specified setting and recheck high speed no load RPM setting Observe overall performance TPS Initialization Procedure For 32 Pin MSE 1 1 Plastic Cased ECU Only Auto Learn Initialization 1 Check that basic engine all sensors fuel fuel pressure and battery are good and functionally within specifications Important 2 54 Remove disconnect ALL external loads from engine belts pumps electric PTO clutch alternator rectifier regulator etc Locate service connector plug in wiring harness To initiate TPS auto learn function connect a jumper wire from TPS initialization pin 24 violet wire to battery voltage pin red wire or use jumper plug with blue jumper wire If using PC based diagnostic tool and software refer to Special Tests in Tools Aids and follow prompts to complete Start engine and immediately observe Malfunction Indicator Light MIL Light should start blinking 4 consecutive times every 2 seconds Remove jumper wire or plug from service connector plug in wiring harness Run engine at full throttle above 3000 RPM to warm up engine and initiate O sensor function in closed loop operation KohlerEngines com Watch
140. mpletes ground circuit energizing injector Valve needle in injector is opened electromagnetically and pressure in high pressure fuel line forces fuel down through inside Director plate at tip of injector contains a series of calibrated openings which directs fuel into manifold in a cone shaped spray pattern Injectors have sequential fueling that open and close once every other crankshaft revolution Amount of fuel injected is controlled by ECU and determined by length of time valve needle is held open also referred to as injection duration or pulse width Time injector is open milliseconds may vary in duration depending on speed and load requirements of engine A high voltage solid state battery ignition system is used with EFI system ECU controls ignition output and timing through transistorized control of primary current delivered to coils Based on input from crankshaft position sensor ECU determines correct firing point for speed at which engine is running At proper instant it interrupts flow of primary current in coil causing electromagnetic flux field to collapse Flux collapse induces an instantaneous high voltage in coil secondary which is strong enough to bridge gap on spark plug Each coil fires every other revolution 24 690 02 Rev E EFI SYSTEM ECV EFI engines are equipped with either a 20 or 25 amp charging system to accommodate combined electrical demands of ignition system and specific application Chargi
141. n or shorted during engine operation Note after key off then key on code 56 would be set also ECU Related e Circuit controlling injector 1 damaged e Circuit controlling fuel pump relay damaged ECU only Component TPS Auto Learn initialization function failed throttle angle out of learning range Fault While performing TPS Auto Learn function measured throttle angle was not within acceptable limits Condition MIL illuminated Engine will continue to run but not properly Upon restart TPS Auto Learn function will run again unless voltage to ECU disconnected to clear memory Conclusion TPS Related e TPS rotated on throttle shaft assembly beyond allowable range e TPS bad Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin 18 to TPS pin 1 ECU pin 4 to TPS pin 2 ECU pin 8 to TPS pin 3 Throttle Body Related e Throttle shaft inside TPS worn broken or damaged e Throttle plate loose or misaligned e Throttle plate bent or damaged allowing extra airflow past or restricting movement ECU Related e Circuit providing voltage or ground to TPS damaged e TPS signal input circuit damaged 24 690 02 Rev E KohlerEngines com 73 EFI SYSTEM BOSCH Code 52 32 Pin MSE 1 1 Plastic Cased ECU only Component Injector 2 circuit open shorted to ground or shorted to battery Fault Injector 2 is not functioning because
142. n 10 a Repair or replace as required b Turn idle speed screw back in to its original setting c Reconnect connector plugs start engine and retest system operation 7 Remove two mounting screws from TPS Save screws for reuse Remove and discard faulty TPS Install replacement TPS and secure with original mounting screws a Reconnect Black and TPS connector plugs b Perform TPS Learn Procedure integrating new sensor to ECU Engine Oil Temperature Sensor A sealed non serviceable assembly A faulty sensor must be replaced If a blink code indicates a problem with temperature sensor it can be tested as follows 1 Remove temperature sensor from breather cover and cap or block sensor hole 2 Wipe sensor clean and allow it to reach room temperature 25 C 77 F 3 Unplug Black connector from ECU 4 With sensor still connected check temperature sensor circuit resistance between Black pin 10 and 14 terminals Value should be 9000 11000 O 5 Unplug sensor from wire harness and check sensor resistance separately across two pins Resistance value should again be 9000 11000 O a If resistance is out of specifications replace temperature sensor b If itis within specifications proceed to Step 6 KohlerEngines com 31 EFI SYSTEM ECV 6 Check circuits input ground from wire harness connector to sensor plug for continuity damage etc Connect one ohmmeter lead to Black pin 14 in wire harness connect
143. n harness Power lead to MIL open or shorted ECU Related e Circuit controlling lamp damaged 74 KohlerEngines com Code 56 32 Pin MSE 1 1 Plastic Cased ECU only Component Fuel pump relay circuit open shorted to ground or shorted to battery Fuel pump ignition coils and fuel injectors will not function because fuel pump relay circuit is either open shorted to ground or may be on continuously if shorted to battery Engine will not run or fuel pump will continue to run when switch is off Fuel Pump Relay Related e Bad fuel pump relay Primary side open or shorted Fault Condition Conclusion Fuel Pump Related e Fuel pump open or shorted internally Engine Wiring Harness Related e Fuel pump fuse F1 open e Broken or shorted wire in harness ECU pin 28 to fuel pump relay pin 86 Ignition switch to fuel pump relay pin 85 ECU Related e Circuit controlling fuel pump relay damaged Code 61 Component Fault Condition Denotes end of fault codes If signaled first no other fault codes are present Conclusion Troubleshooting Flow Chart Following flow chart provides an alternative method of troubleshooting EFI system Chart will enable you to review entire system in about 10 15 minutes Using chart accompanying diagnostic aids listed after chart and any signaled fault codes you should be able to quickly locate any problems wit
144. n only rich e Restricted return line causing excessive fuel pressure e Fuel inlet screen plugged in tank fuel pump only e Incorrect fuel pressure at fuel rail Oxygen Sensor Related e Sensor connector or wiring problem e Sensor contaminated or damaged e Exhaust leak e Poor ground path e Pin circuit wiring or connectors Pin 11 for 24 Pin MSE 1 0 Plastic Cased ECU Pin 20 for 32 Pin MSE 1 1 Plastic Cased ECU TPS Sensor Related e Throttle plate position incorrectly set or registered during Initialization e TPS problem or malfunction Engine Wiring Harness Related e Difference in voltage between sensed voltage pin circuit 17 for metal cased ECU pin circuit 2 for plastic cased ECU and actual injector voltage circuit 45 45A Systems Related e Ignition spark plug plug wire ignition coil e Fuel fuel type quality injector fuel pump fuel pressure e Combustion air air cleaner dirty restricted intake leak throttle bores Base engine problem rings valves Exhaust system leak Fuel in the crankcase oil Blocked or restricted fuel return circuit to tank ECU Harness Related e ECU to harness connection problem Code 34 Component Oxygen Sensor Fuel System Components Fault Long term fuel adaptation control is at upper or lower limit Condition System operates closed loop No appreciable performance loss as long as temporary adaptation can provide suff
145. n or oxidation on terminals can interfere with milliamp currents used in system operation Cleaning connectors and grounds will solve problems in many cases In an emergency situation simply disconnecting and reconnecting connectors may clean up contacts enough to restore operation at least temporarily If a fault code indicates a problem with an electrical component disconnect ECU connector and test for continuity between component connector terminals and corresponding terminals in ECU connector using an ohmmeter Little or no resistance should be measured indicating that wiring of that particular circuit is OK 24 KohlerEngines com Crankshaft position sensor is essential to engine operation constantly monitoring rotation and speed RPM of crankshaft There are 23 consecutive teeth cast into flywheel One tooth is missing and is used to reference crankshaft position for ECU Inductive crankshaft position sensor is mounted 0 20 0 70 mm 0 008 0 027 in from flywheel During rotation an AC voltage pulse is created within sensor for each passing tooth ECU calculates engine speed from time interval between consecutive pulses gap from missing tooth creates an interrupted input signal corresponding to specific crankshaft position near BDC for cylinder 1 This signal serves as a reference for control of ignition timing by ECU Synchronization of inductive speed pickup and crankshaft position takes place during first two revolutions
146. n towel 3 Lower chucked push rod until it contacts plunger in lifter Slowly pump plunger 2 or 3 times to force oil out of feed hole in side of lifter Disassemble Cylinder Heads NOTE These engines use valve stem seals on intake and exhaust valves Use a new seal whenever valve is removed or if seal is deteriorated or damaged in any way Never reuse an old seal 1 Remove screws rocker arm pivots and rocker arms from cylinder head 2 Compress valve springs using a valve spring compressor 3 Once valve spring is compressed remove valve spring keepers then remove following items e Valve spring retainers e Valve springs e Valve spring caps e ntake and exhaust valve mark position e Valve stem and seals intake and exhaust 4 Repeat above procedure for other cylinder head Do not interchange parts from one cylinder head to other KohlerEngines com 95 Disassembly Inspection and Service Inspection and Service Valve Details EXHAUST VALVE Sy INTAKE VALVE 5 elll A Ben H M Lk EXHAUST Zi INSERT ZZ OB INTAKE A INSERT Dimension Intake Exhaust A Seat Angle 89 89 B Insert O D 36 987 37 013 mm 1 4562 1 4572 in 32 987 33 013 mm 1 2987 1 2997 in C Guide Depth 4 mm 0 1575 in 6 5 mm 0 2559 in D Guide LD 7 038 7 058 mm 0 2771 0 2779 in 7 038 7 058 mm 0 2771 0 2779 in E Valve Head Diameter 33 37 33 63 mm 1 3138 1 3240 in 29 37 29 63 mm
147. nada 24 690 02 Rev E KohlerEngines com 3 Maintenance OIL RECOMMENDATIONS We recommend use of Kohler oils for best performance Other high quality detergent oils including synthetic of API American Petroleum Institute service class SJ or higher are acceptable Select viscosity based on air temperature at time of operation as shown in table below F 20 0 20 32 40 50 60 80 100 PC 30 20 10 0 10 20 30 40 FUEL RECOMMENDATIONS WARNING Explosive Fuel can cause fires and severe burns 4 4 Do not fill fuel tank while engine is hot or running Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved containers in well ventilated unoccupied buildings away from sparks or flames Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition Never use gasoline as a cleaning agent NOTE E15 E20 and E85 are NOT approved and should NOT be used effects of old stale or contaminated fuel are not warrantable Fuel must meet these requirements e Clean fresh unleaded gasoline e Octane rating of 87 R M 2 or higher e Research Octane Number RON 90 octane minimum e Gasoline up to 10 ethyl alcohol 90 unleaded is acceptable e Methyl Tertiary Butyl Ether MTBE and unleaded gasoline blend max 15 MTBE by volume are approved e Do not add oil to gasoline e Do not ove
148. ncrease when load is applied 2 Remove connector from rectifier regulator With engine running at 3600 RPM measure AC voltage across stator leads using an AC voltmeter Condition Conclusion Voltage is 28 volts or Stator is OK Rectifier more regulator is faulty replace Voltage is less than 28 Stator is faulty replace volts Test stator further using an ohmmeter steps 3 and 4 3 With engine stopped measure resistance across stator leads using an ohmmeter 24 690 02 Rev E Condition Conclusion Resistance is 0 064 0 2 ohms Stator is OK Resistance is 0 ohms Resistance is infinity ohms Stator is shorted replace Stator is open replace 4 With engine stopped measure resistance from each stator lead to ground using an ohmmeter Condition Conclusion Resistance is infinity ohms no continuity Stator is OK not shorted to ground Resistance or continuity measured Stator leads are shorted to ground replace To test charging system for battery continuously charging at high rate 1 With engine running at 3600 RPM measure voltage from B lead to ground using a DC voltmeter Condition Conclusion Voltage is 14 7 volts or less Charging system is OK Battery is unable to hold charge service or replace Voltage is more than 14 7 volts Faulty rectifier regulator replace Kohler
149. nd 40 913 40 935 mm 1 6107 1 6116 in 40 843 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in 40 913 40 935 mm 1 6107 1 6116 in 40 843 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in 40 913 40 935 mm 1 6107 1 6116 in 40 84 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in 40 913 40 935 mm 1 6107 1 6116 in 40 84 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in Connecting Rod Journal O D New O D Max Wear Limit Max Taper Limit Max Out of Round Limit 35 950 35 973 mm 1 4153 1 4163 in 35 941 mm 1 4150 in 0 018 mm 0 0007 in 0 025 mm 0 0010 in 35 955 35 973 mm 1 4156 1 4163 in 35 94 mm 1 415 in 0 018 mm 0 0007 in 0 025 mm 0 0010 in Crankshaft T I R PTO End Crank in Engine Entire Crank in V Blocks 0 279 mm 0 0110 in 0 10 mm 0 0039 in 0 279 mm 0 0110 in 0 10 mm 0 0039 in Cylinder Bore Max Out of Round Max Taper Bore I D 80 000 80 025 mm 83 006 83 031 New 3 1496 3 2689 in mm 82 988 83 013 mm 3 2672 3 2682 in 3 2680 3 2689 in Max Wear Limit 80 075 mm 83 081 mm 83 051 mm 3 2697 in 3 1526 in 3 2709 in 0 120 mm 0 0047 in 0 05 mm 0 0020 in 0 12 mm 0 0047 in 0 05 mm 0 0020 in Cylinder Head Max Out of Flatness 0 076 mm 0 003 in 0 076 mm 0 003 in Values are in Metric units Values in parentheses are English equivalents 24 690
150. nditions for closed loop operation above are not being met ECU is brain or central processing computer of entire EFI system During operation sensors continuously gather data which is relayed through wiring harness to input circuits within ECU Signals to ECU include ignition on off crankshaft position and speed RPM throttle position oil temperature intake air temperature exhaust oxygen levels manifold absolute pressure and battery voltage KohlerEngines com 23 EFI SYSTEM ECV ECU compares input signals to programmed maps in its memory to determine appropriate fuel and spark requirements for immediate operating conditions ECU then sends output signals to set injector duration and ignition timing ECU continually performs a diagnostic check of itself each of sensors and system performance If a fault is detected ECU can turn on a Malfunction Indicator Light MIL if equipped on equipment control panel store fault code in its fault memory and go into a default operating mode Depending on significance or severity of fault normal operation may continue A technician can access stored fault code using a blink code diagnosis flashed out through MIL An optional computer software diagnostic program is also available see Tools and Aids ECU requires a minimum of 6 0 volts to operate To prevent engine over speed and possible failure a rev limiting feature is programmed into ECU If maximum RPM limit 4500 is ex
151. nector and look for corrosion in connector 4 Try reconnecting sensor and observe if problem has cleared 5 Correct any problems found during visual check 24 690 02 Rev E EFI SYSTEM ECV Removal Inspection NOTE Apply anti seize compound only to threads Sensor Signal Observation NOTE Do not cut into or pierce sensor or engine 24 690 02 Rev E wiring to make this connection Sensor produces a very small signal Corrosion or damage to wiring could lead to an incorrect signal because of repairs or contamination to sensor Using a voltmeter or diagnostic software observe voltage before engine is started With key ON voltage should read about 1 0 volt This voltage is generated by ECU If it is not present disconnect sensor and observe voltage at harness connector If voltage is now present there is a short in sensor or associated wiring and corrective action should be taken If voltage still is not present there is a problem with ECU or engine harness Reconnect sensor and start engine Run engine at sufficient speed to bring sensor up to operating temperature Maintain for 1 to 2 minutes to ensure that engine has gone closed loop Once in closed loop sensor voltage should cycle between about 100 to 250 mv low speed idle and 700 to 900 mv high speed no load If this cycling is not observed a determination must be made if problem is with engine or sensor Check engine harness for battery voltage on heater ci
152. new studs as described in Step 3 Do not use reinstall any loosened or removed studs 3 Install new mounting stud s into crankcase a Thread and lock mounting nuts together on smaller diameter threads b Thread opposite end of stud with preapplied locking compound into crankcase until specified height from crankcase surface is achieved When threading in studs use a steady tightening motion without interruption until proper height is obtained Otherwise frictional heat from engaging threads may cause locking compound to set up prematurely 24 690 02 Rev E Reassembly Studs closest to lifters must have an exposed height of 75 mm 2 15 16 in Studs furthest from lifters must have an exposed height of 69 mm 2 3 4 in c Remove nuts and repeat procedure as required 4 Check that dowel pins are in place and install a new cylinder head gasket part number facing up 5 Install cylinder head Match numbers on cylinder heads and crankcase Make sure head is flat on gasket and dowel pins 6 Lightly lubricate exposed upper threads of studs with engine oil Install a flat washer and nut onto each of mounting studs Torque nuts in 2 stages first to 16 9 N m 150 in Ib then finally to 33 9 N m 300 in Ib following sequence Heads secured with screws 2 Install a new cylinder head gasket part number facing up 3 Install cylinder head and start screws 4 Torque screws in 2 stages first to 22 6 N
153. ng acceleration or triggering of fault codes related to fuel delivery Injector clogging is usually caused by a buildup of deposits on director plate restricting flow of fuel resulting in a poor spray pattern Some contributing factors to injector clogging include higher than normal operating temperatures short operating intervals and dirty incorrect or poor quality fuel Cleaning of clogged injectors is not recommended they should be replaced Additives and higher grades of fuel can be used as a preventative measure if clogging has been a problem Ignition Coil If a coil is determined to be faulty replacement is necessary An ohmmeter may be used to test wiring and coil windings NOTE Do not ground primary coil with ignition ON as they may overheat or spark NOTE Always disconnect spark plug lead from spark plug before performing following tests NOTE If ignition coil s are disabled and an ignition fault is registered system will automatically disable corresponding fuel injector drive signal Fault must be corrected to ignition coil and ECU power switch must be turned OFF for 10 seconds for injector signal to return This is a safety measure to prevent bore washing and oil dilution Testing Using an ohmmeter set on Rx1 scale check resistance in circuits as follows 1 To check cylinder coil 1 starter side disconnect Black connector from ECU and test between Black pins 1 and 15 To check cylinder coil 2 oil
154. ng system troubleshooting information is provided in Electrical System An electric fuel pump module and a lift pump two types are used to transfer fuel in EFI system Three types of lift pumps are a pulse fuel pump a mechanical fuel pump or a low pressure electric fuel pump Pumping action is created by either oscillation of positive and negative pressures within crankcase through a hose or by direct lever pump actuation off rocker arm movement Pumping action causes diaphragm on inside of pump to pull fuel in on its downward stroke and to push it into fuel pump module on its upward stroke Internal check valves prevent fuel from going backward through pump Fuel pump module receives fuel from lift pump increases and regulates pressure for fuel injectors Fuel pump module is rated for a minimum output of 13 5 liters per hour and regulated at 270 kilo pascals 39 psi When key switch is turned ON and all safety switch requirements are met ECU activates fuel pump module for about six seconds which pressurizes system for start up If key switch is not promptly turned to start position engine fails to start or engine is stopped with key switch ON as in case of an accident ECU switches off pump preventing continued delivery of fuel In this situation MIL will go on but it will go back off after 4 cranking revolutions if system function is OK Once engine is running fuel pump remains on Precision components inside fuel pump m
155. ngine temperature sensor Faulty injectors Engine Misses Hesitates or Stalls Under Load Low Power Fuel injector s fuel filter fuel line or fuel pick up dirty restricted Dirty air cleaner Insufficient fuel pressure or fuel delivery Vacuum intake air leak Improper governor setting adjustment or operation TPS faulty mounting problem or TPS Initialization Procedure incorrect Bad coil s spark plug s or wires Faulty malfunctioning ignition system Dirty air filter Insufficient fuel delivery Improper governor adjustment Plugged restricted exhaust One injector not working Basic engine problem exists TPS faulty or mounting exists Throttle plate in throttle body not fully opening to WOT stop if equipped 38 KohlerEngines com 24 690 02 Rev E Function Test EFI SYSTEM ECV Fault Codes Example of Diagnostic Display A WARNING High Pressure Fluids can puncture skin and E E E E bul E b x Xt 2 jee cause severe injury or death One second pause Do not work on fuel system without proper 1 training or safety equipment G i au Fluid puncture injuries are highly toxic and hazardous One second pause 0107 If an injury occurs seek immediate medical attention Lt pe Et E p L3 It Iit Lj Et 0 Function of fuel system is to provide sufficient deli
156. nnect Black connector from ECU 5 Connect an ohmmeter between 4 and 13 pin terminals A resistance value of 325 395 O at room temperature 20 C 68 F should be obtained If resistance is correct check mounting air gap flywheel teeth damage run out etc and flywheel key 6 Disconnect crankshaft position sensor connector from wiring harness Test resistance between terminals A reading of 325 395 O should again be obtained a If resistance is incorrect remove screws securing sensor to mounting bracket and replace sensor b If resistance in step 5 was incorrect but resistance of sensor alone was correct test wire harness circuits between sensor connector terminals and corresponding pin terminals 4 and 13 in main connector Correct any observed problem reconnect sensor and perform step 5 again 7 When fault is corrected and engine starts clear fault codes following ECU Reset procedure Throttle Position Sensor TPS gt A Resistance Table Throttle Between Resistance T Position Terminal Value Q Continuity Closed A amp C 1400 1800 Yes Full with Stop Pin A amp C 3200 4100 Yes Full without Stop Pin A amp C 4600 5200 Yes Any A amp B 3000 7000 Yes TPS is a sealed non serviceable assembly If diagnosis indicates a bad sensor complete replacement is necessary If a blink code indicates a problem with TPS it can be tested as follows 1 Counting number of turn
157. ns are met e Oil temperature is greater than 35 C 95 F e Oxygen sensor has warmed sufficiently to provide a signal minimum 375 C 709 F e Engine operation is at a steady state not starting warming up accelerating etc During closed loop operation ECU has ability to readjust temporary and learned adaptive controls providing compensation for changes in overall engine condition and operating environment so it will be able to maintain ideal air fuel ratio This system requires a minimum engine oil temperature greater than 80 C 176 F to properly adapt These adaptive values are maintained as long as ECU is not reset During certain operating periods such as cold starts warm up acceleration etc an air fuel ratio richer than 14 7 1 is required and system operates in an open loop mode In open loop operation oxygen sensor output is not used and controlling adjustments are based on primary sensor signals and programmed maps only System operates open loop whenever three conditions for closed loop operation above are not being met ECU is a brain or central processing computer of entire EFI fuel ignition management system During operation sensors continuously gather data which is relayed through wiring harness to input circuits within ECU Signals to ECU include ignition on off crankshaft position and speed RPM throttle position oil temperature exhaust oxygen levels and battery voltage ECU compar
158. nts Do not disconnect or reconnect ECU wiring harness connector or any individual components with ignition on This can send a damaging voltage spike through ECU Do not allow battery cables to touch opposing terminals When connecting battery cables attach positive cable to positive battery terminal first followed by negative cable to negative battery terminal Never start engine when cables are loose or poorly connected to battery terminals Never disconnect battery while engine is running Never use a quick battery charger to start engine Do not charge battery with key switch ON Always disconnect negative battery cable before charging battery and also unplug harness from ECU before performing any welding on equipment Initial Starting Priming Procedure Important EFI fuel system must be purged of air primed prior to initial start up and or any time system has been disassembled or fuel tank run dry 1 Locate electronic control unit ECU for EFI system Check part number on end If part no is 24 584 28 or higher ECU has a built in priming feature a Turn key switch to ON RUN position You will hear fuel pump cycle on and off When fuel pump stops cycling approximately one minute system is primed start engine 2 For plastic cased ECU s below 24 584 28 S system can be primed by manually cycling fuel pump KohlerEngines com 51 EFI SYSTEM BOSCH a Turn key switch to ON RUN position F
159. nts can 4 4 cause severe injury or death Use only in well ventilated areas away from ignition sources A WARNING High Pressure Fluids can puncture skin and cause severe injury or death S D I Do not work on fuel system without proper training or safety eguipment Carburetor cleaners and solvents are extremely flammable Follow cleaner manufacturer s warnings and instructions on its proper and safe use Never use gasoline as a cleaning agent Fluid puncture injuries are highly toxic and hazardous If an injury occurs seek immediate medical attention KohlerEngines com A WARNING Explosive Fuel can cause fires and severe burns lt Fuel system ALWAYS remains under HIGH PRESSURE Wrap a shop towel completely around fuel pump module connector Press release button s and slowly pull connector away from fuel pump module allowing shop towel to absorb any residual fuel in high pressure fuel line Any spilled fuel must be completely wiped up immediately 24 690 02 Rev E Maintenance MAINTENANCE INSTRUCTIONS E A WARNING Accidental Starts can cause severe injury or Before working on engine or equipment disable engine as Fe death follows 1 Disconnect spark plug lead s 2 Disconnect Disconnect and ground spark plug lead s negative battery cable from battery X before servicing Normal maintenance re
160. numbered on crankcase Use numbers to mark each end cap connecting rod and piston for reassembly Do not mix end caps and connecting rods 1 Remove screws securing closest connecting rod end cap Remove end cap 2 Carefully remove connecting rod and piston assembly from cylinder bore 3 Repeat above procedure for other connecting rod and piston assembly 100 KohlerEngines com 4 Remove piston pin from piston for inspection Use a small screwdriver to pry pin retainer out of groove Inspection Piston and Rings Components and Details A Piston Ring B End Gap C Identification Mark D Piston E Top Compression F Center Compression Ring Ring G Rails H Expander I Oil Control Ring J 3 Piece Scuffing and scoring of pistons and cylinder walls occurs when internal engine temperatures approach welding point of piston Temperatures high enough to do this are created by friction which is usually attributed to improper lubrication and or overheating of engine Normally very little wear takes place in piston boss piston pin area If original piston and connecting rod can be reused after new rings are installed original pin can also be reused but new piston pin retainers are required Piston pin is included as part of piston assembly if pin boss in piston or pin are worn or damaged a new piston assembly is required Dye Colored Stripe 24 690 02 Rev E Ring failure is usually indicate
161. ockwise until it stops Use only enough pressure to hold it in that position 4 Check how end of throttle linkage aligns with bushing hole in governor lever It should fall in center of hole If it doesn t perform adjustment procedure as follows B Setting Initial Adjustment 1 Check split where clamping screw goes through governor lever There should be a gap of at least 1 32 If tips are touching and there is no gap present lever should be replaced If not already installed position governor lever on cross shaft but leave clamping screw loose 2 Follow instructions in Step 2 of Checking Initial Adjustment then reattach throttle linkage to governor lever with bushing clip It is not necessary to reattach damper or governor springs at this time 3 Insert a nail into hole in top of cross shaft Using light pressure rotate governor shaft counterclockwise as far as it will turn then torque nut on clamping screw to 6 8 N m 60 in Ib Make sure that governor arm has not twisted up or down after nut has been tightened 24 690 02 Rev E EFI SYSTEM BOSCH 4 Verify that governor has been set correctly With linkage still retained in FULL THROTTLE position Step 2 unsnap bushing clip separate linkage from bushing and remove bushing from lever Follow Steps 3 and 4 in Checking Initial Adjustment 5 Reconnect dampening spring into its governor lever hole from bottom Reinstall bushing and reattach throttle linkage Reatta
162. odule are not serviceable DO NOT attempt to open fuel pump module Damage to components will result and warranty will be void Because fuel pump module is not serviceable engines are equipped with a special 10 micron EFI fuel filter to prevent harmful contamination from entering module If there are two filters in system one before lift pump will be a standard 51 75 micron filter and one after lift pump will be special 10 micron filter Be sure to use an approved 10 micron filter for replacement High pressure fuel line is an assembly of hoses injector caps and a fuel connector to fuel pump module High pressure fuel line feeds fuel to top of injectors through injector caps Caps are fastened to intake manifold and injectors are locked into place A small retaining clip provides a secondary lock KohlerEngines com 25 EFI SYSTEM ECV High pressure fuel line is serviced as a complete assembly to prevent tampering and safety hazards Components are not individually serviceable Vent hose assembly is intended to vent fuel vapor out of fuel pump module and direct fuel vapor into throttle body All EFI engines are equipped with an engine mounted purge port on 2 cylinder barrel baffle This capped purge port can be used by OEM to vent fuel tanks or used in conjunction with a carbon canister kit for Tier III evaporative emissions compliance Purge port connects to vent hose assembly and directs all fuel vapor into throttle body If p
163. ols KLR 82407 For holding flywheel of CS series engines Flywheel Puller SE Tools KLR 82408 For properly removing flywheel from engine Flywheel Strap Wrench SE Tools KLR 82409 For holding flywheel during removal 24 690 02 Rev E KohlerEngines com 15 Tools and Aids TOOLS Description Source Part No Hydraulic Valve Lifter Tool For removing and installing hydraulic lifters Kohler 25 761 38 S Ignition System Tester For testing output on all systems including CD Kohler 25 455 01 S Inductive Tachometer Digital For checking operating speed RPM of an engine Design Technology Inc DTI 110 Offset Wrench K and M Series For removing and reinstalling cylinder barrel retaining nuts Kohler 52 455 04 S Oil Pressure Test Kit For testing verifying oil pressure on pressure lubricated engines Kohler 25 761 06 S Radiator Tester For pressure testing radiator and cap on Aegis liquid cooled engines Kohler 25 455 10 S Rectifier Regulator Tester 120 volt current Rectifier Regulator Tester 240 volt current For testing rectifier regulators Components of 25 761 20 S and 25 761 41 S CS PRO Regulator Test Harness Special Regulator Test Harness with Diode Spark Advance Module SAM Tester For testing SAM ASAM and DSAM on engines with SMART SPARK Starter Servicing Kit All Starters For removing and reinstalling drive retaining rings and brushes Individual component
164. on coils and fuel injectors is controlled by ECU which grounds their respective ground circuits at proper times Fuel injectors mount into throttle body intake manifold and fuel rail attaches to them at top end Replaceable O Rings on both ends of injector prevent external fuel leakage and also insulate it from heat and vibration A special clip connects each injector to fuel rail and holds itin place O Rings must be replaced anytime injector is removed When key switch is on and relay is closed fuel rail is pressurized and voltage is present at injector At proper instant ECU completes ground circuit energizing injector Valve needle in injector is opened electromagnetically and pressure in fuel rail forces fuel down through inside Director plate at tip of injector contains a series of calibrated openings which directs fuel into manifold in a cone shaped spray pattern Injector is opened and closed once for each crankshaft revolution however only one half total amount of fuel needed for one firing is injected during each opening Amount of fuel injected is controlled by ECU and determined by length of time valve needle is held open also referred to as injection duration or pulse width It may vary in length from 1 5 8 milliseconds depending on speed and load requirements of engine 24 690 02 Rev E A high voltage solid state battery ignition system is used with EFI system ECU controls ignition output and timing through t
165. or as in step 4 Connect other lead to terminal 1 in sensor plug Continuity should be indicated Repeat test between Black pin 10 and terminal 2 in sensor plug Intake Air Temperature Sensor A non serviceable component Complete replacement is required if it is faulty Sensor and wiring harness can be checked as follows 1 Remove temperature sensor from throttle body 2 Allow it to reach room temperature 20 C 68 F 3 Unplug Black connector from ECU 4 With sensor still connected check temperature sensor circuit resistance between Black pin 10 and 8 pin terminals Value should be 3100 3900 O 5 Unplug sensor from wire harness and check sensor resistance separately across two pins Resistance value should again be 3100 3900 O a If resistance is out of specifications replace temperature sensor b If itis within specifications proceed to Step 6 6 Check circuits input ground from main harness connector to sensor plug for continuity damage etc Connect one ohmmeter lead to Black pin 8 in main harness connector as in step 4 Connect other lead to terminal 1 in sensor plug Continuity should be indicated Repeat test between Black pin 10 and terminal 2 in sensor plug Oxygen Sensor O Components 32 KohlerEngines com Cutaway Oxygen Sensor Components 0 Planar Element A Protection Shield B and Heater Stainless Steel C Lower Insulator D Housing E
166. ormance with optimum fuel efficiency and lowest possible emissions Ignition and injection functions are electronically controlled monitored and continually corrected during operation to maintain ideal air fuel ratio Central component of system is Engine Control Unit ECU which manages system operation determining best combination of fuel mixture and ignition timing for current operating conditions 24 690 02 Rev E EFI SYSTEM ECV A lift fuel pump is used to move fuel from tank through an in line fuel filter and fuel line Fuel is then pumped to fuel pump module Fuel pump module regulates fuel pressure to a system operating pressure of 39 psi Fuel is delivered from fuel pump module through high pressure fuel line into injectors which inject fuel into intake ports ECU controls amount of fuel by varying length of time that injectors are on This can range from 2 to over 12 milliseconds depending on fuel requirements Controlled injection of fuel occurs every other crankshaft revolution or once for each 4 stroke cycle When intake valve opens air fuel mixture is drawn into combustion chamber compressed ignited and burned ECU controls amount of fuel being injected and ignition timing by monitoring primary sensor signals for engine temperature speed RPM and throttle position load These primary signals are compared to preprogrammed maps in ECU computer chip and ECU adjusts fuel delivery to match mapped values After engin
167. orque Sequence Oil pump is mounted inside oil pan If service is required continue with Disassembly Inspection and Reassembly Disassembly 1 2 3 Remove screws Remove oil pump assembly from oil pan Remove oil pump rotor Unhook locking clip and care fully pull it free from oil pump housing Relief valve is a one piece style staked to oil pump housing Removal should not be attempted nor is internal servicing possible If a problem with relief valve is encountered oil pump should be replaced Inspection Inspect oil pump housing gear and rotors for nicks burrs wear or any visible damage If any parts are worn or damaged replace oil pump Reassembly 1 24 690 02 Rev E Install oil pickup to oil pump body Lubricate O ring with oil and make sure it remains in groove as pickup is being installed Install rotor Install oil pump body to oil pan and secure with screws Torque screws as follows a Install fastener into location 1 and lightly tighten to position pump b Install fastener into location 2 and fully torque to recommended value c Torque fastener in location 1 to recommended value First Time Installation 10 7 N m 95 in Ib All Reinstallations 6 7 N m 60 in Ib After torquing rotate gear and check for freedom of movement Make sure there is no binding If binding occurs loosen screws reposition pump retorque screws and recheck movement
168. other sensors already discussed oxygen sensor is a non serviceable component Complete replacement is reguired if it is faulty Sensor and wiring harness can be checked as follows 1 Oxygen sensor must be hot minimum of 400 C 752 F Run engine for about 5 minutes With engine running disconnect oxygen sensor lead from wiring harness Set VOA meter for DC volts and connect red lead to disconnected sensor lead and black lead to sensor shell Look for a voltage reading from 0 2 v 1 0 v a If voltage is in specified range go to Step 2 b If voltage is not in specified range reconnect oxygen sensor lead With lead connected probe or connect sensor connection with red VOA meter lead Attach black VOA meter lead to a good ground location Start and run engine at 3 4 throttle and note voltage reading being signaled by oxygen sensor Reading should cycle between 0 2 v and 1 0 v which indicates oxygen sensor is functioning normally and fuel delivery is within prescribed parameters If voltage readings show a steady decline rev engine and check indicated reading again If voltage momentarily increases and then again declines without cycling engine may be running lean due to incorrect TPS initialization Shut off engine perform TPS initialization and then repeat test If TPS initialization cannot be achieved perform step c EFI SYSTEM BOSCH c Replace oxygen sensor see next page Run engine long enough to bring new sensor up
169. ottle control bracket to previously marked hole in governor lever Install Air Cleaner Assembly Refer to Air Cleaner Intake for air cleaner reassembly procedure Heavy Duty Air Cleaner 1 Install air cleaner assembly onto throttle body mounting studs Secure and torque nuts to 7 4 9 0 N m 65 5 80 in Ib 2 Install and tighten two upper mounting screws securing air cleaner to mounting bracket Torque screws to 9 9 N m 88 in Ib Low Profile Air Cleaner 1 Verify O ring is present around machined O D of throttle body and place air cleaner base onto throttle body studs Secure air cleaner base using three nuts Attach air cleaner base bracket to cylinder heads with screws behind any control panel or bracket Attach air cleaner base to lower bracket with M5 screws through lower section of base Torque nuts to 7 4 9 0 N m 65 5 80 in Ib and lower M5 mounting screws to 2 3 N m 20 in Ib 2 Install air cleaner components as described in Air Cleaner Intake Setting Initial Governor Adjustment 1 Move governor lever toward throttle body as far as it will go wide open throttle and hold in position 2 Insert a nail into hole on cross shaft and rotate shaft counterclockwise as far as it will turn then torque nut to 7 1 N m 63 in Ib Install Muffler 1 Install port liners if equipped Install exhaust gaskets and muffler Install oxygen sensor torque to 50 1 N m 37 ft Ib and connect to wire
170. ottle linkage from governor lever 3 Loosen nut and remove governor lever from cross shaft 24 690 02 Rev E KohlerEngines com 91 Disassembly Inspection and Service WARNING Explosive Fuel can cause fires and severe burns A 4 4 Do not fill fuel tank while engine is hot or running Gasoline is extremely flammable and its vapors can explode if ignited Store gasoline only in approved containers in well ventilated unoccupied buildings away from sparks or flames Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition Never use gasoline as a cleaning agent Fuel Pump Remove Lift Fuel Pump and Fuel Pump Module A ey Outlet to Fuel Pump A Pulse Pump B Inlet Hose C Module D Pulse Hose Fuel Pump Module High Pressure Fuel E Electrical Connector F Fuel Pump Module G Baffle H Line Connector Oetiker Clamp Remove Lift Fuel Pump Remove Fuel Pump Module ECV EFI 1 2 3 Pul 1 2 3 4 92 Disconnect inlet and outlet fuel lines at lift pump Disconnect pulse vacuum hose at lift fuel pump from crankcase Remove screws securing lift fuel pump to bracket se Style Pumps CV Disconnect fuel line at in line fuel filter on tank to pulse pump line Disconnect pulse vacuum line from crankcase Remove screws securing fuel pump to bracket on blower housing Note or mark orientation of
171. p Fastener first to 2 8 N m 25 in Ib finally to 2 3 N m 20 in Ib Rectifier Regulator Fastener Intake Manifold 1 4 N m 12 6 in Ib Mounting Fastener torque in 2 increments first to 7 8 N m 69 in Ib first to 7 4 N m 66 in Ib finally to 10 5 N m 93 in Ib finally to 9 9 N m 88 in Ib Manifold Absolute Pressure MAP Sensor Fastener 7 3 N m 65 in Ib Air Cleaner to Throttle Body Fastener 8 2 N m 73 in Ib Bracket for Heavy Duty Air Cleaner to Intake 9 9 N m 88 in Ib Fuel Injector Cap Fastener 7 3 N m 65 in Ib Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 8 KohlerEngines com 24 690 02 Rev E TORQUE SPECIFICATIONS Muffler ECV630 ECV680 ECV730 ECV749 Specifications CV26 CV735 CV745 Retaining Nut 27 8 N m 246 in Ib 24 4 N m 216 in Ib Oxygen Sensor 50 1 N m 37 ft Ib Oil Cooler Oil Cooler Adapter Nipple 28 5 N m 21 ft Ib 27 N m 20 ft Ib Fastener Top 2 8 N m 25 in Ib Bottom 2 3 N m 20 in Ib Oil Pan Fastener 25 6 N m 227 in Ib 24 4 N m 216 in Ib Speed Control Bracket Fastener Assembled to Cylinder Heads 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes Fastener Assembled to Blower Housing 2 8 N m 2
172. placement or repair of emission control devices and systems may be performed by any repair establishment or individual however warranty repairs must be performed by a Kohler authorized dealer MAINTENANCE SCHEDULE Every 25 Hours or Annually e Service replace low profile precleaner if equipped Air Cleaner Intake Every 100 Hours or Annually e Change oil Lubrication System e Replace low profile air cleaner element Air Cleaner Intake e Remove and clean shrouds and cooling areas Air Cleaner Intake e Check oil cooler fins clean as necessary if equipped Lubrication System Every 150 Hours e Check heavy duty filter minder Air Cleaner Intake e Inspect heavy duty air filter paper element and inlet screen area Air Cleaner Intake Every 200 Hours e Replace unique Electronic Fuel Injection EFI fuel filter Every 200 Hours e Change oil filter Lubrication System e Replace spark plugs and set gap Electrical System Every 300 Hours e Replace heavy duty air cleaner element and check inner element Air Cleaner Intake Every 600 Hours e Replace heavy duty air cleaner inner element Air Cleaner Intake Perform these procedures more frequently under severe dusty dirty conditions REPAIRS SERVICE PARTS Kohler genuine service parts can be purchased from Kohler authorized dealers To find a local Kohler authorized dealer visit KohlerEngines com or call 1 800 544 2444 U S and Ca
173. ponents 2 Se A A Valve Cover Valve Cover Gasket Hex Flange Screw D Rocker Arm Piviot E Rocker Arm Push Rod Hydraulic Lifter H Valve Cap I Valve Keeper Valve Spring Valve Seal L ks M Cylinder Head a Valve P Dowel Pin 108 KohlerEngines com 24 690 02 Rev E Valve Stem Seals These engines use valve stem seals on intake valves and on exhaust valves Use a new seal whenever valve is removed or if seal is deteriorated or damaged in any way Never reuse an old seal Assemble Cylinder Heads Prior to installation lubricate all components with engine oil paying particular attention to lip of valve stem seal valve stems and valve guides Install following items in order listed below using a valve spring compressor Intake and exhaust valves Valve spring retainers Valve springs Valve spring caps Valve spring keepers Install Cylinder Heads Torque Sequence NOTE Cylinder heads must be attached with original type of mounting hardware using either screws or mounting studs with nuts and washers Do not intermix components NOTE Match numbers embossed on cylinder heads and crankcase 1 Check to make sure there are no nicks or burrs on sealing surfaces of cylinder head or crankcase Heads secured with mounting studs nuts and washers 2 Ifall of studs were left intact go to Step 6 If any studs were disturbed or removed install
174. r Black pin 17 Engine Wiring Harness Related e Difference in voltage between sensed voltage and actual sensor voltage e Short in wire harness 42 KohlerEngines com 24 690 02 Rev E EFI SYSTEM ECV Code 0172 Code 0174 Component Fuel System Component Fuel System Fault Minimum adaptation limit exceeded Fault Lean fuel condition Condition Too high pressure at high pressure fuel Condition Fuel inlet screen filter plugged low line TPS malfunction shorted pressure at high pressure fuel line TPS connection faulty sensor or fuel pump malfunction shorted connection or faulty module failure sensor Conclusion Oxygen Sensor Related Conclusion TPS Learn Incorrect e Sensor connector or wiring e Lean condition check oxygen sensor e Sensor contaminated or damaged signal with VOA and see Oxygen e Poor ground path Sensor e Pin circuit wiring or connectors SR ECU Black pin 10 or 17 Engine Wiring Harness Related e Pin circuit wiring or connectors TPS Sensor Related ECU pin Black 10 12 16 and 17 e Throttle plate position incorrect during Learn procedure Low Fuel Pressure e TPS problem or malfunction e Plugged filters e Bad lift pump Engine Wiring Harness Related e Difference in voltage between sensed Oxygen Sensor Related voltage and actual sensor voltage e Sensor connector or wiring problem e Problem in wiring harness e Exhaust leak e ECU to harness connection proble
175. ransistorized control of primary current delivered to coils Based on input from speed sensor ECU determines correct firing point for speed at which engine is running At proper instant it releases flow of primary current to coil Primary current induces high voltage in coil secondary which is then delivered to spark plug Each coil fires every revolution but every other spark is wasted An electric fuel pump is used to transfer fuel in EFI system Depending on application pump may be inside fuel tank or in fuel line near tank Pumps are rated for a minimum output of 25 liters per hour at 39 psi Pumps have an internal 60 micron filter In addition in tank style pumps will have a pre filter attached to inlet In line pump systems may also have a filter between tank and pump on pickup low pressure side When key switch is turned ON and all safety switch requirements are met ECU through relay activates fuel pump which pressurizes system for start up If key switch is not promptly turned to start position engine fails to start or engine is stopped with key switch on as in case of an accident ECU switches off pump preventing continued delivery of fuel In this situation MIL will go on but it will go back off after 4 cranking revolutions if system function is OK Once engine is running fuel pump remains on Fuel pressure regulator assembly maintains required operating system pressure of 39 psi 3 A rubber fiber diaphragm
176. rcuit Anti seize compound will affect sensor performance if it gets into lower shield of sensor If sensor has heavy deposits on lower shield engine oil or fuel may be source If heavy carbon deposits are observed incorrect engine fuel control may be occurring If sensor is at room temperature measure between signal leads black wire Pin C and grey wire Pin D attached to sensor If resistance is less than one megohm sensor has an internal short With sensor at room temperature measure heater circuit resistance purple wire Pin A and white wire Pin B resistance should be 8 1 11 1 O If a damaged sensor is found identify root cause which may be elsewhere in application Refer to Troubleshooting Oxygen Sensor O table A special dry to touch anti seize compound is applied to all new oxygen sensors at factory If recommended mounting thread sizes are used this material provides excellent anti seize capabilities and no additional anti seize is needed If sensor is removed from engine and reinstalled anti seize compound should be reapplied Use an oxygen sensor safe type anti seize compound It should be applied according to directions on label KohlerEngines com 33 EFI SYSTEM ECV Troublshooting Oxygen Sensor O Condition Possible Cause Conclusion Low voltage output Shorted lead wire Shorted sensor or sensor circuit Wiring shorted to ground Replace sensor or repair wiring
177. rease from fuel pump module pins 3 If either injector exhibits leakage of more than two to four drops per minute from tip or shows any sign of leakage around outer shell turn ignition switch OFF and replace injector as follows 4 Depressurize fuel system 5 Clean any dirt accumulation from sealing mounting area of faulty injector s and disconnect electrical connector s 6 Pull retaining clip off top of injector s Remove screw holding injector s from manifold KohlerEngines com 35 EFI SYSTEM ECV 7 Reverse appropriate procedures to install new injector s and reassemble engine Use new O rings and retaining clips any time an injector is removed new replacement injectors include new O rings and retaining clips Lubricate O rings lightly with clean engine oil Use installation tool provided with O rings to install new upper O ring Place tool into fuel injector inlet Place one side of O ring into O ring groove and roll O ring over tool onto fuel injector Torque screw securing fuel injector caps and blower housing mounting screws to 7 3 N m 65 in Ib and intake manifold and air cleaner mounting screws to 10 5 N m 93 in Ib An ECU Reset will need to be completed Injector problems due to dirt or clogging are generally unlikely due to design of injectors high fuel pressure and detergent additives in gasoline Symptoms that could be caused by dirty clogged injectors include rough idle hesitation stumbling duri
178. red fuses are good and a minimum of 7 0 volts is being supplied If during cranking voltage drops below 7 0 volts a reduction of fuel pressure may occur resulting in a lean starting condition If required testing of fuel pump may be conducted 1 Relieve fuel pressure at fuel pump module Fuel pump module may need to be loosened or pulled away from engine Disconnect fuel coupler from fuel pump module and insert pressure test jumper from Kohler EFI Service Kit between high pressure fuel line and fuel pump module 2 Connect black hose of Pressure Tester Route clear hose into a portable gasoline container or equipment fuel tank 3 Turn on key switch to activate pump and check System pressure on gauge It may take several key cycles to compress air introduced into system and reach regulated pressure If system pressure of 39 psi 3 is observed wiring fuel pump and regulator are working properly Turn key switch OFF and depress valve button on tester to relieve system pressure a If pressure is too high or too low replace fuel pump module 4 f pump did not activate step 3 disconnect plug from fuel pump Connect a DC voltmeter across terminals in plug turn on key switch and observe if a minimum of 7 volts is present during six second prime process 24 690 02 Rev E EFI SYSTEM ECV 5 f no voltage is observed connect red lead of meter to red wire of plug and black lead to a good ground while key is still O
179. replacement is necessary Rectifier Regulator NOTE When installing rectifier regulator take note of terminal markings and install plug s accordingly NOTE Disconnect all electrical connections attached to rectifier regulator Testing may be performed with rectifier regulator mounted or loose Repeat applicable test procedure 2 or 3 times to determine condition of part Rectifier regulator is mounted on blower housing To replace disconnect plug s remove mounting screws and ground wire or metal grounding strap Testing rectifier regulator may be performed as follows using appropriate rectifier regulator tester To test 20 25 amp rectifier regulators 1 2 3 4 82 Connect tester ground lead with spring clamp to body of rectifier regulator Connect red lead from tester to middle terminal labeled B Connect black leads from tester to both outer AC terminals on rectifier regulator Plug tester into proper AC outlet power for tester being used Turn on power switch POWER light should be illuminated and one of four status lights may be lit as well This does not represent condition of part Press TEST button until a click is heard and then release Momentarily one of four status lights will illuminate indicating partial condition of part KohlerEngines com 24 690 02 Rev E Condition Electrical System Conclusion 20 25 amp OK green light comes on and stays steady Disconnect tester black lead attache
180. retor adjusted incorrectly e Engine overheated e Faulty spark plug s e Ignition module s faulty or improperly gapped e Incorrect crankshaft position sensor air gap e Interlock switch is engaged or faulty e Loose wires or connections that intermittently ground ignition kill circuit e Quality of fuel dirt water stale mixture e Spark plug lead s disconnected e Spark plug lead boot loose on plug e Spark plug lead loose Engine Will Not Idle e Faulty carburetor e Faulty cylinder head gasket e Faulty or misadjusted choke or throttle controls e Fuel pump malfunction vacuum hose clogged or leaking e Intake system leak e Loose wires or connections that intermittently ground ignition kill circuit e Quality of fuel dirt water stale mixture e Restricted fuel tank cap vent Engine Starts Hard e Engine overheated e Faulty spark plug s e Idle fuel adjusting needle s improperly set e Idle speed adjusting screw improperly set e Inadequate fuel supply e Low compression e Quality of fuel dirt water stale mixture e Restricted fuel tank cap vent Engine Overheats e Clogged fuel line or fuel filter e Engine overheated e Faulty ACR mechanism e Faulty or misadjusted choke or throttle controls e Faulty spark plug s e Flywheel key sheared e Fuel pump malfunction vacuum hose clogged or leaking e Interlock switch is engaged or faulty e Loose wires or connec
181. rfill fuel tank e Do not use gasoline older than 30 days 4 KohlerEngines com STORAGE If engine will be out of service for 2 months or more follow procedure below 1 Add Kohler PRO Series fuel treatment or equivalent to fuel tank Run engine 2 3 minutes to get stabilized fuel into fuel system failures due to untreated fuel are not warrantable 2 Change oil while engine is still warm from operation Remove spark plug s and pour about 1 oz of engine oil into cylinder s Replace spark plug s and crank engine slowly to distribute oil 3 Disconnect negative battery cable 4 Store engine in a clean dry place 24 690 02 Rev E Engine Dimensions with Heavy Duty Air Cleaner Specifications Dimensions in millimeters 17 556 OIL FILTER SIDE ENGINE MOUNTING SURFACE 85 91 OIL DRAIN 3382 PLUG OILFILTER 3 8 NPT INCH 425 17 4 16 739 Inch equivalents shown in 1497 302 02 4 5 314 L 9621 11 891 AIR FILTER 3 788 13003 RAIN CAP 269 29 4 5 119 REMOVAL 10 602 AIR FILTER Y i COVER ASSEMBLY REMOVAL 19 54 495 27 769 f 4 ean 19499 SPARKPLUG ie d SPARK PLUG FUL K Ji 12X 89 41 2X 77 90 p di 52991 33462 P 83067 20 863 i Ab PRIMARY AIR FILTER 13 174 YV ELEMENT REMOVAL amp CRANKSHAFT 417 59 d 16 441 d SAFETY AIR FIL
182. rom sensor to engine sensor grounds through shell see Oxygen Sensor section Condition System operates under open loop control only Until fault is detected and registered by ECU engine will run rich if oxygen sensor is shorted to ground or lean if it is shorted to battery voltage After fault is detected performance can vary depending on cause If performance is pretty good problem is probably with oxygen sensor wiring or connectors If engine is still running rich laboring short on power or lean popping or misfiring fuel mixture is suspect probably incorrect TPS initialization or low fuel pressure TPS Initialization Incorrect e Lean condition check oxygen sensor signal with VOA and see Oxygen Sensor section Engine Wiring Harness Related e Pin circuit wiring or connectors Pin 11 for 24 Pin MSE 1 0 Plastic Cased ECU Pin 20 for 32 Pin MSE 1 1 Plastic Cased ECU Low Fuel Pressure Oxygen Sensor Related e Sensor connector or wiring problem e Exhaust leak e Poor ground path to engine sensor is case grounded Poor system ground from ECU to engine causing rich running while indicating lean 24 690 02 Rev E KohlerEngines com 71 EFI SYSTEM BOSCH Code 33 Component Oxygen Sensor Fuel System Fault System too rich Temporary fuel adaptation control is at upper limit Condition Fuel Supply Related nothing lea
183. rs NOTE Cylinder heads are retained using either screws or nuts and washers on studs Do not interchange or mix components 1 Remove screws or nuts and washers securing each cylinder head Discard screws or nuts and washers once removed Do not reuse Studs if present should only be removed if damaged or if cylinder reconditioning is necessary Once removed they must be replaced 2 Mark location of push rods as either intake or exhaust and cylinder 1 or 2 Push rods should always be reinstalled in same positions 3 Carefully remove push rods cylinder heads and head gaskets 4 Remove lifters from lifter bores Use a hydraulic lifter tool Do not use a magnet to remove lifters Mark lifters by location as either intake or exhaust and cylinder 1 or 2 Hydraulic lifters should always be reinstalled in same position Inspection Check base surface of hydraulic lifters for wear or damage If lifters need to be replaced apply a liberal coating of Kohler lubricant see Tools and Aids to base of each new lifter before it is installed Bleeding Lifters To prevent a possible bent push rod or broken rocker arm it is important to bleed any excess oil out of lifters before they are installed 24 690 02 Rev E Disassembly Inspection and Service 1 Cuta 50 75 mm 2 3 in piece from end of an old push rod and chuck it in a drill press 2 Lay a rag or shop towel on table of drill press and place lifter open end up o
184. s ECV EFI 1 Remove screws securing each valve cover Note valve cover differences for proper location in reassembly Ensure any brackets removed are reassembled in same location 2 Covers should lift off without prying Remove Crankshaft Position Sensor Remove Manifold Absolute Pressure MAP Sensor 1 Remove screws securing crankshaft position sensor bracket 2 Disconnect electrical connector to crankshaft position sensor ECV EFI 1 With a screwdriver slide locking tab on electrical connector 2 Detach connector Remove screw and pull MAP sensor out of intake manifold 94 KohlerEngines com 24 690 02 Rev E Remove Fuel Injectors 1 Disconnect electrical connector 2 Remove screw and pull injector out of intake manifold for each injector 3 When removed pull metal retaining clip connecting fuel injector to fuel injector cap There may be some fuel left in line Any spilled fuel must be cleaned up immediately Remove Intake Manifold 1 Remove screw securing a ring terminal which is part of wiring hamess 2 Remove screws securing intake manifold to cylinder heads Note which screws hold wiring clamp 3 Unclasp wiring harness from clip using a screwdriver 4 Remove intake manifold and intake manifold gaskets 5 Leave wiring harness attached to manifold Remove Spark Plugs Remove spark plug from each cylinder head Remove Cylinder Heads and Hydraulic Lifte
185. s back out idle speed adjusting screw counterclockwise until throttle plates can be closed completely Write this number down for reference later 2 Disconnect Black connector from ECU but leave TPS mounted to throttle body 3 a Use an ohmmeter and connect red positive ohmmeter lead to Black pin 12 terminal and black negative ohmmeter lead to Black pin 10 terminal to test 24 690 02 Rev E EFI SYSTEM ECV b Hold throttle closed and check resistance It should be 1400 1800 O 4 Leave leads connected to pin terminals as described in step 3 Rotate throttle shaft slowly to full throttle position Monitor dial during rotation for indication of any momentary short or open circuits Note resistance at full throttle position It should be 4600 5200 O without a stop pin or 3200 4100 O with a stop pin 5 Disconnect main wiring harness connector from TPS leaving TPS assembled to throttle body Refer to Resistance Table and perform resistance checks indicated between terminals in TPS switch with throttle in positions specified If resistance values in steps 3 4 and 5 are within specifications go to step 6 If resistance values are not within specifications or a momentary short or open circuit was detected during rotation step 4 TPS needs to be replaced go to step 7 6 Check TPS circuits input ground between TPS plug and main harness connector for continuity damage etc Input pin is 12 and ground is pi
186. s Shaft Bore l D New Max Wear Limit 8 025 8 075 mm 0 3159 0 3179 in 8 088 mm 0 3184 in 6 mm Shaft New Max Wear Limit 8 mm Shaft New Max Wear Limit 6 025 6 050 mm 0 2372 0 2382 in 6 063 mm 0 2387 in 8 025 8 075 mm 0 3159 0 3179 in 8 088 mm 0 3184 in 3Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 10 KohlerEngines com 24 690 02 Rev E CLEARANCE SPECIFICATIONS Crankshaft ECV630 ECV680 ECV730 ECV749 Specifications CV26 CV735 CV745 End Play free 0 025 0 635 mm 0 001 0 025 in 0 070 0 590 mm 0 0028 0 0230 in Bore in crankcase New Max Wear Limit Bore in oil pan New Crankshaft to Sleeve Bearing oil pan Running Clearance New 40 972 40 997 mm 1 6131 1 6141 in 41 011 mm 1 6146 in 40 974 41 000 mm 1 6131 1 6141 in 0 03 0 12 mm 0 001 0 005 in 40 965 41 003 mm 1 6128 1 6143 in 41 016 mm 1 6148 in 40 987 40 974 mm 1 6136 1 6131 in 0 03 0 09 mm 0 0012 0 0035 in Crankshaft Bore oil pan to Crankshaft Running Clearance New 0 039 0 087 mm 0 0015 0 0034 in 0 039 0 074 mm 0 0015 0 0029 in Flywheel End Main Bearing Journal O D New O D Max Wear Limit Max Taper Limit Max Out of Round Limit Oil Pan End Main Bearing Journal O D New O D Max Wear Limit Max Taper Max Out of Rou
187. s and Fasteners Assembled Into Cast Iron or Steel Grade 2 or 5 Fasteners Into Aluminum Size Grade 2 Grade 5 Grade 8 Q Tightening Torque N m in Ib 20 8 32 2 3 20 2 8 25 2 3 20 10 24 3 6 32 4 5 40 3 6 32 10 32 3 6 32 4 5 40 1 4 20 7 9 70 13 0 115 18 7 165 7 9 70 1 4 28 9 6 85 15 8 140 22 6 200 5 16 18 17 0 150 28 3 250 39 6 350 17 0 150 5 16 24 18 7 165 30 5 270 3 8 16 29 4 260 3 8 24 33 9 300 Tightening Torque N m ft Ib 20 5 16 24 40 7 30 3 8 16 47 5 35 67 8 50 3 8 24 54 2 40 81 4 60 71 16 14 47 5 35 74 6 55 108 5 80 7 16 20 61 0 45 101 7 75 142 5 105 1 2 13 67 8 50 108 5 80 155 9 115 1 2 20 94 9 70 142 4 105 223 7 165 9 16 12 101 7 75 169 5 125 237 3 175 9 16 18 135 6 100 223 7 165 311 9 230 5 8 11 149 5 110 244 1 180 352 6 260 5 8 18 189 8 140 311 9 230 447 5 330 3 4 10 199 3 147 332 2 245 474 6 350 3 4 16 271 2 200 440 7 325 637 3 470 Metric Fastener Torque Recommendations for Standard Applications Property Class Noncritical Size fo Aluminum Tightening Torque N m in Ib 10 M4 1 2 11 1 7 15 2 9 26 4 1 36 5 0 44 2 0 18 M5 2 5 22 3 2 28 5 8 51 8 1 72 9 7 86 4 0 35 M6 4 3 38 5 7 50 9 9 88 14 0 124 16 5 146 6 8 60 M8 10 5 93 13 6 120 24 4 216 33
188. s mounting oil cooler to blower housing then remove cooler lines and filter adapter as an assembly Remove Muffler Remove exhaust system and attaching hardware from engine On engines equipped with a port liner remove it now Remove Air Cleaner Assembly Heavy Duty Air Cleaner 1 Remove nuts securing air cleaner to mounting studs 2 Remove screws securing air cleaner assembly to mounting bracket and remove air cleaner assembly Low Profile Air Cleaner Optional 1 Loosen retaining knob and remove cover 2 Remove wing nut from element cover 3 Remove element cover element and precleaner 4 Remove nuts securing base Additional screws must be removed from lower air cleaner support bracket 5 Remove base 90 KohlerEngines com Remove governor lever spring Remove screws fastening throttle panel and remove panel from cylinder heads 24 690 02 Rev E Disassembly Inspection and Service External Governor Control ECV EFI on Speed Control Cable Clamp Throttle Actuator A Bracket C Screw Lever bottom E Spring Washer Throne poe Lever G Flat Washer Nut Return Spring Remove External Governor Controls 1 Disconnect governor spring attached to governor lever Note hole location for reassembly 2 Disconnect throttle linkage spring Remove throttle linkage bushing and thr
189. shaft from inside of crankcase 24 690 02 Rev E Oil pump is mounted inside oil pan If service was required and oil pump was removed refer to assembly procedures under Oil Pump Assembly in Disassembly Inspection and Service Governor Gear Assembly Governor gear assembly is located inside oil pan If service was required and governor was removed refer to assembly procedures under Disassembly Inspection and Service Install Oil Pan Oil Seal Oil Seal Details A Oil Seal B 6 5 mm 0 255 in Check to make sure that there are no nicks or burrs in crankshaft bore of oil pan 2 Apply a light coat of engine oil to outside diameter of oil seal 3 Drive oil seal into oil pan using a seal driver Make sure oil seal is installed straight and true in bore to depth shown KohlerEngines com 105 Reassembly Install Oil Pan Assembly Oil Pan Sealant Pattern RTV Must Be All Apply 1 5 mm 1 16 A B Around O ring in bead of sealant Groove C Point B D Point A Fill groove between E points C and D with RTV Most engines use an oil pan gasket Optionally RTV sealant is used as a gasket between oil pan and crankcase When assembling oil pan only use a gasket if a gasket was removed Likewise if RTV was used only replace with RTV Do Not use both Refer to Tools and Aids for a listing of approved sealants Always use
190. sing be mounted vertically with the sire bundle down or horizontally with the keep oper maintain the the dE lore is to mal Opera resistive spork plug with either a resistive spark plug sire or boot must be used to prevent electricel system tain EEG Be Attached to engine block close to the col 24 690 02 Rev E EFI SYSTEM BOSCH 32 Pin MSE 1 1 Plastic Cased ECU Systems Pin Component 1 Permanent Battery Voltage 2 Switched Battery Voltage 3 TPS Set Auto Learn Initialization Terminal 4 Throttle Position Sensor TPS and Temperature Sensor Ground 5 Not Used 6 Oil Temperature Sensor Input 7 Not Used 8 Throttle Position Sensor TPS Input 9 Speed Sensor Input 10 Speed Sensor Ground 11 Not Used 12 Not Used 13 Not Used 14 Injector 1 Output 15 Injector 2 Output 16 Not Used 17 Diagnostic Line 18 Throttle Position Sensor Supply Voltage 19 Battery Ground 20 Oxygen Sensor Input 21 Battery Ground Secondary 22 Not Used 23 Not Used 24 Not Used 25 Safety Switch Input 26 Not Used 27 Not Used 28 Main Relay Output 29 Malfunction Indicator Light MIL 30 Ignition Coil 1 Output 31 Ignition Coil 2 Output 32 Not Used o wd AN O oc K o N o o o o o o o o o o o o o o o o o O O0 0 o O 00 00 0000 0 24 690 02 Rev E KohlerEngines com 65 EFI SYSTEM BOSCH rang Carm p or ge b amm rid quen rers 1t ud a p ond pm v tu Rope HL poenibai v
191. sing screws Torque screws to 9 2 N m 81 in Ib N oa E Install External Governor Controls ECV EFI Speed Control A Bracket B Cable Clamp C Screw D Throttle Actuator Lever bottom E Spring Washer F Throsie Lover G Flat Washer H Nut l Return Spring 1 Install governor lever onto governor cross shaft 2 Make sure throttle linkage linkage spring black linkage bushing are connected to governor lever and to throttle lever on throttle body Install Throttle Control Panel Assemble Top Mount Control Panel 1 Install lower support control bracket with throttle control shaft 2 Install top mount control panel over throttle control shaft Secure control panel to blower housing with screws 3 Assemble throttle control lever and applicable hardware to throttle control shaft 116 KohlerEngines com 24 690 02 Rev E 4 Attach governor spring to previously marked hole on governor lever Install Bottom Mount Control Panel If Equipped Throttle Control Bracket Detail NOTE To identify various parts and assembly of throttle control panel refer to External Governor Control Components lt Install bottom control panel and air cleaner support bracket if used to cylinder heads using screws Torque screws to 10 7 N m 95 in Ib into new holes or 7 3 N m 65 in Ib into used holes 2 Connect governor spring from thr
192. sor Related e Sensor wiring or connection Engine Wiring Harness Related e Pin circuits Black 10 and Black 14 maybe damaged or routed near noisy signal coils stator etc e ECU to harness connection problem 24 690 02 Rev E KohlerEngines com 41 EFI SYSTEM ECV Code 0123 Code 0171 Component Throttle Position Sensor TPS Component Fuel System Fault TPS Circuit High Voltage Fault Maximum adaptation limit exceeded Condition Shorted connection or faulty sensor Condition Fuel inlet screen filter plugged low Conclusion TPS Sensor Related pressure at high pressure fuel line TPS e Sensor connector or wiring malfunction shorted connection faulty e Sensor output affected or disrupted by sensor low fuel or wrong fuel type dirt grease oil wear Conclusion Oxygen Sensor Related e Sensor loose on throttle body manifold e Corrosion or poor connection e Sensor contaminated or damaged Throttle Body Related e Air leak into exhaust e Throttle shaft or bearings worn e Poor ground path damaged e Pin circuit wiring or connectors ECU Black pin 10 or Black pin 17 Engine Wiring Harness Related e ECU pins Black 10 12 and 16 TPS Sensor Related damaged wiring connectors e Throttle plate position incorrect during e ECU pins Black 10 12 and 16 routed Learn procedure near noisy electrical signal coils e TPS problem or malfunc
193. stator aligning mounting holes so that leads are at bottom towards crankcase Install and torque screws to 6 2 N m 55 in Ib for new holes or 4 0 N m 35 in Ib for used holes Route stator leads in crankcase channel then install backing plate Secure with screws Torque screws 10 7 N m 95 in Ib for new holes or 7 3 N m 65 in Ib for used holes 24 690 02 Rev E Install Flywheel A CAUTION Damaging Crankshaft and Flywheel Can cause personal injury Js CI Using improper procedures can lead to broken fragments Broken fragments could be thrown from engine Always observe and use precautions and procedures when installing flywheel Flywheel Components e oll Oa eh UH OI T rA JE c Au U f i NS Sc A Ok OO ASYN a MIN A lt ji k 17 4 B A Flywheel Fan B Flywheel C Stator D Backing Plate 24 690 02 Rev E Reassembly NOTE Before installing flywheel make sure crankshaft taper and flywheel hub are clean dry and completely free of any lubricants Presence of lubricants can cause flywheel to be over stressed and damaged when screw is torqued to specifications NOTE Make sure flywheel key is installed properly in keyway Flywheel can become cracked or damaged if key is not properly installed 1 Install woodruff key into keyway of crankshaft Make sure that key is properly seated and parallel with shaft taper 2 Insta
194. t Control Panel Only clean parts can be accurately inspected and gauged for wear or damage There are many T commercially available cleaners that will quickly remove grease oil and grime from engine parts When such a 2 cleaner is used follow manufacturer s instructions and safety precautions carefully Make sure all traces of cleaner are removed before engine is reassembled and placed into operation Even small amounts of these cleaners can quickly break down 3 Remove throttle control shaft nut on top of throttle shaft and remove throttle control lever and spring Remove screws fastening control panel and remove panel from blower housing Remove lower throttle control bracket from cylinder head Remove Bottom Mount Control Panel if equipped lubricating properties of engine oil 1 Disconnect Spark Plug Leads 2 NOTE Pull on boot only to prevent damage to spark plug lead Disconnect leads from spark plugs Drain Oil from Crankcase and Remove Oil Filter NOTE Some models are equipped with an oil drain valve 1 Remove oil fill cap dipstick and 1 oil drain plug 2 Allow ample time for oil to drain from crankcase and oil filter 3 Remove mounting screw and detatch oil fill tube 4 Remove and discard oil filter Remove Oil Cooler 1 Usean 8 mm Allen wrench to remove oil filter threaded nipple 2 Separate filter adapter from oil pan leaving oil lines attached Remove screw
195. t excess oil 4 Reinstall precleaner over paper element Paper Element 1 Clean area around element Remove wing nut element cover and paper element with precleaner 2 Separate precleaner from element service precleaner and replace paper element 3 Check condition of rubber seal and replace if necessary 4 Install new paper element on base install precleaner over paper element reinstall element cover and secure with wing nut Reinstall air cleaner cover and secure with knob Heavy Duty 1 Unhook retaining clips and remove end cap s 2 Check and clean inlet screen if equipped 3 Pull air cleaner element out of housing and replace Check condition of inner element replace when dirty 4 Check all parts for wear cracks or damage and that ejector area is clean 5 Install new element s 6 Reinstall end cap s with dust ejector valve screen down secure with retaining clips BREATHER TUBE Ensure sure both ends of breather tube are properly connected AIR COOLING WARNING zt Hot Parts can cause severe burns wills Do not touch engine while operating or just after stopping Never operate engine with heat shields or guards removed Proper cooling is essential To prevent over heating clean screens cooling fins and other external surfaces of engine Avoid spraying water at wiring harness or any electrical components Refer to Maintenance Schedule 24 690 02 Rev
196. t manufacturer s recommendation 24 690 02 Rev E EFI SYSTEM BOSCH For starting and warm up ECU will adjust fuel and ignition timing based upon ambient temperature engine temperature and loads present In cold conditions idle speed will probably be higher than normal for a few moments Under other conditions idle speed may actually start lower than normal but gradually increase to established setting as operation continues Do not attempt to circumvent this warm up period or readjust idle speed during this time Engine must be completely warmed up in closed loop operating mode for accurate idle adjustment IMPORTANT NOTES e Cleanliness is essential and must be maintained at all times when servicing or working on EFI system Dirt even in small quantities can cause significant problems Clean any joint or fitting with parts cleaning solvent before opening to prevent dirt from entering system Always depressurize fuel system through fuel connector on fuel pump module before disconnecting or servicing any fuel system components Never attempt to service any fuel system component while engine is running or ignition switch is ON Do not use compressed air if system is open Cover any parts removed and wrap any open joints with plastic if they will remain open for any length of time New parts should be removed from their protective packaging just prior to installation Avoid direct water or spray contact with system compone
197. t of ECU KohlerEngines com 27 EFI SYSTEM ECV Never attempt to disassemble ECU It is sealed to prevent damage to internal components Warranty is void if case is opened or tampered with in any way All operating and control functions within ECU are preset No internal servicing or readjustment may be performed If a problem is encountered and you determine ECU to be faulty contact your source of supply ECU pins are coated at factory with a thin layer of electrical grease to prevent fretting and corrosion Do not attempt to remove grease from ECU pins Relationship between ECU and throttle position sensor TPS is very critical to proper system operation If TPS or ECU is changed or mounting position of TPS is altered appropriate TPS Learn Procedure must be performed to restore synchronization Any service to ECU TPS Throttle Body including idle speed increase over 300 RPM or fuel pump module replacement should include ECU Reset This will clear all trouble codes all closed loop learned offsets all max values and all timers besides permanent hour meter This system will NOT reset when battery is disconnected ECU Reset Procedure 1 Turn key OFF 2 Install Red wire jumper from Kohler EFI service kit on to service port connect white wire to black wire in 4 way diagnostic port 3 Turn key ON then OFF and count 10 seconds 4 Turn key ON then OFF and count to 10 seconds a second time 5 Remove jumper
198. t overlaps blower housing If engine has a radiator type oil cooler mounted to blower housing remove oil cooler mounting screws Remove blower housing mounting screws Note location of plated silver screw attaching rectifier regulator ground lead Remove blower housing Thoroughly clean area around and including throttle body manifold and injectors Disconnect throttle linkage and damper spring from t throttle lever Disconnect TPS lead from harness Remove manifold mounting bolts and separate throttle body manifold from engine leaving TPS fuel rail air baffle injectors and line connections intact Discard old gaskets Position manifold assembly over an appropriate container and turn key switch ON to activate fuel pump and pressurize system Do not turn switch to start position KohlerEngines com 57 EFI SYSTEM BOSCH 12 If either injector exhibits leakage of more than two to four drops per minute from tip or shows any sign of leakage around outer shell turn ignition switch off and replace injector as follows 13 Depressurize fuel system following procedure in fuel warning on page Remove fuel rail mounting screws 14 Clean any dirt accumulation from sealing mounting area of faulty injector s and disconnect electrical connector s 15 Pull retaining clip off top of injector s Disconnect fuel rail and remove injector s from manifold 16 Reverse appropriate procedures to install new injector s and reass
199. t washer from inside commutator end 6 Remove frame from armature and drive end cap 7 Remove rubber grommet and backing plate from end cap 8 Take out drive lever and pull armature out of drive end cap 9 Remove thrust washer from armature shaft 10 Push stop collar down to expose retaining ring 11 Remove retainer from armature shaft Save stop collar 12 Remove drive pinion assembly from armature 13 Clean parts as required Inspection Check drive pinion and inspect following areas e Pinion teeth for abnormal wear or damage e Surface between pinion and clutch mechanism for nicks or irregularities which could cause seal damage e Check drive clutch by holding clutch housing and rotating pinion Pinion should rotate in only 1 direction Brushes and Springs Detail A Wear Limit Length Inspect both springs and brushes for wear fatigue or damage Measure length of each brush Minimum length for each brush is 7 6 mm 0 300 in Replace brushes if they are worn undersize or condition is questionable 24 690 02 Rev E Armature Components and Details A Commutator O D B Mica Insulation Insulation Check D Armature Coil Continuity Check 4 Shi Clean and inspect commutator outer surface Mica insulation must be lower than commutator bars undercut to ensure proper operation of commutator Use an ohmmeter
200. tem Incorrect adjustment can result in overspeed loss of power lack of response or inadequate load compensation If you encounter any of these symptoms and suspect them to be related to governor setting following should be used to check and or adjust governor and throttle linkage If governor throttle components are all intact but you think there may be a problem with adjustment follow Procedure A to check setting If governor lever was loosened or removed go immediately to Procedure B to perform initial adjustment A Checking Initial Adjustment 1 Unsnap plastic linkage bushing attaching throttle linkage to governor lever Unhook damper spring from lever separate linkage from bushing and remove bushing from lever Mark hole position and unhook governor spring from governor lever 2 Check if engine has a high speed throttle stop screw installed in manifold casting boss a On engines without a stop screw pivot throttle shaft and plate assembly into FULL THROTTLE position Insert a 1 52 mm 0 060 in feeler gauge between rear tang of throttle shaft plate and underside of manifold boss Use a locking pliers needle nose works best to temporarily clamp parts in this position b Onengines with a stop screw pivot throttle shaft and plate into FULL THROTTLE position so tang of throttle shaft plate is against end of high speed stop screw Temporarily clamp in this position 3 Rotate governor lever and shaft countercl
201. tention and if cylinder piston rings or valves are worn Individual component available Design Technology Inc Adapter 12 mm x 14 mm Required for leakdown test on XT 6 engines DTI 731 03 Dealer Tool Kit Domestic Kohler 25 761 39 S Complete kit of Kohler required tools Components of 25 761 39 S Ignition System Tester Kohler 25 455 01 S Cylinder Leakdown Tester Kohler 25 761 05 S Oil Pressure Test Kit Kohler 25 761 06 S Rectifier Regulator Tester 120 V AC 60Hz Kohler 25 761 20 8 Dealer Tool Kit International Kohler 25 761 42 S Complete kit of Kohler required tools Components of 25 761 42 S Ignition System Tester Kohler 25 455 01 S Cylinder Leakdown Tester Kohler 25 761 05 S Oil Pressure Test Kit Kohler 25 761 06 S Rectifier Regulator Tester 240 V AC 50Hz Kohler 25 761 41 S Digital Vacuum Pressure Tester Design Technology Inc For checking crankcase vacuum DTI 721 01 Individual component available Design Technology Inc Rubber Adapter Plug DTI 721 10 Electronic Fuel Injection EFI Diagnostic Software Kohler 25 761 23 S For Laptop or Desktop PC EFI Service Kit Kohler 24 761 01 S For troubleshooting and setting up an EFI engine Components of 24 761 01 S Design Technology Inc Fuel Pressure Tester DTI 019 Noid Light DTI 021 90 Adapter DTI 023 In line T Fitting DTI 035 Code Plug Red Wire DTI 027 Code Plug Blue Wire DTI 029 Shrader Valve Adapter Hose DTI 037 Flywheel Holding Tool CS SE To
202. ting from blocked cooling fins or from inadequate or contaminated lubrication If cylinder bore is badly scored excessively worn tapered or out of round resizing is necessary Use an inside micrometer to determine amount of wear refer to Specifications then select nearest suitable oversize of either 0 25 mm 0 010 in or 0 50 mm 0 020 in Resizing to one of these oversizes will allow usage of available oversize piston and ring assemblies First resize using a boring bar then use these following procedures for honing cylinder 24 690 02 Rev E Honing Detail A 23 33 Crosshatch NOTE Kohler pistons are custom machined to exacting tolerances When oversizing a cylinder it should be machined exactly 0 25 mm 0 010 in or 0 50 mm 0 020 in over new diameter Specifications Corresponding oversize Kohler replacement piston will then fit correctly While most commercially available cylinder hones can be used with either portable drills or drill presses use of a low speed drill press is preferred as it facilitates more accurate alignment of bore in relation to crankshaft crossbore Honing is best accomplished at a drill speed of about 250 RPM and 60 strokes per minute After installing coarse stones in hone proceed as follows 1 Lower hone into bore and after centering adjust so stones are in contact with cylinder wall Use of a commercial cutting cooling agent is recommended 2 With lower ed
203. tion alternator e doa beue volt source from ECU Engine Wiring Harness Related n vari i b e Difference in voltage between sensed 2 nese LONNECHON problem voltage and actual sensor voltage e Problem in wiring harness Code 0131 e ECU to harness connection problem Component Oxygen Sensor Susi Betteng Tr ystems Relate Fault EIN Low Voltage e Ignition spark plug plug wire ignition Condition Open connection broken wire or faulty coil sensor e Fuel fuel type quality injector fuel Conclusion Oxygen Sensor Related pressure too low fuel pump module or e Sensor connector or wiring problem lift pump m e Sensor contaminated corroded or e Combustion air air cleaner dirty damaged restricted intake leak throttle bores e Poor ground path e Base engine problem rings valves e Pin circuit wiring or connectors e Exhaust system leak muffler flange ECU Black pin 10 or 17 oxygen sensor mounting boss etc e Fuel in crankcase oil TPS Learn Procedure Incorrect e Lean condition check oxygen sensor signal with VOA and see Oxygen Sensor section Engine wiring harness related such as a cut wire broken or pinched Code 0132 Component Oxygen Sensor Fault O28 1 Circuit High Voltage Condition Shorted connection or faulty sensor Conclusion Oxygen Sensor Related e Sensor connector or wiring problem e Sensor contaminated or damaged e Poor ground path e Pin circuit wiring or connectors ECU Black pin 10 o
204. tions that intermittently ground ignition kill circuit e Low compression e Quality of fuel dirt water stale mixture e Weak spark 18 KohlerEngines com e Cooling fan broken e Excessive engine load e Fan belt failed off e Faulty carburetor e High crankcase oil level e Lean fuel mixture e Low cooling system fluid level e Low crankcase oil level e Radiator and or cooling system components clogged restricted or leaking e Water pump belt failed broken e Water pump malfunction Engine Knocks e Excessive engine load e Hydraulic lifter malfunction e Incorrect oil viscosity type e Internal wear or damage e Low crankcase oil level e Quality of fuel dirt water stale mixture 24 690 02 Rev E Engine Loses Power e Dirty air cleaner element e Engine overheated e Excessive engine load e Restricted exhaust e Faulty spark plug s e High crankcase oil level e Incorrect governor setting e Low battery e Low compression e Low crankcase oil level e Quality of fuel dirt water stale mixture Engine Uses Excessive Amount of Oil e Loose or improperly torqued fasteners e Blown head gasket overheated e Breather reed broken e Clogged broken or inoperative crankcase breather e Crankcase overfilled e Incorrect oil viscosity type e Worn cylinder bore e Worn or broken piston rings e Worn valve stems valve guides Oil Leaks from Oil Seals Gaskets
205. to ambient air When oxygen concentration on one side of tip is different than that of other side a voltage signal between 0 2 and 1 0 volts is generated between electrodes and sent to ECU Voltage signal tells ECU if engine is straying from ideal 14 7 1 fuel mixture and ECU then adjusts injector pulse accordingly Oxygen sensor can function only after being heated by exhaust temperatures to a minimum of 375 C 709 F A cold oxygen sensor will require approximately 1 2 minutes at moderate engine load to warm sufficiently to generate a voltage signal Proper grounding is also critical Oxygen sensor grounds through metal shell So a good solid unbroken ground path back through exhaust system components engine and wiring harness is required Any disruption or break in ground circuit can affect output signal and trigger misleading fault codes Keep that in mind when doing any troubleshooting associated with oxygen sensor Oxygen sensor can also be contaminated by leaded fuel certain RTV and or other silicone compounds carburetor cleaners etc Use only those products indicated as O Sensor Safe Electrical relay is used to supply power to injectors coil and fuel pump When key switch is turned ON and all safety switch requirements met relay provides 12 volts to fuel pump circuit injectors and ignition coils Fuel pump circuit is continuously grounded so pump is immediately activated and pressurizes system Activation of igniti
206. uel pump will run for about three seconds and stop Turn Switch off and back on to restart fuel pump Repeat this procedure until fuel pump has cycled five times then start engine 3 System can also be primed similar to relieving pressure a Connect pressure gauge as described above for relieving fuel pressure Depress and hold release button and crank engine until air is purged and fuel is visible in discharge tube If fuel is not visible after 10 seconds stop cranking and allow starter to cool for 60 seconds Priming Without a Test Valve in Fuel Rail NOTE Number of cranking intervals necessary will depend on individual system design and or when system has been disassembled 1 Crank engine in 10 15 second intervals allowing a 60 second cool down period between cranking intervals until engine starts ELECTRICAL COMPONENTS Two different styles of ECU s have been utilized in EFI production Both styles have plastic cases but are smaller in overall size These have either a 24 pin or 32 pin connector block and identified as MSE 1 0 or MSE 1 1 respectively Basic function and operating control remains same between three however due to differences in internal circuitry as well as wiring harness none of ECU s are interchangeable Certain individual service troubleshooting procedures also apply where applicable they are covered individually as 24 Pin MSE 1 0 Plastic Cased ECU or 32 Pin MSE 1 1 Plastic Cased ECU
207. ulty sensor or Fault TPS Circuit Low Voltage or Open shorted wire Condition Open connection broken wire or faulty Conclusion Temperature Sensor Related sensor e Sensor wiring or connection Conclusion TPS Related e TPS bad or worn internally Engine Wiring Harness Related e Pin circuits Black 10 and Black 8 may Engine Wiring Harness Related be damaged or routed near noisy e Broken or shorted wire in harness signal coils alternator etc ECU Black pin 10 to TPS pin 1 e ECU to harness connection problem ECU Black pin 12 to TPS pin 3 ECU Black pin 16 to TPS pin 2 GE Throttle Body Related rottle Body Relate Component Intake Air Temperature Sensor e Throttle shaft inside TPS worn broken Fault Intake Air Temperature Sensor Circuit or damaged High Voltage or Open e Throttle plate loose or misaligned Condition Shorted connection faulty sensor broken e Throttle plate bent or damaged wire or connection allowing extra airflow past or restricting Conclusion Temperature Sensor Related movement e Sensor wiring or connection ECU Related _ Engine Wiring Harness Related bi e KE voltage or ground to e Pin circuits ECU Black pin 10 and 8 e TPS REPE Gett may be damaged 9 RE e ECU to harness connection problem or broken wire Code 0117 Component Coolant Oil Sensor Fault Coolant Oil Temperature Sensor Circuit Low Voltage Condition Shorted connection faulty sensor or shorted wire Conclusion Temperature Sen
208. urge port remains unused port must remain capped to prevent dirt from entering engine EFI engines have no carburetor so throttle function regulate incoming combustion airflow is achieved with a throttle valve in a separate throttle body attached to intake manifold Throttle body intake manifold provides mounting for fuel injectors throttle position sensor MAP sensor intake air temperature sensor high pressure fuel line idle speed screw and air cleaner assembly Idle speed is only adjustment that may be performed on EFI system Standard idle speed setting for EFI engines is 1500 RPM but certain applications might require a different setting Check equipment manufacturer s recommendation For starting and warm up ECU will adjust fuel and ignition timing based upon ambient temperature engine temperature and loads present In cold conditions idle speed will probably be different than normal for a few moments Under other conditions idle speed may actually start lower than normal but gradually increase to established setting as operation continues Do not attempt to circumvent this warm up period or readjust idle speed during this time Engine must be completely warmed up in closed loop operating mode for accurate idle adjustment IMPORTANT NOTES Cleanliness is essential and must be maintained at all times when servicing or working on EFI system Dirt even in small quantities can cause significant problems Clean
209. ut as required to obtain 1500 RPM or idle speed specified by equipment manufacturer 4 Idle speed adjustment can affect high idle speed setting Move throttle control to full throttle position and check high idle speed Adjust as necessary to 3750 RPM or speed specified by equipment manufacturer Idle Speed Screw Dampening Spring Idle Speed Screw Details 1 3 mm 0 039 0 117 in Exposed A Dampening Spring B Length Off End Of Some Models Adjustment Screw C Idle Speed Screw A small dampening spring is attached to end of idle speed screw of some EFI engines to help stabilize no load operating speeds Idle speed adjustment procedure remains same for engines with or without a dampening spring Typically no periodic servicing is necessary in this area If however removal replacement of dampening spring is required reinstall it as follows 1 Thread spring onto end of idle screw leaving 1 3 mm 0 039 0 117 in of spring extending beyond end of idle speed screw 2 Secure spring onto screw with a small amount of Permabond LM 737 or equivalent Loctite adhesive Do not get any adhesive on free coils of spring 3 Start engine and recheck idle speed settings after sufficient warm up Readjust as required 60 KohlerEngines com Initial Governor Adjustment Initial governor adjustment is especially critical on EFI engines because of accuracy and sensitivity of electronic control sys
210. vehicle connection will have a tan wire which is ground for MIL Either incandescent or LED type bulbs can be used for MIL as long as they do not draw more than 0 1 amps Bulb needs to be rated at 1 4 Watts or less or needs to have a total resistance of 140 O or more LEDs typically draw less than 0 03 amps Attach 12 volts to positive terminal of bulb and attach ground terminal of bulb to tan wire 40 KohlerEngines com Diagnostic Code Summary Code 0031 Component Oxygen Sensor Heater Fault O2S Heater Circuit High Voltage Condition System voltage too high shorted connection or faulty sensor Conclusion Oxygen Sensor Related e Sensor connector or wiring problem e Sensor damaged e Pin circuit wiring or connectors at Black T ECU Related e ECU to harness connection problem Code 0032 Component Oxygen Sensor Heater Fault O2S Heater Circuit Low Voltage Condition System voltage too low open connection or faulty sensor Conclusion Engine Wiring Harness Related e Pin circuit wiring or connectors ECU black pin 7 or broken wire Oxygen Sensor Related e Sensor connector or wiring problem Poor system ground from ECU to engine or battery to engine Code 0107 Component Manifold Absolute Pressure Sensor Fault MAP Circuit Low Voltage or Open Condition Intake manifold leak open connection or faulty sensor Conclusion MAP Sensor Relate
211. very One second pause of fuel at system operating pressure of 39 psi 3 If an engine starts hard or turns over but will not start it may p A Xt indicate a problem with EFI fuel system A quick test will verify if system is operating 1 Disconnect and ground spark plug leads Three second pause 2 Complete all safety interlock requirements and crank engine for approximately 3 seconds It Lt E It SS Et 6 3 Remove spark plugs and check for fuel at tips One second pause End Code 61 a If there is fuel at tips of spark plugs fuel pump and i 1 injectors are operating b If there is no fuel at tips of spark plugs check following 1 Make sure fuel tank contains clean fresh proper fuel 2 Make sure that vent in fuel tank is open 3 Make sure fuel tank valve if equipped is fully opened 4 Make sure battery is supplying proper voltage 5 Check that fuses are good and that no electrical or fuel line connections are damaged or broken 6 Test fuel pump module operation as described earlier under Fuel Pump Diagnostic Fault Code Summary Fault Code Connection or Failure Description 0031 Oxygen Sensor Heater Circuit High Voltage 0032 Oxygen Sensor Heater Circuit Low Voltage 0107 Manifold Absolute Pressure Sensor Circuit Low Voltage or Open 0108 Manifold Absolute Pressure Sensor Circuit High Voltage 0112 Intake Air Temperature Sensor Circuit Low Voltage 0113 Intake Air Temperature Sensor Circuit High Voltage or Open 0117 Coolant Oi
212. volt test lead to flat spade S start terminal on solenoid and other lead to body or mounting surface of solenoid 2 Manually push plunger IN and check if coil holds plunger retracted Do not allow test leads to remain connected to solenoid for a prolonged period of time Continuity 1 Use an ohmmeter set to audible or Rx2K scale and connect 2 ohmmeter leads to 2 large post terminals 2 Perform preceding solenoid hold in coil function test and check for continuity Meter should indicate continuity Repeat test several times Condition Conclusion Solenoid fails to activate Replace solenoid No continuity is indicated Plunger fails to stay retracted 88 KohlerEngines com 24 690 02 Rev E death xf Be before servicing Accidental Starts can cause severe injury or Disconnect and ground spark plug lead s Disassembly Inspection and Service Before working on engine or equipment disable engine as follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery External Engine Components B C200 A Debris Screen Guard Debris Screen Outer Baffle Rectifier Regulator Oil Temperature E Inner Baffle Oil Sentry Sensor Breather Cover I Breather Cover Gasket 24 690 02 Rev E KohlerEngines com 89 Disassembly Inspection and Service Clean all parts thoroughly as engine is disassembled Remove Top Moun
213. ws and 9 9 N m 88 in Ib Spacers Yellow or Brown O Ring Style Cover w Integral Metal Spacers 6 2 N m 55 in Ib CLEARANCE SPECIFICATIONS ECV630 ECV680 ECV730 ECV749 CV26 CV735 CV745 Camshaft End Play with shim 0 051 0 381 mm 0 002 0 015 in 0 076 0 127 mm 0 0030 0 0050 in Running Clearance 0 025 0 105 mm 0 001 0 004 in 0 025 0 063mm 0 0010 0 0025 in Bore I D New Max Wear Limit 20 000 20 025 mm 0 7874 0 7884 in 20 038 mm 0 7889 in 20 000 20 025 mm 0 7874 0 7884 in 20 038 mm 0 7889 in Bearing Surface O D New Max Wear Limit 19 920 19 975 mm 0 7843 0 7864 in 19 914 mm 0 7840 in 19 962 19 975 mm 0 7859 0 7864 in 19 959 mm 0 7858 in Connecting Rod Connecting Rod to Crankpin Running Clearance 21 C 70 F New Max Wear Limit 0 043 0 073 mm 0 0017 0 0029 in 0 088 mm 0 0035 in 0 030 0 055 mm 0 0012 0 0022 in 0 070 mm 0 0028 in Connecting Rod to Crankpin Side Clearance 0 26 0 63 mm 0 0102 0 0248 in 0 26 0 63 mm 0 0102 0 0248 in Connecting Rod to Piston Pin Running Clearance 21 C 70 F 0 015 0 028 mm 0 0006 0 0011 in 0 015 0 028 mm 0 0006 0 0011 in Piston Pin End LD 21 C 70 F New Max Wear Limit 17 015 17 023 mm 0 6699 0 6702 in 17 036 mm 0 6707 in 17 015 17 023 mm 0 6699 0 6702 in 17 036 mm 0 6707 in Crankcase Governor Cros
214. xhaust Recondition piston rings cylinder bore valves and valves guides Check exhaust screen spark arrestor if equipped Clean or replace as needed Repair or replace any other damaged restricted muffler or exhaust system parts 20 KohlerEngines com 24 690 02 Rev E Troubleshooting COMPRESSION TEST For Command Twins A compression test is best performed on a warm engine Clean any dirt or debris away from base of spark plug s before removing them Be sure choke is off and throttle is wide open during test Compression should be at least 160 psi and should not vary more than 15 between cylinders All other models These engines are equipped with an automatic compression release ACR mechanism It is difficult to obtain an accurate compression reading because of ACR mechanism As an alternative use cylinder leakdown test described below CYLINDER LEAKDOWN TEST A cylinder leakdown test can be a valuable alternative to a compression test By pressurizing combustion chamber from an external air source you can determine if valves or rings are leaking and how badly Cylinder leakdown tester is a relatively simple inexpensive leakdown tester for small engines This tester includes a quick connect for attaching adapter hose and a holding tool 1 Run engine for 3 5 minutes to warm it up 2 Remove spark plug s and air filter from engine 3 Rotate crankshaft until piston of cylinder being tested is
215. y spbu at nap pojamod e sjozuo UIS Uou Ou H Ir eo wejsks pue 18 pue o og og 5 212 SAP 10 enj e uaewjeq e20919 4p jU amp AeJd OJ Jp jueuno tuejsks jo s5eipjeDa Jeujo u2ee jo A Z OF ILE uawas Pa L Ar pue Z Lf SO v Sina LO aBeyo au Z Burueis Bump josey 153 waned oi vojysod uru gut ci peis ouy woy dams SL VY OUJ se Z Lr pue Gg r SINI o gen juejsuo02 WPP mu YMS uorub ou p EE amos 20108 Ibn bd to dz to dz sv 3 F S o oe lt X ai S N lt 2 c COVA NNN ONNOHO ON e sg 4 sgr s zi 1w od 62 zi d EEE EE Self sz 1r HALAS AL34VS D I FEI AYBLLVE v BLON SNIONnONO _ 33S ONNOYD AN3LLVB OH ey 24 690 02 Rev E 6 ON 310N 1v33N35 33S KohlerEngines com 66 Fuel System EFI SYSTEM BOSCH Fault Codes A WARNING Fuel System Under Pressure Fuel system operates under high pressure System pressure must be relieved through test valve in fuel rail prior to servicing or removing any fuel system components Do not smoke or work near heaters or other fire hazards Have a fire extinguisher handy and work only in a well ventilated area Function of fuel system is to provide sufficient delivery of fuel at system operating pressure of 39 psi 3 If an engine starts hard or turns over but will not start it may indicate a problem with EFI fuel system A quick test will verify if system is operating 1 Disconnect an
216. y Required Above 32 F 0 C 200 cca minimum O F to 32 F 18 C to 0 C 250 cca minimum 5 F to O F 21 C to 18 C 300 cca minimum 10 F 23 C or below 400 cca minimum If battery charge is insufficient to turn over engine recharge battery Battery Maintenance Regular maintenance is necessary to prolong battery life Battery Test To test battery follow manufacturer s instructions 24 690 02 Rev E KohlerEngines com 81 Electrical System BATTERY CHARGING SYSTEM NOTE Observe following guidelines to avoid damage to the electrical system and components e Make sure battery polarity is correct A negative ground system is used e Disconnect rectifier regulator plug and or wiring harness plug before doing any electric welding on equipment powered by engine Also disconnect all other electrical accessories in common ground with engine e Prevent stator AC leads from touching or shorting while engine is running This could damage stator These engines are equipped with a 20 or 25 amp regulated charging system 20 25 Amp Regulated Charging System A Battery B Starter C Fuse D Rectifier Regulator Flywheel Stator E Connector Block Assembly Stator Stator is mounted on crankcase behind flywheel Follow procedures in Disassembly and Reassembly if stator
217. y switch and displayed as blinks or flashes of MIL Access codes as follows 1 Check that battery voltage is above 11 volts 2 Start with key switch OFF 3 Turn key switch to ON and OFF then ON and OFF then ON leaving it on in third sequence Do not start engine Time between sequences must be less than 2 5 seconds 4 MIL will blink a series of times Number of times MIL blinks represents a number in blink code 5 Asequence of four digits make up a fault code There is a one 1 second pause between blinks of a fault code There is a three 3 second pause between separate fault codes After fault code s are blinked a two digit 61 is blinked to indicate program has completed a It s a good idea to write down codes as they appear as they may not be in numerical sequence b Code 61 will always be last code displayed indicating end of code transmission If code 61 appears immediately no other fault codes are present After problem has been corrected fault codes may be cleared by following ECU Reset and TPS Learn Procedures Diagnostic Fault Code Summary lists fault codes and what they correspond to Diagnostic Code Summary is a list of individual codes with an explanation of what triggers them what symptoms might be expected and probable causes A MIL may not be provided with engine If equipment manufacturer has not added a MIL to equipment one can be added easily for quick diagnostics Main engine to
218. ying voltage signal to ECU in direct correlation to angle of throttle plate This signal along with other sensor signals is processed by ECU and compared to internal pre programmed maps to determine required fuel and ignition settings for amount of load Correct position of TPS is established and set at factory Do not loosen TPS or alter mounting position unless absolutely required by fault code diagnosis or throttle shaft service If TPS is loosened or repositioned appropriate TPS Initialization Procedure must be performed to reestablish baseline relationship between ECU and TPS Engine oil temperature sensor is used by system to help determine fuel requirements for starting a cold engine needs more fuel than one at or near operating temperature Mounted in oil filter adapter housing it has a temperature sensitive resistor that extends into oil flow Resistance changes with oil temperature altering voltage sent to ECU Using a table stored in its memory ECU correlates voltage drop to a specific temperature Using fuel delivery maps ECU then knows how much fuel is required for starting at that temperature 50 KohlerEngines com Oxygen sensor functions like a small battery generating a voltage signal to ECU based upon difference in oxygen content between exhaust gas and ambient air Tip of sensor protruding into exhaust gas is hollow Outer portion of tip is surrounded by exhaust gas with inner portion exposed

ECV630-ECV749, CV735, CV26, CV745 Service Manual

Contents

Download Pdf Manuals

Related Search

Related Contents