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CV940-CV1000 Service Manual

1. Cs AN ay by a As U li S ys al y N R VE SMB 5 E RI A Rd bo SY A Camshaft B Locking Tab C Regulating Pin D Governor Gear E Cross Shaft F Lifter Feed Cover Gasket G Lifter Feed Cover H Governor Yoke l Crankshaft J Connecting Rod End Cap K Connecting Rod L Piston Pin M Piston Pin Retainer N Piston o Piston Ring Set P Oil Seal Q Crankshaft Bearing Flywheel 56 KohlerEngines com NOTE Make sure engine is assembled using all specified torgue values torgue seguences 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 guickly break down lubricating properties of engine oil Check oil pan crankcase cylinder heads and valve covers to be certain all old gasket material has been removed Use gasket remover lacquer thinner or paint remover to remove any remaining traces Clean surfaces with isopropyl alcohol acetone lacguer thinner or electrical contact cleaner Install Flywheel End Oil Seal 1 Make sure seal bore of crankcase is clean and free of any nicks or burrs 2 Apply a light coat of clean engine oil to outside diameter of oi
2. Every 150 Hours e Check heavy duty air cleaner element Air Cleaner Intake e Replace fuel filter e Check oil cooler fins clean as necessary Lubrication System Every 300 Hours e Change oil filter Lubrication System e Replace heavy duty air cleaner element Air Cleaner Intake Every 500 Hours e Have crankshaft splines lubricated Every 600 Hours e Replace heavy duty inner air cleaner element Air Cleaner Intake e Replace spark plugs and set gap Electrical System 1 Perform these procedures more frequently under severe dusty dirty conditions 2 Have a Kohler authorized dealer perform this service 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 Canada 62 690 02 Rev D KohlerEngines com 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 j F 20 0 20 32 40 50 60 80 100 PC 30 20 10 0 10 20 30 40 FUEL RECOMMENDATIONS A WARNING Explosive Fuel can cause fires and severe i burns
3. 1 Install dipstick tube with a new lower O Ring into crankcase Secure with lower mounting screw Torque screw to 4 0 N m 35 in Ib 2 Attach lift bracket if used onto crankcase with screws Torque screws to 9 9 N m 88 in lb 3 Align and install blower housing Secure with screws Torque screws to 4 0 N m 35 in Ib into new holes or 2 0 N m 18 in Ib into used holes 4 Install cylinder shrouds and secure with screws Torque screws to 4 0 N m 35 in Ib into new holes or 2 0 N m 18 in Ib into used holes Install Muffler 1 Install new exhaust gaskets onto exhaust studs 2 Install port liners if equipped Attach muffler and secure with nuts onto exhaust studs Torque nuts to 24 4 N m 216 in lb 3 Install any attaching hardware and brackets Torque M6 screws to 9 9 N m 88 in Ib and M8 screws to 24 4 N m 216 in Ib 4 Install spark arrestor if used 68 KohlerEngines com Prepare Engine for Operation Engine is now completely reassembled Before starting or operating engine follow proceeding steps 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 Adjust carburetor idle fuel needles or idle speed adjusting screw as necessary Testing Engine It is recommended engine be operated on a test stand or bench prior to installation in equipment 1 Set engine up on a test
4. Conclusion Resistance is 0 1 0 2 ohms Stator is OK Resistance is 0 ohms Stator is shorted replace Resistance is infinity ohms 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 62 690 02 Rev D 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 KohlerEngines com 37 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 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 NOTE Do not d
5. B 1 5 2 0 mm cap into appropriate cylinder bore as previously 0 059 0 078 in marked at disassembly Do not mix end caps and connecting rods c Oil Seal D 12 56 mim ientati i i 0 498 in NOTE Proper orientation of piston connecting rod assemblies inside engine is extremely important E Crankcase Surface F Governor Gear Improper orientation can cause extensive wear Shaft or damage Be certain pistons and connecting If governor shafts seal and or governor gear were re rods are assembled exactly as shown moved reassemble as follows 1 Stagger piston rings in grooves until end gaps are 1 Lightly oil lip and outside diameter of new governor 120 apart Oil ring rails should also be staggered cross shaft seal Install seal into crankcase to depth 2 Lubricate cylinder bore piston and piston rings with shown engine oil Compress rings of piston side 1 using a 2 If governor gear shaft was removed press or lightly piston ring compressor tap replacement shaft into oil pan to depth shown 3 Lubricate crankshaft journals and connecting rod 3 Lubricate governor cross shaft bearing surfaces in bearing surfaces with engine oil crankcase with engine oil Insert governor cross 4 Make sure FLY stamping on piston is facing toward shaft end with flat cutout where governor yoke is flywheel side of engine Use a hammer with a rubber secured into crankcase and position shaft so that grip and gently tap piston into cylinder Be careful oil flat part
6. 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 Thread Size 14 mm Gap 0 76 mm 0 03 in Reach 19 1 mm 3 4 in Hex Size 15 9 mm 5 8 in Refer to maintenance for Repairs Service Parts Service 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 30 KohlerEngines com 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 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 by excess fuel or oil in combustion chamber Excess fuel could be caused by a restricted air cleaner a carbureto
7. KOHLER Command PRO CV940 CV1000 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 13 Tools and Aids 16 Troubleshooting 20 Air Cleaner Intake 21 Fuel System 27 Governor System 28 Lubrication System 30 Electrical System 38 Starter System 42 Disassembly Inspection and Service 56 Reassembly 62 690 02 Rev D 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 GLU 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 WARNING Accidental Starts can cause severe injury or death
8. 95 in Ib for new holes or 7 3 Nm 65 in Ib for used holes Install Oil Cooler 1 Connect hoses between oil filter adapter and oil cooler Secure with new clamps KohlerEngines com 65 Reassembly 2 Align oil cooler with bosses in backing shroud assembly Secure screws and washers to 2 2 N m 20 in Ib Install Cooling Fan and Debris Screen A CAUTION Failure to utilize or reassemble debris screen as designed could result in debris screen Ro failure and serious personal injury CF 1 Position cooling fan onto flywheel aligning mounting locations Apply a small amount of Loctite 243 Threadlocker to threads and install long mounting screws Torque screws to 9 9 N m 88 in lb 2 Apply a small amount of Loctite 243 Threadlocker to external threaded section unless new parts with preapplied locking compound are being used Thread debris screen hex studs into mounting holes in flywheel Torque each stud to 9 9 N m 88 in Ib Control Bracket Components Install stiffener followed by metal debris screen onto studs Secure with special washers and mounting screws using Loctite 243 Threadlocker on threads Torque screws to 9 9 N m 88 in Ib Install Electric Starter 1 2 Torque screws to 15 3 N m 135 in Ib 3 Connect leads to solenoid Install electric starter motor using screws Install Valley Baffles 1 Install valley baffles and secure w
9. ii EXH Dimension Intake Exhaust A Seat Angle 89 89 B Seat Taper 30 30 C Guide Depth 8 5 mm 0 334 in 8 5 mm 0 334 in D Guide D 7 038 7 058 mm 0 2771 0 2779 in 7 038 7 058 mm 0 2771 0 2779 in E Valve Head Diameter 38 625 38 685 mm 1 5206 1 5230 in 31 625 31 825 mm 1 2450 1 2549 in F Valve Face Angle 45 45 G Valve Margin Min 1 0 mm 0 0393 in 1 0 mm 0 0393 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 62 690 02 Rev D KohlerEngines com 47 Disassembly Inspection and Service After cleaning check flatness of cylinder head and corresponding top surface of crankcase using a surface plate or piece of glass and feeler gauge Maximum allowable out of flatness is 0 076 mm 0 003 in 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 Hard starting or loss of power accompanied by high fuel consumption may be symptoms of faulty valves Although these symptoms could also be attributed to worn rings remove and check valves first After removal 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
10. 0 0015 0 0065 in Oil Pan End Main Bearing Journal New O D Max Wear Limit Max Taper Max Out of Round 44 978 45 00 mm 1 770 1 771 in 44 90 mm 1 767 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 Max Out of Round Width 43 982 44 000 mm 1 731 1 732 in 43 97 mm 1 731 in 0 018 mm 0 0007 in 0 025 mm 0 0010 in 53 00 53 09 mm 2 0866 2 0901 in T LR PTO End Crank in Engine Entire Crank in V Blocks 0 279 mm 0 0110 in 0 10 mm 0 0039 in Flywheel End Main Bearing Journal O D New O D Max Wear Limit Max Taper Max Out of Round 44 978 45 00 mm 1 770 1 771 in 44 90 mm 1 767 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in Crankshaft Bearing flywheel PTO New installed Max Wear Limit 45 040 45 145 mm 1 773 1 777 in 45 158 mm 3Values are in Metric units Values in parentheses are English equivalents 62 690 02 Rev D KohlerEngines com Specifications CLEARANCE SPECIFICATIONS CV940 CV960 CV980 CV1000 Cylinder Bore Max Out of Round I D New 90 000 90 025 mm 3 543 3 544 in Max Wear Limit 90 075 mm 3 546 in Max Taper 0 013 mm 0 00051 in 0 013 mm 0 00051 in Cylinder Head Max Out of Flatness 0 076 mm 0 003 in Governor Governor Cross Shaft to Crankcase Running Clearance 0 025 0 087 mm 0
11. Disconnect negative battery cable 4 Store engine in a clean dry place 62 690 02 Rev D Specifications Engine Dimensions Dimensions in millimeters Inch equivalents shown in 130 00 5 118 62 70 2 468 Optional Guard j 470 64 DE Lae 18 529 SKM Kr M Ma Sal k g 411 64 16 206 376 56 14 825 Arne Ae ix 1 378 275 10 25 0 0 98 DEEP 7 HOLES 89 80 3 536 62 690 02 Rev D KohlerEngines com 5 Specifications ENGINE IDENTIFICATION NUMBERS Kohler engine identification numbers model specification and serial should be referenced for efficient repair ordering correct parts and engine replacement Model 4 eee snes CV940 Command Engine Vertical Shaft Numerical Designation Specification CV940 0001 SOMA u de her ae 2248414404 3923500328 Year Manufactured Code Factory Code Code Year 39 2009 40 2010 41 2011 GENERAL SPECIFICATIONS CV940 CV960 CV980 CV1000 Bore 90 mm 3 54 in Stroke 78 5 mm 3 1 in Displacement 999 cc 61 cu in Oil Capacity refill 2 9 L 3 1 U S qt Maximum Angle of Operation full oil level 25 TORQUE SPECIFICATIONS CV940 CV960 CV980 CV1000 Blower Housing and Sheet Metal M6 Screw New Untapped Hole casting 10 7 Nm 95 in Ib Used Ta
12. Main Jet y Main Jet Inlet Needle Right Side Left Side Right Side Left Side Z Choke Dust Cap AA Choke Shaft AB Spring AC Bushing AD Choke Lever Choke Plate AE Choke Plate AF Screw 22 KohlerEngines com 62 690 02 Rev D Engines in this series are equipped with a two barrel side draft carburetor with fixed main jets on a matching intake manifold Carburetor features a self relieving choke serviceable slow jets main jets bowl drain and a fuel shutdown solenoid Troubleshooting Checklist When engine starts hard runs rough or stalls at low idle speed check these areas before adjusting or disassembling carburetor 1 Make sure fuel tank is filled with clean fresh gasoline 2 Make sure fuel tank cap vent is not blocked and is Fuel System Make sure fuel is reaching carburetor This includes checking fuel shut off valve fuel tank filter screen in line fuel filter fuel lines and fuel pump for restrictions or faulty components as necessary Make sure air cleaner base and carburetor are securely fastened to engine using gaskets in good condition Make sure air cleaner element including precleaner if equipped is clean and all air cleaner components are fastened securely Make sure ignition system governor system exhaust system and throttle and choke controls are operating properly operating properly Troubleshooting Carburetor Related Causes Condition Possible Cause Conclusion Eng
13. N Breather Assembly o Breather Gasket P Filter Q Breather Hose R Oil Seal Remove Breather Assembly 1 Remove fasteners securing breather assembly and gasket to crankcase 2 Carefully break gasket seal and remove breather and filter Do not pry on sealing surfaces as it could cause damage resulting in leaks Note assembly and orientation of parts 62 690 02 Rev D Remove Oil Pan Assembly 1 Remove screws securing oil pan to crankcase 2 Locate protruding tabs on oil pan Carefully tap to break gasket seal Do not pry on sealing surfaces as this could cause leaks Separate oil pan from crankcase Remove old gasket Inspection Inspect oil seal in oil pan and remove it if it is worn or damaged Inspect crankshaft bearing surface for wear or damage Replace bearing or oil pan assembly if required KohlerEngines com 49 Disassembly Inspection and Service Oil Pump Assembly Dis 1 assembly Remove screws securing oil pump housing including relief valve baffle and screw for pickup tube 2 Remove oil pump housing and pickup tube from oil pan 3 Remove oil pump gerotor gears from oil pan recess 4 Remove oil pickup by pulling it free from oil pump body 5 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 ger
14. Pressure Test Kit Kohler 25 761 06 S Rectifier Regulator Tester 120 V AC 60Hz Kohler 25 761 20 S 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 Tools KLR 82407 For holding flywheel of CS series engines Fiywheel Puller SE Tools KLR 82408 For properly removing flywheel from engine Flywheel Strap Wrench SE Tools KLR 82409 For holding flywheel during removal 62 690 02 Rev D KohlerEngines com 13 Tools and Aids TOOLS Description Source Part No Hydraulic Valve Lifter Tool For removing and installing hydraulic
15. To aid assembly install lower oil cooler hose onto oil filter housing prior to installing backing shroud assembly and secure with a clamp 2 Install backing shroud assembly and secure to crankcase with M6 screws Torque screws in a crisscross pattern to 10 7 N m 95 in Ib into new holes or 7 3 N m 65 in Ib into used holes Install Stator Wiring Harness and Rectifier Regulator 1 Apply pipe sealant with Teflon Loctite PST 592 Thread Sealant or equivalent to stator mounting holes 2 Position stator aligning mounting holes so leads are at bottom and toward rectifier regulator mount on cylinder 1 side 3 Install and torque screws to 6 2 N m 55 in Ib 4 Route stator wires under molded clips in backing shroud assembly 5 Check terminal on end of B charging lead to be sure locking tang is angled upward Insert terminal into center location of connector until it locks into place 6 Install wiring harness under molded clips in backing shroud assembly 7 Position rectifier regulator onto mounting posts with cooling fins up Attach ground lead to outer screw and washer then torque mounting screws to 2 0 N m 18 in Ib Connect plug to rectifier regulator Install Flywheel A CAUTION Damaging Crankshaft and Flywheel can cause personal injury I Using improper procedures can lead to broken fragments Broken fragments could be thrown from engine Always observe and use precautio
16. amp 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 overfill fuel tank e Do not use gasoline older than 30 days 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
17. 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 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 hold
18. 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 3 Invert segment and place it between ignition bosses gung 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 62 690 02 Rev D KohlerEngines com 15 Troubleshooting TROUBLESHOOTING GUIDE When troubles occur be sure to check simple causes 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 Carb
19. 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 Disconnect Spark Plug Leads NOTE Pull on boot only to prevent damage to spark plug lead 1 Disconnect leads from spark plugs 2 Shut off fuel supply Drain Oil from Crankcase and Remove Oil Filter 1 Clean oil filter and housing area Remove and discard oil filter 2 Remove dipstick and 1 oil drain plug 3 Allow ample time for oil to drain from crankcase Remove Muffler Remove exhaust system and attaching hardware from engine Remove Cylinder Shrouds and Blower Housing 1 Remove top mounting screw and loosen shoulder screws on each side Lift off cylinder shrouds 2 Remove mounting screws and separate blower housing from backing shroud assembly One screw also secures oil fill dipstick tube Fixed guard if equipped may be removed with blower housing 3 Remove lower mounting screw and pull oil fill tube out of crankcase Remove Electric Starter Motor 1 Disconnect leads from starter 2 Remove screws and starter Remove Air Cleaner Assembly 1 Disconnect breather hose f
20. 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 connections that intermittently ground ignition kill circuit e Low compression e Quality of fuel dirt water stale mixture e Weak spark 16 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 Radia
21. is visible up ring rails do not spring free between bottom of ring 4 Attach governor yoke to cross shaft so curved compressor and top of cylinder section is up as marked Secure with screws If a 5 Install inner rod cap to connecting rod using screws thread locking compound is not preapplied apply a Torque screws in increments to 11 3 N m 100 in small amount of Loctite 266 Threadlocker or Ib Illustrated instructions are provided in service equivalent to screw threads before installing Torque rod package screws to 2 2 N m 20 in lb Align chamfer of connecting rod with chamfer of its 5 Install first regulating pin with head down so it will mating end cap When installed flat faces of contact yoke Install governor gear with second connecting rods should face each other Faces with regulating pin and flyweight assembly in down onto raised rib should be toward outside governor shaft until it locks into position Apply a A small amount of grease to locking tab thrust washer 6 Repeat this procedure for other connecting rod and and install on top of governor gear so tang is facing piston assembly up in 6 o clock position 62 690 02 Rev D KohlerEngines com 57 Reassembly Breather Oil Pan Components Breather Fastener Torque Sequence 3 Gerotor Gears Install Camshaft 1 58 Liberally apply camshaft lubricant to each cam lobe Lubricate camshaft
22. 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 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
23. 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 Conclusion Solenoid fails to activate No continuity is indicated Plunger fails to stay retracted Replace solenoid 62 690 02 Rev D KohlerEngines com 41 Disassembly Inspection and Service A WARNING death before servicing Accidental Starts can cause severe injury or Disconnect and ground spark plug lead s 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 A Oil Filter B Oil Filter Nipple C Oil Filter Cup D Valve Spring E Cup Spring F Valve G Oil Filter Housing H Valley Baffle I Outer Cylinder Baffle J Electric Starter K Cylinder Shroud L Blower Housing M Fixed Guard N Oil Sentry o O Ring P Pin Q Fitting R Oil Cooler S Hose T Hose Clamp U Gasket V Carburetor WwW Intake Manifold 42 KohlerEngines com 62 690 02 Rev D Clean all parts thoroughly as engine is disassembled Only clean parts can be accurately inspected and gauged for wear or
24. 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 17 Troubleshooting CRANKCASE VACUUM TEST A WARNING Carbon Monoxide can cause severe nausea fainting or death Avoid inhaling exhaust fumes A 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
25. proper operation and free movement of parts Install new cap 18 Clean carburetor body main jets vent ports seats etc using a good commercially available carburetor solvent Keep away from plastic or rubber parts if non compatible Use clean dry compressed air to blow out internal channels and ports Do not use metal tools or wire to clean orifices and jets Inspect and thoroughly check carburetor for cracks wear or damage Inspect fuel inlet seat for wear or damage Check spring loaded choke plate to make sure it moves freely on shaft 19 Install main nozzles into towers of carburetor body End of main nozzles with 2 raised shoulders should be out down adjacent to main jets Make sure nozzles are completely bottomed Carefully install main jets into towers of carburetor body on appropriate side as identified when removal was performed 20 Make sure O ring near bottom of each slow jet is new or in good condition Align and insert slow jets into top of carburetor 21 Install large flat retaining washer and secure with mounting screw attaching ground lead if originally secured by screw 22 Install new idle speed RPM adjustment screw and spring onto carburetor Thread in until 3 or 4 threads are exposed as an initial adjustment 23 Attach inlet needle to plastic tang of float with wire clip Formed 90 lip should point up with needle valve hanging down 24 Install float and inlet needle down into seat and c
26. torque in 2 increments Head Bolt first to 22 6 N m 200 in Ib finally to 45 2 N m 400 in Ib Pipe Plug 3 4 in 28 25 N m 250 in Ib Rocker Arm Stud AVT 11 3 N m 100 in Ib Setscrew AVT pivot locking 7 3 Nm 65 in Ib Debris Screen Hex Stud 9 9 N m 88 in Ib Mounting Screw 9 9 N m 88 in Ib Flywheel Fan Fastener 9 9 N m 88 in Ib Retaining Screw 67 8 N m 50 ft Ib Fuel Pump Screw 8 0 12 1 N m 71 107 in Ib into new holes 6 0 9 0 N m 53 80 in Ib into used holes Governor Lever Nut 7 3 N m 65 in Ib Yoke Mounting Screw 2 2 N m 20 in Ib Ignition Spark Plug 27 N m 20 ft Ib Module Fastener 6 2 N m 55 in Ib into new holes 4 0 N m 35 in Ib into used holes Rectifier Regulator Fastener 2 0 N m 18 in Ib Lifter Feed Chamber Cover Screw 6 2 N m 55 in Ib into new holes 4 0 N m 35 in Ib into used holes Muffler Retaining Nut 24 4 N m 216 in Ib Screw intermittent bracket into weld nut 13 5 N m 120 in Ib Oil Cooler Mounting Screw 2 2 N m 20 in Ib Oil Filter Adapter Housing Mounting Screw 24 4 N m 216 in Ib Oil Filter Nipple 18 N m 159 in Ib Oil Pan Fastener 27 N m 238 in Ib Oil Pickup Tube Mounting Screw 10 7 N m 95 in Ib into a new hole 7 3N m 65 in Ib into a used hole 3Values are in Metri
27. work Main high speed At high speeds loads engine operates on main circuit As a metered amount of air is drawn through 4 air jets fuel is drawn through main jets Air and fuel are mixed in main nozzles then enter main body of airflow where further mixing of fuel and air occurs This mixture is then delivered to combustion chamber Carburetor has a fixed main circuit no adjustment is possible 24 KohlerEngines com NOTE Carburetor adjustments should be made only after engine has warmed up Carburetor is designed to deliver correct fuel to air mixture to engine under all operating conditions Main fuel jet is calibrated at factory and is not adjustable Idle fuel adjusting needles are also set at factory and normally do not need adjustment Low Idle Speed RPM Adjustment NOTE Actual low idle speed depends on application Refer to equipment manufacturer s recommendations Low idle speed for basic engines is 1200 RPM To ensure best results when setting low idle fuel needle low idle speed should be 1200 RPM 75 RPM Place throttle control into idle or slow position Turn low idle speed adjusting screw in or out to obtain a low idle speed of 1200 RPM 75 RPM N Idle Speed Adjustment Make sure governed idle spring is in outer hole in governor lever and hole in governed idle outer adjuster 2 Make sure governor spring is in inner slot of governor lever and hole in high speed inner adjuster Pull governor le
28. 0009 0 0034 in Cross Shaft O D New Max Wear Limit 7 963 8 000 mm 0 3135 3149 in 7 936 mm 0 3124 in Governor Gear Shaft to Governor Gear Running Clearance 0 070 0 160 mm 0 0027 0 0063 in Gear Shaft O D New Max Wear Limit 5 990 6 000 mm 0 2358 0 2362 in 5 977 mm 0 2353 in Ignition Spark Plug Gap 0 76 mm 0 030 in Module Air Gap 0 28 0 33 mm 0 011 0 013 in Piston Piston Rings and Piston Pin Piston to Piston Pin Running Clearance 0 006 0 018 mm 0 0002 0 0007 in Max Wear Limit Top Compression Ring to Groove Side Clearance Pin Bore I D New 19 006 17 013 mm 0 7482 0 7485 in Max Wear Limit 19 025 mm 0 7490 in Pin O D New 18 995 19 000 mm 0 7478 0 7480 in 18 994 mm 0 7478 in 0 04 0 08 mm 0 0015 0 0031 in Middle Compression Ring to Groove Side Clearance 0 04 0 08 mm 0 0015 0 0031 in Oil Control Ring to Groove Side Clearance Top and Center Compression Ring End Gap New Bore Used Bore max 0 03 0 19 mm 0 0011 0 0074 in 0 30 0 55 mm 0 011 0 021 in 0 94 mm 0 037 in Thrust Face O D New Max Wear Limit 89 953 89 967 mm 3 5414 3 5420 in 89 925 mm 3 540 in Piston Thrust Face to Cylinder Bore Running Clearance New 0 033 0 071 mm 0 0013 0 0028 in 3Values are in Metric units Values in parentheses are English equivalents 7 Measure 11 mm 0 433 in above bottom of piston s
29. 2 690 02 Rev D 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 800 664 298 1 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 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 S For checking combustion retention 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
30. 8 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 3 8 16 47 5 35 54 2 40 81 4 60 47 5 35 74 6 55 108 5 80 61 0 45 101 7 75 142 5 105 67 8 50 108 5 80 155 9 115 94 9 70 142 4 105 223 7 165 101 7 75 169 5 125 237 3 175 135 6 100 223 7 165 311 9 230 149 5 110 244 1 180 352 6 260 189 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 Torgue Recommendations for Standard Applications Property Class Noncritical Size mio 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 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 N m ft Ib x 1 356 in lb N m x 8 85 ft Ib N m x 0 737 12 KohlerEngines com 6
31. Disconnect and ground spark plug lead s before gt servicing Pe A CAUTION X Electrical Shock can cause injury w 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 A WARNING ry Rotating Parts can cause severe injury Stay away while engine is in operation A WARNING A CAUTION Damaging Crankshaft and Flywheel can cause Ro personal injury IR Hot Parts can cause severe burns li Do not touch engine while operating or just after stopping 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 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 A 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 A WARNING Cleaning Solvents can 4 cause severe injury or death Use only in well ventila
32. Do not replace bearings unless they show signs of damage or are out of running clearance 0 040 0 167 mm 0 0015 0 0065 in If crankshaft turns easily without noise 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 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 Clearance Specifications are exceeded it will be necessary to 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 Clearance Specifications Connecting Rod Journal O D New 43 982 44 000 mm 1 731 1 732 in 43 97 mm 1 731 in O D Max Wear Limit Max Taper 0 018 mm 0 0007 in Max Out of Round 0 025 mm 0 0010 in Width 53 00 53 09 mm 2 0866 2 0901 in Connecting rod journal can be ground 1 size under When grinding a crankshaft grinding stone deposits can get caught in oil passages which could cause severe engine damage Removing crankpin plug when crankshaft is ground provides easy access for removing any grinding deposits that may collect in oil passages Use following pro
33. Inspect governor weights They should move freely in governor gear Remove Governor Yoke Cross Shaft and Seal 1 Remove mounting screws securing yoke to governor cross shaft 2 Pull governor cross shaft out of crankcase and remove seal Remove Lifter Feed Chamber Cover and Gaskets Remove screws securing lifter feed chamber cover and gaskets Carefully separate parts from crankcase Remove Flywheel and PTO End Oil Seals Remove oil seals from crankcase and oil pan using a seal puller Remove Crankshaft Bearings flywheel PTO NOTE Bearing should only be removed if replacement is required due to wear If removal is performed use a press and support casting surface around bearing flange Do not press against or support by gasket outer perimeter surface 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 crankshaft bearing if equipped for wear or damage Replace bearing or crankcase using a miniblock or short block as required Check cylinder bore 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 resulting from bloc
34. Note orientation of pump before removing 1 Disconnect fuel lines from inlet outlet and pulse fittings on fuel pump 2 Remove screws and take off pump 3 Connect pulse line to new fuel pump and make sure opposite end is properly connected to oil filter housing fitting 4 Attach new fuel pump using screws Torque screws to 8 0 12 1 N m 71 107 in Ib into new holes or 6 0 9 0 N m 53 80 in Ib into used holes 5 Reconnect fuel lines to inlet and outlet fittings and secure with clamps When engine starts hard or turns over but will not start fuel system might be causing problems Test fuel system by performing following test 1 Check for fuel in combustion chamber a Disconnect and ground spark plug leads b Close choke on carburetor c Crank engine several times d Remove spark plug and check for fuel at tip 2 Check for fuel flow from tank to fuel pump a Remove fuel line from inlet fitting of fuel pump b Hold line below bottom of tank Open shut off valve if equipped and observe flow Condition 3 Check operation of fuel pump a Remove fuel line from inlet fitting of carburetor b Crank engine several times and observe flow Conclusion Fuel at tip of spark plug Fuel is reaching combustion chamber No fuel at tip of spark plug Check fuel flow from fuel tank step 2 Fuel flows from fuel line Check for faulty fuel pump step 3 If fuel pump is working check for
35. Turn power source ON and observe pin in center of solenoid Pin should retract with power ON and return to its original position with power OFF Test several times to verify operation Carburetor Circuits Float Fuel level in bowl is maintained by float and fuel inlet needle Buoyant force of float stops fuel flow when engine is at rest When fuel is being consumed float will drop and fuel pressure will push inlet needle away from seat allowing more fuel to enter bowl When demand ceases buoyant force of float will again overcome fuel pressure rising to predetermined setting and stop flow Slow and Mid Range At low speeds engine operates only on slow circuit As a metered amount of air is drawn through slow air bleed jets fuel is drawn through 2 main jets and further metered through slow jets Air and fuel are mixed in body of slow jet and exit to transfer port From transfer port air fuel mixture is delivered to idle progression chamber From idle progression chamber air fuel mixture is metered through idle port passages At low idle when vacuum signal is weak air fuel mixture is controlled by setting of idle fuel adjusting screws This mixture is then mixed with main body of air and delivered to engine As throttle plate opening increases greater amounts of air fuel mixture are drawn in through fixed and metered idle progression holes As throttle plate opens further vacuum signal becomes great enough so main circuit begins to
36. aft and into mesh with flywheel ring gear When pinion reaches end of drive shaft it rotates flywheel and cranks engine When engine starts and start switch is released starter solenoid is deactivated drive lever moves back and drive pinion moves out of mesh with ring gear into retracted position Solenoid Shift Starter Components 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 a Brush Holder R Nut s Commutator End T Screw Plate U Bolt 62 690 02 Rev D Starter System 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 hex nut and disconnect positive brush lead bracket from solenoid terminal 2 Remove head screws securing solenoid to starter 3 Unhook plunger pin from drive lever Remove gasket from recess in housing 4 Remove thru larger bolts 5 Remove commutator end plate assembly containing brush holder brushes springs and locking caps Remove thrust washer from inside commutator end 6 Remove frame from armature and drive end cap 7 Remove drive lever pivot bushing and backing plate if eguipped from end cap 8 Take out drive lever and pull armature out of drive end cap 9 Remove
37. ainers e Valve springs e Valve spring keepers e Valve stem seals e Guide plate e Pivot studs Install Cylinder Heads Torque Sequence 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 2 Check dowel pins are in place in 2 lower locations and install a new cylinder head gasket printed side up 3 Install cylinder head Make sure head is flat on gasket and dowel pins Install a flat washer on screws in locations 1 and 3 Install spacer followed by a flat washer on screw in location 5 Start 5 screws 4 Torque screws in 2 stages first to 22 6 Nm 200 in Ib finally to 45 2 N m 400 in Ib following sequence shown 5 Repeat procedure for opposite cylinder 6 Make sure threads of pipe plugs for cylinder heads are clean and dry Install a plug into each cylinder head above screw on location 2 and torque to 28 25 Nm 250 in lb 62 690 02 Rev D Reassembly Install Guide Plate Pivot Studs Push Rods and Rocker Arms NOTE Install push rod guide plate so flange is down towards cylinder on side 1 and up away from cylinder on side 2 NOTE Push rods should always be installed in same position as before in disassembly 1 Install push rod guide plate and rocker arm pivot studs onto cylinder heads if removed previously Torque studs to 11 3 N m 100 in Ib 2 No
38. al contact cleaner to remove any old dielectric compound dark residue dirt or contamination Disconnect spark plug leads from spark plugs 3 Using a multi meter check that a proper ground is established between ground black lead of DSAI module closest to spark plug lead and a known good ground location on engine 4 Turn key switch to ON position and check for 12 volts at center power red lead terminal of DSAI module Use same ground location for multi meter as in checking for timing advance Condition Possible Cause Conclusion All tests are OK but module has no Ignition Module Replace affected module spark or fails to advance Any test is BAD Ignition Module or Connections Determine cause and fix as required retest 62 690 02 Rev D KohlerEngines com 35 Electrical System BATTERY CHARGING SYSTEM NOTE Observe following guidelines to avoid damage to 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 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 NOTE 20 amp charging systems use a 15 amp stator with a 25 amp rectifier regulator Most engines are equipped with a 15 20 or 25 amp regula
39. all passages blow out with compressed air Fuel leaks from carburetor Float level set too high Adjust float according to Float Replacement Procedure Dirt under fuel inlet needle Remove needle clean needle and seat and blow with compressed air Bowl vents plugged Blow out with compressed air Carburetor bowl gasket leaks Replace gasket 62 690 02 Rev D KohlerEngines com 23 Fuel System Fuel Shut off Solenoid Carburetor Adjustments Most carburetors are equipped with a fuel shut off solenoid Solenoid is attached to fuel bowl Solenoid has a spring loaded pin that retracts when 12 volts is applied to lead allowing fuel flow to main jets When current is removed pin extends blocking fuel flow Below is a simple test performed with engine off that can determine if solenoid is functioning properly 1 Shut off fuel and remove solenoid from carburetor When solenoid is loosened and removed gas will leak out of carburetor Have a container ready to catch fuel 2 Wipe tip of solenoid with a shop towel or blow with compressed air to remove any remaining fuel Take solenoid to a location with good ventilation and no fuel vapors present You will also need a 12 volt power source that can be switched on and off 3 Be sure power source is switched OFF Connect positive power source lead to red lead of solenoid Connect negative power source lead to solenoid body 4
40. arburetor body Install new pivot pin through float hinge and secure with new retaining screw 25 Hold carburetor body so float assembly hangs vertically and rests lightly against fuel inlet needle Inlet needle should be fully seated but center pin of needle on retainer clip end should not be depressed Check float height adjustment Be sure to measure from casting surface not rubber gasket if still attached 26 KohlerEngines com 26 Correct float height setting is 17 mm 0 669 in 1 5 mm 0 059 in measured from float bottom to body of carburetor Replace float if height is different than specified DO NOT attempt to adjust by bending float tab 27 When proper float height is obtained carefully reinstall fuel bowl onto carburetor using new O rings Secure with original screws Torque screws to 2 5 N m 22 in Ib 0 3 N m 3 in Ib 28 Set idle mixture screws at midpoint of available adjustment as a preliminary setting 29 Use new mounting gaskets for air cleaner and carburetor Reinstall carburetor and disassembled components following Reassembly procedures 30 Reconnect spark plug leads and negative battery cable Start engine and perform Low Idle Speed Adjustment and Low Idle Fuel Needle s settings HIGH ALTITUDE OPERATION This engine may require a high altitude carburetor kit to ensure correct engine operation at altitudes above 1219 meters 4000 ft To obtain high altitude kit information or to f
41. be size side specific After main jets are removed main nozzles can be removed out through bottom of main towers Note orientation direction of nozzles End with 2 raised shoulders should be out down adjacent to main jets Save parts for cleaning and reuse Remove screw securing flat washer and ground lead if equipped from top of carburetor then carefully pull lift out slow jets Slow jets may be sized side specific Mark or tag jets for proper reassembly Note small O ring on bottom of each jet Save parts for cleaning and reuse unless a jet kit is also being installed Clean slow jets using compressed air Do not use wire or carburetor cleaner Remove idle speed RPM adjustment screw and spring from carburetor Discard parts Carburetor is now disassembled for appropriate cleaning and installation of parts in overhaul kit Further disassembly is not necessary Throttle shaft assembly fuel inlet seat idle fuel adjustment screws with limiter and carburetor body are non serviceable items and should not be removed Choke shaft assembly is serviceable however it should not be removed unless a choke repair kit will be installed To install choke repair kit go to step 8 otherwise go to step 18 Remove and discard plastic cap from end of choke lever shaft assembly Note position of spring legs and choke plate for correct reassembly later Remove screws attaching choke plate to choke shaft Pull shaft out of carburetor body n
42. bearing surfaces of crankcase and camshaft with engine oil Position timing mark of crankshaft gear at 12 o clock position 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 KohlerEngines com A Oil Pan B C Oil Pump O Ring D Oil Pump Housing E Relief Valve Baffle F Pickup Tube G Inlet Seal H Pickup Screen l Drain Plug J cra TO K Oil Pan Gasket L Dipstick M Dipstick Tube N Breather Assembly o Breather Gasket P Filter Q Breather Hose R Oil Seal Determining Camshaft End Play 1 Place a new oil pan gasket into position on crankcase Position camshaft end play checking tool over camshaft Use a feeler gauge to check end play between camshaft and end play checking tool Camshaft endplay should be between 0 3 1 3 mm 0 011 0 051 in No shim is typically used from factory However if camshaft end play is not within specified range remove checking tool and shim as necessary 62 690 02 Rev D Several color coded shims are available White 0 69215 0 73025 mm 0 02725 0 02875 in Blue 0 74295 0 78105 mm 0 02925 0 03075 in Red 0 79375 0 83185 mm 0 03125 0 03275 in Yellow 0 84455 0 88265 mm 0 03325 0 03475 in Green 0 89535 0 99345 mm 0 03525 0 03675 in 0 94615 0 98425 mm 0 03725 0 03875 in 0 99695 1 03505 mm 0 03925 0 04075 in Gray Black 4 Re
43. c units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 62 690 02 Rev D KohlerEngines com 7 Specifications TORQUE SPECIFICATIONS CV940 CV960 CV980 CV1000 Oil Pump Mounting Screw 10 7 Nm 95 in Ib into new holes 6 7 N m 60 in Ib into used holes Oil Sentry Pressure Switch 10 1 N m 90 in lb Solenoid starter Mounting Hardware 4 0 6 0 N m 35 53 in Ib Nut Positive Brush Lead 8 0 11 0 N m 71 97 in Ib Starter Assembly Thru Bolt 5 6 9 0 N m 49 79 in lb Mounting Screw Brush Holder Mounting Screw Stator 15 3 Nm 135 in lb 2 5 3 3 N m 22 29 in lb Mounting Screw 6 2 N m 55 in Ib Throttle Choke Control Bracket Fastener 9 9 N m 88 in Ib Valve Cover Fastener 13 6 N m 120 in Ib CLEARANCE SPECIFICATIONS CV940 CV960 CV980 CV1000 Camshaft End Play 0 3 1 3 mm 0 011 0 051 in Running Clearance 0 025 0 063 mm 0 0010 0 0025 in Bore I D New 20 000 20 025 mm 0 7874 0 7884 in Max Wear Limit 20 038 mm 0 7889 in Bearing Surface O D New Max Wear Limit Cam Lobe Profile minimum dimension measured from base circle to top of lobe Exhaust 19 962 19 975 mm 0 7859 0 7864 in 19 959 mm 0 7858 in 35 mm 1 3779 in Intake 1 3425 in 34 1 mm 35 mm 1 3779 in 3Values are in Met
44. case CV940 CV1000 Governor Idle Spring Color High Speed RPM Clear 1400 1625 RPM Black 1626 1800 RPM CV940 CV960 CV980 Governor Spring Color High Speed RPM NOTE Make sure both oil drain plugs are installed and torqued to 21 4 N m 16 ft Ib to prevent oil leakage 1 Install oil drain plugs Torque plugs to 21 4 N m 16 ft Ib 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 new Orange 3000 3100 RPM filter Red 3101 3300 RPM 4 Refer to instructions on oil filter for proper installation 3301 3750 RPM Se 5 Fill crankcase with new oil Level should be at top of Purple 3751 3900 RPM indicator on dipstick CV1000 6 Reinstall oil fill cap dipstick and tighten securely Governor Spring Color High Speed RPM Connect Spark Plug Leads Orange 3000 3100 RPM Connect leads to spark plugs Red 3101 3300 RPM Purple 3301 3900 RPM Install Oil Sentry if equipped 1 Apply pipe sealant with Teflon Loctite PST 592 Thread Sealant or equivalent to Oil Sentry threads switch and install it into 1 8 in port in oil pan Torque switch to 10 1 N m 90 in Ib 2 Connect green wire lead to Oil Sentry terminal Install Blower Housing and Cylinder Shrouds
45. ced 62 690 02 Rev D KohlerEngines com 19 Air Cleaner Intake AIR CLEANER These systems are CARB EPA certified and components should not be altered or modified in any way Air Cleaner Components A Air Cleaner Housing B End Cap C Element D Inner Element E Ejector Area F Inlet Screen G Retaining Clip H Filter Minder 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 20 KohlerEngines com 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 both ends of breather tube are properly connected AIR COOLING A WARNING zt Hot Parts can cause severe burns Gullit Gi wit 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 wa
46. cedure to remove and replace plug 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 Install New Crankshaft Plug Use 1 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 KohlerEngines com 53 Disassembly Inspection and Service Remove Governor Gear Assembly 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 If governor cross shaft yoke or gear condition does not require removal governor gear may be left in place If removal is necessary perform as follows 1 Remove locking tab thrust washer and note orientation 2 Using a screwdriver carefully pry upward to unseat governor gear assembly from governor gear shaft Remove regulating pin and governor gear assembly 3 Inspect governor gear shaft for wear or damage Remove shaft only if replacement is needed Inspection Governor gear is located within crankcase Inspect governor gear teeth Replace gear if it is worn chipped or if any teeth are missing
47. cross shaft protrudes through crankcase Rotating action of cross shaft is transmitted to throttle lever of carburetor through external throttle linkage When engine is at rest and throttle is in fast position tension of governor spring holds throttle plate open When engine is operating governor gear assembly is rotating Force applied by regulating pin against cross shaft tends to close throttle plate Governor spring tension and force applied by regulating pin balance each other during operation to maintain engine speed When load is applied and engine speed and governor gear speed decreases governor spring tension moves governor arm to open throttle plate wider This allows more fuel into engine increasing engine speed As speed reaches governed setting governor spring tension and force applied by regulating pin will again offset each other to hold a steady engine speed 62 690 01 Rev C KohlerEngines com NOTE Do not tamper with governor setting Overspeed is hazardous and could cause personal injury Initial Adjustment Procedure Make this adjustment whenever governor arm is loosened or removed from cross shaft Adjust as follows 1 Make sure throttle linkage is connected to governor arm and throttle lever on carburetor Loosen nut holding governor lever to cross shaft Move governor lever toward carburetor as far as it will go wide open throttle and hold in this position 4 Inserta long thin rod or tool into h
48. cup 62 690 02 Rev D Flywheel Ignition Components Disassembly Inspection and Service Remove Ignition Modules 62 690 02 Rev D A Special Washer B Debris Screen C Stiffener D Hex Stud E Fan F Flywheel Screw G Washer H Ignition Module I Wire Harness Clamp J Flywheel K Magnet L Stator M Rectifier Regulator N Backing Shroud o Woodruff Key 1 Rotate flywheel so magnet is away from modules 2 Remove mounting screws and disconnect kill lead from ignition modules Note position of ignition modules and wiring harness clip Remove Debris Screen and Cooling Fan Remove screws attaching hardware and hex studs securing debris screen stiffener and cooling fan to flywheel Remove Flywheel 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 1 Use a flywheel strap wrench or holding tool to hold flywheel and loosen screw securing flywheel to crankshaft 2 Remove screw and washer 3 Use a puller to remove flywheel from crankshaft 4 Remove woodruff key from crankshaft Inspection Inspect flywheel for cracks and
49. d in 0 25 mm 0 010 in and 0 50 mm 0 020 in oversize Replacement pistons include 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 reuse old rings Some important points to remember when servicing piston rings 1 Cylinder 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 Top and center compression ring end gap clearance is 0 30 0 55 mm 0 011 0 021 in with maximum wear limit of 0 94 mm 0 037 in 5 After installing new compression top and middle rings on piston make sure ring to groove side clearance is 0 04 0 08 mm 0 0015 0 0031 in 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 To instal
50. dapter lead connections are should be illuminated and 1 of 4 status lights may be not location specific on as well This does not represent condition of part 4 Connect remaining black lead from tester to 1 outer 4 Press TEST button until a click is heard and then AC terminal on rectifier regulator release Momentarily 1 of 4 status lights will 5 Plug tester into proper AC outlet power for tester illuminate indicating condition of part being used Turn on power switch POWER light should be illuminated and 1 of 4 status lights may be on as well This does not represent condition of part 6 Press TEST button until a click is heard and then release Momentarily 1 of 4 lights will illuminate indicating partial condition of part Condition Conclusion 20 25 amp 15 amp OK green light comes on and stays steady Disconnect tester black lead Part is good and may be used attached to 1 AC terminal and reconnect it to other AC terminal Repeat test If OK green light comes on again part is good and may be used NOTE A flashing LOW light can also occur as Rectifier regulator is faulty and should not be used a result of an inadequate ground lead connection Make certain connection location is clean and clamp is secure Other lights come on 36 KohlerEngines com 62 690 02 Rev D 15 20 25 Amp Battery Charging Systems Electrical System NOTE Always zero ohmmeter on each scale before testing to en
51. e actuation Hole B is used for Inner Pull control cable actuation 1 Connect choke linkage to appropriate hole in choke lever and secure with small clip 2 Connect throttle linkage to appropriate hole in throttle lever and secure with small clip Install Fuel Pump 1 Install fuel pump with hoses to control bracket if removed earlier Torgue mounting screws to 8 0 12 1 N m 71 107 in Ib into new holes or 6 0 9 0 N m 53 80 in Ib into used holes 2 Connect outlet fuel line to carburetor inlet and secure with a clamp 3 Install pulse hose and inlet hoses in their proper locations Adjusting Governor 1 Position governor lever so clamping area is inboard but completely on knurled area of governor cross shaft 2 Move governor lever toward carburetor as far as it will go wide open throttle and hold in position 3 Insert a long thin rod or tool into hole on cross shaft and rotate shaft clockwise viewed from end as far as it will turn then torque nut to 7 3 N m 65 in Ib 4 Ensure correct color springs are used Connect governor spring with long looped end to inner hole on governor lever and control bracket Connect governed idle spring to outer governor lever hole and control bracket Long end of each spring must be toward governor lever Make sure springs do not contact valley baffle KohlerEngines com 67 Reassembly Governor Spring RPM Chart Install Oil Filter and Add Oil to Crank
52. e discharge CD coil Ignition timing and spark remains constant regardless of engine speed Timing of spark is controlled by location of flywheel magnet group as referenced to engine TDC A typical fixed ignition system consists of e 1 magnet assembly which is permanently affixed to flywheel e 2 electronic capacitive discharge ignition modules which mount on engine crankcase e 1 kill switch or key switch which grounds modules to stop engine e 2 spark plugs Wire Diagram 15 20 25 Amp Regulated Battery Charging System with Fixed Timing Four Pin Connector rad CHI L A Blue B Red C Green D Violet Charging E White Ignition Kill F Connector G Battery H Battery Positive I Battery Negative J Starter K Rectifier Regulator L Oil Sentry Flywheel Stator Pe M Spark Plug s N Assembly o Ignition Module s P Carburetor Intake Manifold Rectifier Regulator Q Screw R Starter Solenoid Stud S Ground T Connector Starter Solenoid White U Tang V AC Charging Leads W Polarity Ribs X Solenoid Lead 32 KohlerEngines com 62 690 02 Rev D Electrical System Digital Spark Advance Ignition DSAI System This system uses a digital microprocessor which is located in ignition modules Ignition timing varies depend
53. ear is positioned outward in 6 o clock position inside crankcase 5 Orient flat of oil pump gear to match position of flat on camshaft Install oil pan to crankcase Carefully seat camshaft and crankshaft into their mating bearings Rotate crankshaft slightly to help oil pump and governor gears mesh 6 Lightly oil threads and install screws securing oil pan to crankcase Torque fasteners in sequence shown to 27 N m 238 in Ib Check Crankshaft End Play Set engine on base and use a dial indicator to check crankshaft end play to 0 30 1 50 mm 0 011 0 059 in KohlerEngines com 59 Reassembly Cyli nder Head Components A Gasket B Valve C Cylinder Head D Pipe Plug E Guide Plate F Spacer G Washer H Spark Plug I Valve Stem Seal J Valve Spring K Valve Spring Retainer L Hydraulic Lifter M Valve Spring Keeper N Push Rod o Rocker Arm P Rocker Arm Pivots Q Rocker Stud R Valve Cover Seal S Valve Cover T Grommet Install Breather 1 60 Make sure sealing surfaces of crankcase and breather cover are clean and free of any nicks or burrs Do not scrape surfaces as this could result in leakage Install breather chamber gasket as shown Assemble and install breather assembly components as illustrated Make sure filter does not extend above top surface and all parts are properly aligned Install screws and torque to 5 7 N m 51 in Ib following seguence Lightly oil
54. eck adjustment Proper valve clearance is 0 101 0 152 mm 0 004 0 006 in c Repeat procedure for other valve on this side Non Bled Lifters when cylinder heads and lifters are not removed a Turn 1 rocker arm adjusting nut from side 1 down until push rod is snug but can be rotated with drag This is 0 lash b Mark or note setting of adjustment nut then turn tighten adjuster nut 4 complete revolutions clockwise plus one flat of nut 1 6 turn or a total of 4 1 6 turns KohlerEngines com 61 Reassembly c Hold adjuster nut in this position and tighten locking setscrew Torque setscrew to 7 3 N m 65 in Ib d Repeat procedure for other valve on this side 4 Viewed from PTO end rotate crankshaft 270 3 4 turn counterclockwise and align crankshaft keyway with cylinder 2 which now puts that cylinder at TDC on compression stroke 5 Repeat steps 3 5 for setting valve clearance on cylinder 2 6 Rotate crankshaft to check for free operation of valve train Check for clearance between valve spring coils at full lift or bending of push rod s can occur Minimum allowable clearance is 0 25 mm 0 010 in Check Assembly Rotate crankshaft a minimum of two revolutions to check assembly and overall proper operation Check if engine can be turned over completely and compression is noted If it cannot locks up at some point return piston to TDC between intake and exhaust strokes first for one cylinder and t
55. ed expanded several times 1 Remove oil cooler mounting screws Do not lose any washers if used 2 Loosen clamps and disconnect hoses from oil cooler Remove Oil Filter Housing 1 Disconnect fuel shut off solenoid lead 2 Remove fuel inlet hose from carburetor Properly contain any remaining fuel 3 Remove carburetor and linkages as an assembly 4 Remove carburetor gasket 5 Carburetor and linkages can be separated as necessary Remove Oil Sentry if equipped 1 Disconnect lead from Oil Sentry switch 2 Remove Oil Sentry switch from oil pan Remove Baffles and Intake Manifold 1 Remove screws securing valley baffles to cylinder heads and backing shroud assembly 2 Remove screws securing outer cylinder baffles in place 3 Remove screws securing intake manifold to cylinder heads Cut any wire ties that secure wiring harness or leads to intake manifold 4 Remove intake manifold and gaskets 44 KohlerEngines com NOTE Further disassembly of oil filter housing assembly is not required unless being serviced individually Follow substeps a b and c 1 Remove screw securing oil filter housing and individual O rings to crankcase Carefully separate parts Perform following only if oil filter housing assembly requires individual servicing a Remove nipple from cup and oil filter housing b Remove oil filter cup and spring from housing c Remove rubber valve and spring from
56. er 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 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 62 690 02 Rev D c Install brush springs and snap on retainer caps Starter System 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 lb and brush holder 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 ga
57. f 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 A 11 mm 0 433 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 that clearance be accurately checked This step is often overlooked and if piston thrust face to cylinder bore running clearance is not within 0 033 0 071 mm 0 0013 0 0028 in engine failure will usually result Use following procedure to accurately measure piston to bore clearance 1 Use a micrometer and measure diameter of piston 11 mm 0 433 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 62 690 02 Rev D KohlerEngines com 55 Reassembly Crankcase Componenis KL an i
58. faulty carburetor Refer to Carburetor No fuel flow from fuel line Check fuel tank cap vent fuel pickup screen in line filter shut off valve and fuel line Correct any observed problem and reconnect line Fuel line condition Check for a clogged fuel line If fuel line is unobstructed check for overfilled crankcase and or oil in pulse line If checks don t reveal cause of problem replace pump 62 690 02 Rev D KohlerEngines com 21 Fuel System CARBURETOR y burns Ch Do not fill fuel tank while engine is hot or A WARNING running Explosive Fuel can cause fires and severe 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 Two Barrel Carburetor Components y Carburetor Body Idle Speed Idle Speed A Subassembly B Screw C Spring D Screw E Ground Lead Retaining Slow Jet Slow Jet O Ring 3 Washer G RightSide 4 Left Side I Slow Jet 9 Fuel Bowl O Ring Fuel O Ring Fuel K Bowl Upper L Bowl Lower M Drain Screw N Bowl Screw O Fuel Solenoid P Sealing Washer Q Float R Pin S Screw T Float Clip U Float Valve V Main Nozzle w Main Nozzle X
59. 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 engine 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 di
60. ffected test ignition modules and connections but also check white kill lead connection for affected DSAI module DSAI only 34 KohlerEngines com 62 690 02 Rev D Electrical System Test for Spark NOTE If 2 testers are available testing can be performed simultaneously for both cylinders However if only 1 tester is available 2 individual tests must be performed Side not being tested must have spark plug lead connected or grounded Do not crank engine or perform tests with 1 spark plug lead disconnected and not grounded or permanent system damage may occur 1 With engine stopped disconnect 1 spark plug lead Connect spark plug lead to post terminal of spark tester and attach tester clip to a good engine ground 2 Crank engine over establishing a minimum of 550 600 RPM and observe tester s for spark 3 Repeat spark test on opposite cylinder if cylinders are being tested individually Condition Possible Cause Conclusion One side is not firing Wiring and Connections Check all wiring connections and terminals on that side If wiring is okay replace ignition module and retest for spark Tester shows spark but engine Spark Plug s Try new spark plug s misses or won t run on that cylinder Neither side is firing Ignition Switch Recheck position of ignition switch and check for shorted kill lead Both cylinders have good spark but Spark Plug s Install new spark plug s and retest engine runs p
61. 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 Rectifier Regulator and Wiring Harness 1 Disconnect plug from rectifier regulator If B center lead must be removed from plug use a small flat tool to bend locking tang Then remove lead 2 Remove mounting screws securing rectifier regulator to backing shroud assembly Note location of ground lead If rectifier regulator is not being replaced it may remain mounted to backing shroud assembly 3 Remove screws securing stator to crankcase and carefully separate stator wires from molded clips 4 Unhook wiring harness from molded clips if it is being serviced separately Remove Backing Shroud Assembly Remove mounting screws securing backing shroud assembly to crankcase Remove Spark Plugs Remove spark plug from each cylinder head KohlerEngines com 45 Disassembly Inspection and Service Cylinder Head Components C A Gasket B Valve C Cylinder Head D Pipe Plug E Guide Plate F Spacer G Washer H Spark Plug I Valve Stem Seal J Valve Spring K Valve Spring Retainer L Hydraulic Lifter M Valve Spring Keeper N Push Rod o Rocker Arm P Rocker Arm Pivots Q Rocker Stud R Valve Co
62. found to be in bad condition 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 valve 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 if valve stem or guide is responsible for excessive clearance Maximum I D wear on intake valve guide is 7 135 mm 0 2809 in and 7 159 mm 0 2819 in for 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 48 KohlerEngines com 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 followin
63. g 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 interference 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 Seals These engines use valve stem seals on intake and exhaust valves Always use new seals when valves are removed from cylinder head Seals should also be replaced if deteriorated or damaged in any way Never reuse an old seal 62 690 02 Rev D Breather Oil Pan Components Disassembly Inspection and Service A Oil Pan B Gerotor Gears C Oil Pump O Ring D Oil Pump Housing E Relief Valve Baffle Pickup Tube G Inlet Seal H Pickup Screen l Drain Plug J en K oil Pan Gasket L Dipstick M Dipstick Tube
64. gnet and ignition module Loosen screws enough to allow magnet to pull module down against feeler gauge 6 Torque screws to 6 2 N m 55 in Ib into new holes or 4 0 N m 35 in Ib into used holes 7 Repeat steps 4 through 6 for other ignition module 8 Rotate flywheel back and forth checking for clearance between magnet and ignition modules Make sure magnet does not strike modules Check gap with a feeler gauge and readjust if necessary Final Air Gap 0 280 0 330 mm 0 011 0 013 in 9 Make sure leads are under molded clip on starter side 62 690 02 Rev D External Engine Components Reassembly Install Outer Cylinder Baffles 1 Install outer cylinder baffles Make sure spark plug lead is routed through corresponding opening in each baffle Start each screw Torque M6 shoulder screws going through backing shroud assembly into extruded holes in baffles to 4 0 N m 35 in Ib into new holes or 2 0 N m 18 in Ib into used holes 62 690 02 Rev D A Oil Filter B Oil Filter Nipple C Oil Filter Cup D Valve Spring E Cup Spring F Valve G Oil Filter Housing H Valley Baffle I Outer Cylinder Baffle J Electric Starter K Cylinder Shroud L Blower Housing M Fixed Guard N Oil Sentry o O Ring P Pin Q Fitting R Oil Cooler S Hose T Hose Clamp U Gasket V Carburetor WwW Intake Manifold 2 Torque M6 screws going into cylinder head and crankcase to 10 7 N m
65. gnition on these engines Use of any other tester can result in inaccurate findings Battery on unit must be fully charged and properly connected before performing tests a battery that is hooked up or charged backward will crank engine but it won t have spark Be certain drive is in neutral and all external loads are disconnected e Hand tachometer e Ignition tester e Automotive timing light e Multi meter digital Specifications Required e 0 76 mm 0 03 in Test Ignition Systems NOTE If engine starts or runs during testing you may need to ground kill lead to shut it down Because you have interrupted kill circuit it may not stop using switch Isolate and verify trouble is within engine 1 Locate connectors where wiring harnesses from engine and equipment are joined Separate connectors and remove white kill lead from engine connector Rejoin connectors and position or insulate kill lead terminal so it cannot touch ground Try to start engine to verify whether reported problem is still present Condition Possible Cause Conclusion Problem goes away Electrical System Check key switch wires connections safety interlocks etc Problem persists Ignition or Electrical System Leave kill lead isolated until all testing is completed Identify white kill lead of engine wiring harness connector Establish a connection to a known good ground location Engine should kill completely If not or only one cylinder is a
66. gs and Lever 1 Unhook governed idle and governor springs from controls on main bracket and governor lever Note color location and position of each 2 Disconnect throttle linkage and dampening spring from governor lever at small bushing 3 Carefully pry off pal nut remove washers note assembly order and disconnect choke linkage from pivot lever Do not lose any parts Secure remaining pivot parts with tape to avoid losing them Always use a new pal nut during reassembly 4 If fuel pump is being removed with bracket disconnect pulse vacuum hose and outlet fuel hose from pulse pump Properly contain any remaining fuel 5 Remove lower mounting screw going into intake manifold and remove main control bracket 6 Loosen nut and remove governor lever from cross shaft KohlerEngines com 43 Disassembly Inspection and Service Remove Carburetor Remove Oil Cooler A 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 New clamps are recommended any time disassembly is performed or if clamps have been loosen
67. hen other waiting ten minutes to allow lifters to bleed down then check for compression again Install Valve Covers Oil Cooler Filter Components 1 Make sure sealing surfaces are clean and free of any nicks or burrs 2 Install and properly seat seal onto each valve cover 3 Install valve covers on same side as they were originally installed 4 Install anew grommet on each valve cover mounting screw Start each screw into hole 5 Check position of each cover and seal then torque screws to 13 6 N m 120 in Ib Install Spark Plugs 1 Check gap using wire feeler gauge Adjust gap to 0 76 mm 0 030 in 2 Install plug into cylinder head 3 Torque plug to 27 N m 20 ft Ib 62 KohlerEngines com A Oil Filter B Oil Filter Nipple C Cup D Valve Spring E Cup Spring F Oil Filter Valve G Oil Filter Housing H Pin l O Ring J Fitting K Hose Clamp L Hose M Oil Cooler 62 690 02 Rev D Install Oil Filter Housing Assembly Reassemble oil filter housing if disassembled previously Reassembly 1 Install small spring onto rubber valve and insert small end through corresponding hole in cup until properly seated 2 Install larger spring into filter housing 3 Insert oil filter cup aligning cutout with corresponding section in housing 4 Install nipple in housing and torque to 18 N m 159 in Ib Installation 1 Make sure all sealing surfaces are c
68. ickup screen mounting screw to 10 7 Nm 95 in Ib into new hole or 7 3 N m 65 in Ib into used hole 62 690 02 Rev D Crankcase Components Disassembly Inspection and Service Remove Camshaft 62 690 02 Rev D i D AL He S H IAG EN N S i Ir B j PA E n ce EF n ATT pe 3 m if 9 i pE A B A SRL O 97 No CO A Camshaft B Locking Tab C Regulating Pin D Governor Gear E Cross Shaft F Lifter Feed Cover Gasket G Lifter Feed Cover H Governor Yoke l Crankshaft J Connecting Rod End Cap K Connecting Rod L Piston Pin M Piston Pin Retainer N Piston o Piston Ring Set P Oil Seal Q Crankshaft Bearing Flywheel Remove camshaft and shim if used Inspection Check lobes of camshaft for wear or damage Inspect cam gear for badly worn chipped or missing teeth Replacement of camshaft will be necessary if any of these conditions exist 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 ridge before attempting to remove piston Cylinders are 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 proced
69. il 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 Clean area around oil filter remove filter wipe off mounting surface Reinstall drain plug and torque to 21 4 N m 16 ft lb 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 Apply a thin film of clean oil to rubber gasket on new filter Refer to instructions on oil filter for proper installation Fill crankcase with new oil Level should be at top of indicator on dipstick Reinstall oil fill cap dipstick and tighten securely Start engine check for oil leaks Stop engine correct leaks Recheck oil level Dispose of used oil and filter in accordance with local ordinances 62 690 02 Rev D OIL COOLER NOTE Oil cooler is mounted under cylinder shroud Removal of cylinder shroud is necessary to access oil cooler 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 yo
70. ind a Kohler authorized dealer visit KohlerEngines com or call 1 800 544 2444 U S and Canada This engine should be operated in its original configuration below 1219 meters 4000 ft as damage may occur if high altitude carburetor kit is installed and operated below 1219 meters 4000 ft 62 690 02 Rev D GOVERNOR Governor System Governed speed setting is determined by position of throttle control It can be variable or constant depending on engine application Governor is designed to hold engine speed constant under changing load conditions Most engines are equipped with a centrifugal flyweight mechanical governor Governor gear flyweight mechanism of mechanical governor is mounted inside crankcase and is driven off gear on camshaft Governor Components r 8 NE B N Ko N Ee Nar DU G co Inside Engine AN U A Throttle Lever B Throttle Linkage C Nut D Governor Arm E Governor Spring Governed Idle Spring G Cross Shaft H Flyweight l Regulating Pin J Governor Gear This governor design works as follows Governor Adjustments e Centrifugal force acting on rotating governor gear assembly causes flyweights to move outward as speed increases Governor spring tension moves them inward as speed decreases As flyweights move outward they cause regulating pin to move outward Regulating pin contacts tab on cross shaft causing shaft to rotate One end of
71. ine starts hard runs rough or stalls at idle speed Low idle fuel mixture some models speed improperly adjusted Adjust low idle speed tab then adjust low idle fuel needle Engine runs rich indicated by black sooty exhaust smoke misfiring loss of speed and power governor hunting or excessive throttle opening Clogged air cleaner Clean or replace air cleaner Choke partially closed during operation Check choke lever linkage to ensure choke is operating properly Low idle fuel mixture is improperly adjusted Adjust low idle fuel needle some models Float level is set too high Adjust float according to Float Replacement Procedure Dirt under fuel inlet needle Remove needle clean needle and seat and blow with compressed air Bowl vent or air bleeds plugged Remove low idle fuel adjusting needle Clean vent ports and air bleeds Blow out all passages with compressed air Leaky cracked or damaged float Submerge float to check for leaks Engine runs lean indicated by misfiring loss of speed and power governor hunting or excessive throttle opening Low idle fuel mixture is improperly adjusted Adjust low idle fuel needle some models Float level is set too low Adjust float according to Float Replacement Procedure Idle holes plugged dirt in fuel delivery channels Remove low idle fuel adjusting needle Clean main fuel jet and
72. ing upon engine speed with this system There are 2 inductive style ignition modules that control ignition timing based on engine RPM A typical DSAI application consists of e 1 magnet assembly which is permanently affixed to flywheel e 2 inductive 12 volt ignition modules which mount on engine crankcase e 1 12 volt battery which supplies current to ignition modules e 1 kill switch or key switch which grounds spark advance module to stop engine e 2 spark plugs Wire Diagram 15 20 25 Amp Regulated Battery Charging System with DSAI Ignition and Four Pin Connector 7 LSS R S S 1 a fe fe S Ah amp f pr o A Blue B Red C Green D Violet E White F Black G Connector H Polarity Ribs l Battery J Battery Positive K Battery Negative L Starter Solenoid Stud M Starter Solenoid Tang N Starter o Oil Sentry P Rectifier Regulator Q Rectifier Regulator R Spark Plug s S Ignition Module s T Module Mounting Connector Screw U Flywheel Stator V Carburetor W Ground X White Assembly AC Charging Leads Y Spark Plug Lead Z Black Ground AA Red B AB White Shut Off AC Solenoid Lead AD P eon u 62 690 02 Rev D KohlerEngines com 33 Electrical System Electronic Ignition Systems Tests Special Tools Required NOTE Ignition tester must be used to test i
73. inimum 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 62 690 02 Rev D Electrical System ELECTRONIC IGNITION SYSTEMS Ignition System Components Kill Switch A Off Position of Air Gap Key Switch C Flywheel Magnet E Spark Plug F Ignition Modules There are 2 different types of ignition systems used on these engines All systems use an ignition module which energizes spark plug Difference in system is in way ignition timing is triggered Both ignition systems are designed to be trouble free for life of engine Other than periodically checking replacing spark plugs no maintenance or timing adjustments are necessary or possible Mechanical systems do occasionally fail or break down Refer to Troubleshooting to determine root of a reported problem Reported ignition problems are most often due to poor connections Before beginning test procedure check all external wiring Be certain all ignition related wires are connected including spark plug leads Be certain all terminal connections fit snugly Make sure ignition switch is in run position KohlerEngines com 31 Electrical System Fixed Ignition System This system uses a capacitiv
74. install end play checking tool and recheck end play Install Oil Pan Seal and Crankshaft Bearing PTO If bearing was removed in servicing install a new bearing using an arbor press and driver 1 Make sure oil pan bore for bearing is clean dry and free of nicks or burrs 2 Press crankshaft bearing PTO in place with notch oriented in 12 o clock position using an arbor press and driver Make sure bearing is fully seated against flange 3 Apply a light coat of clean engine oil to inner surface of bearing Oil Seal Details Gee ITS A 3 0 mm 0 118 in B Oil Seal 1 Check to make sure there are no nicks or burrs in crankshaft seal bore of oil pan 2 Lightly oil outside diameter of oil seal 3 Install oil seal into oil pan using a seal driver Make sure oil seal is installed straight and true in bore to depth shown Oil Pump Assembly Oil pump is mounted inside oil pan If service was required and oil pump was removed refer to Disassembly Inspection and Service procedure 62 690 02 Rev D Reassembly Install Oil Pan Assembly Torque Sequence 1 Make sure sealing surfaces of oil pan and crankcase are clean dry and free of any nicks or burrs Install a new O ring in oil pan 2 Install a new oil pan gasket onto crankcase 3 Make sure oil pump and oil pick up are installed in oil pan 4 Ensure end of locking tab washer on governor g
75. iously disconnected Install carburetor with linkages attached as an assembly Install Governor Lever Install governor lever onto governor shaft and connect throttle linkage with black clip Do not tighten governor lever at this time Install Control Bracket and Air Cleaner Assembly Torque Sequence 3 71 O11 5 2 6 C O 4 8 1 Position control bracket assembly onto intake manifold bosses aligning mounting holes 2 Install a new air cleaner elbow gasket onto mounting studs 3 Slide air cleaner assembly onto carburetor mounting studs attach ground lead with star washer if used and finger tighten nuts Align forward mounting holes in base with mounting holes bosses of intake manifold and control bracket then start screws Check positions of all parts then torque nuts to 7 9 N m 70 in Ib in sequence shown and screws to 9 9 Nm 88 in Ib 4 Connect breather hose to fitting on outlet of air cleaner and connect fuel solenoid lead 5 Connect formed vent hose to air cleaner housing and vent port on carburetor 6 Connect choke link to control pivot pin Reinstall washer and secure with a new push on pal nut 62 690 02 Rev D Cable Control Details A Hole A B Hole B If individual throttle choke lever control linkages were disconnected during disassembly reconnect them based on operating direction of control cables to be used Hole A is used for Outer Pull control cabl
76. ith mounting screws Lower section should fit under outer baffle Torque M6 screws going into cylinder head to 10 7 N m 95 in Ib for new holes or 7 3 N m 65 in Ib for used holes Start upper M6 screws only if main control bracket rear supports attach to these screws Torque M6 screw going into lower blower housing mounting clip to 2 5 N m 22 in Ib Throttle Lever Throttle Linkage Nut D Governor Arm Governor Spring Governed Idle Spring I Cross Shaft Governor Lever Choke Cable Clamp Control Pivot Pin Pal Nut L Choke Linkage Ss m gt ze NU Choke Return Spring Choke Bracket OAO O Choke Lever 66 KohlerEngines com 62 690 02 Rev D Install Carburetor Reassembly Install Throttle and Choke Linkages A WARNING Explosive Fuel can cause fires and severe 7 burns Gh 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 1 Install a new carburetor gasket onto intake manifold with tab up Make sure all holes align and are open 2 Connect throttle and choke linkages to carburetor if they were prev
77. ked cooling fins or from inadequate or contaminated lubrication 54 KohlerEngines com 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 then select nearest suitable oversize of either 0 25 mm 0 010 in or 0 50 mm 0 020 in Resizing to these oversizes will allow usage of available oversize piston and ring assemblies Initially resize using a boring bar then use following procedures for honing cylinder 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 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 edge of each stone positioned even with lowest edge of bore
78. kirt at right angles to piston pin 10 KohlerEngines com 62 690 02 Rev D Specifications CLEARANCE SPECIFICATIONS CV940 CV960 CV980 CV1000 Valves and Valve Lifters Hydraulic Valve Lifter to Crankcase Running Clearance 0 012 0 050 mm 0 0004 0 0019 in Intake Valve Stem to Valve Guide Running Clearance 0 038 0 076 mm 0 0015 0 0030 in Exhaust Valve Stem to Valve Guide Running Clearance 0 050 0 088 mm 0 0020 0 0035 in Intake Valve Guide I D New 7 038 7 058 mm 0 2771 0 2779 in Max Wear Limit 7 135 mm 0 2809 in Exhaust Valve Guide I D New 7 038 7 058 mm 0 2771 0 2779 in Max Wear Limit 7 159 mm 0 2819 in Guide Reamer Size Standard 7 048 mm 0 2775 in 0 25 mm O S 7 298 mm 0 2873 in Nominal Valve Face Angle 45 3Values are in Metric units Values in parentheses are English equivalents 62 690 02 Rev D KohlerEngines com 11 Specifications GENERAL TORQUE VALUES English Fastener Torque Recommendations for Standard Applications Bolts Screws Nuts and Fasteners Assembled Into Cast Iron or Steel O Grade 2 or 5 Fasteners Into Aluminum OQ Size Grade 2 Grade 5 Grade 8 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 2
79. l new piston rings proceed as follows 1 Oil control ring bottom groove Install expander and then rails Make sure ends of expander are not overlapped 62 690 02 Rev D 2 Middle compression ring center groove Install center ring using a piston ring installation tool Make sure identification mark is up or colored dye stripe if contained is to left of end gap 3 Top compression ring top groove Install top ring using a piston ring expander Make sure identification mark is up or colored dye stripe if contained is to left of end gap Remove Crankshaft NOTE If crankpin is reground visually check to ensure that fillet blends smoothly with crankpin surface Carefully pull crankshaft from crankcase Note thrust washers and shims if used Inspection and Service Crankshaft Components and Details A Self Tapping Screw B Flat Washer C Plug D Crankshaft E Fillet Must Blend Smoothly with Bearing Journal Surface F High Point from Fillet Intersections G 45 Minimum H This Fillet Area Must Be Completely Smooth Inspect gear teeth of crankshaft If teeth are badly worn chipped or some are missing replacement of crankshaft will be necessary 62 690 02 Rev D Disassembly Inspection and Service Inspect crankshaft bearing surfaces for scoring grooving etc Replaceable bearings are used in crankshaft bore of oil pan and or crankcase
80. l seal 3 Install oil seal into crankcase using a seal driver Make sure oil seal is installed straight and true in bore and tool bottoms against crankcase Install Lifter Feed Chamber Gaskets and Cover 1 Install lifter feed chamber gasket followed by lifter feed cover over lifter feed chamber 2 Install screws Make sure all parts are properly aligned Torgue screws to 6 2 N m 55 in Ib into new holes or 4 0 N m 35 in Ib into used holes Install Crankshaft Bearing flywheel If bearing was removed in servicing install a new bearing using an arbor press and driver 1 Make sure crankcase bore for bearing is clean dry and free of nicks or burrs 2 Press flywheel side main bearing in place with notch oriented in 12 o clock position using an arbor press and driver Make sure bearing is fully seated against flange and oil feed hole is open in crankcase 3 Apply a light coat of clean engine oil to inner surface of main bearing 62 690 02 Rev D Reassembly Install Governor Shafts Seal and Governor Gear Install Crankshaft Governor Components and Details Carefully slide flywheel end of crankshaft through bearing in crankcase Install Connecting Rods with Pistons and Rings Piston Details A B C Top of Piston NOTE Cylinders are numbered on crankcase Make Seal Depth sure to install piston connecting rod and end A Crankcase Surface
81. lean and all dowel pins are in position Install or check new O rings are around all oil filter adapter dowel pins 2 Install oil filter housing assembly and secure with M8 screw Make sure housing is flat on crankcase and all O rings remain in position Torque screw to 24 4 Nm 216 in lb 3 Oil filter may be installed now or upon completion of engine assembly Install Intake Manifold Torque Sequence 1 Install new intake manifold gaskets so notched section is inward and points toward flywheel side 2 Mount intake manifold to cylinder heads Make sure gaskets remain in proper position Torque screws in 2 stages using sequence shown first to 16 9 N m 150 in Ib finally to 22 6 N m 200 in lb 3 Install carburetor mounting studs into intake manifold if previously removed Use nuts locked flange to flange and tighten each stud until bottomed tight 62 690 02 Rev D Reassembly Flywheel Ignition Components A Special Washer B Debris Screen C Hex Stud D Stiffener E Fan F Flywheel Screw G Ignition Module H Washer I Magnet J Wire Harness Clamp K Flywheel L Stator M Rectifier Regulator N Backing Shroud o Woodruff Key KohlerEngines com 63 Reassembly Install Backing Shroud Assembly NOTE New hose clamps are recommended for reassembly or if clamps have been loosened expanded several times to avoid leakage 1
82. lete 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 it is above sniff for gasoline 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
83. lower end of breather hose and install into hole in breather assembly Cover should be situated between 2 raised rings of hose Install Hydraulic Lifters NOTE Hydraulic lifters should always be installed in same position as they were disassembled Exhaust lifters are located on output shaft side of engine while intake lifters are located on fan side of engine Cylinder numbers are embossed on top of crankcase and each cylinder head 1 Refer to Disassembly Inspection and Service for lifter preparation bleed down procedures 2 Apply camshaft lubricant to bottom surface of each lifter Lubricate hydraulic lifters and lifter bores in crankcase with engine oil Do not prime lifters 3 Note mark or tag identifying hydraulic lifters as either intake or exhaust and cylinder 1 or cylinder 2 Install hydraulic lifters into their appropriate location in crankcase Do not use a magnet KohlerEngines com 62 690 02 Rev D Valve Stem Seals These engines use valve stem seals on intake and exhaust valves Always use new seals whenever valves are removed from cylinder head Seals should also be replaced if worn or damaged 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 in order listed below using a valve spring compressor e Intake and exhaust valves e Valve spring ret
84. ns and procedures when installing flywheel 64 KohlerEngines com 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 crankshaft keyway Make sure key is properly seated and parallel with shaft taper 2 Install 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 to 67 8 N m 50 ft Ib Install Ignition Modules 1 Rotate flywheel to position magnet away from ignition module bosses 2 Connect ground lead to single kill tab and install modules onto crankcase bosses so tab is away from you IN and spark plug lead should be towards you OUT Mount wiring harness clamp with loop UP on starter side inner module screw and route harness through it Attach rectifier regulator ground lead to outer screw 3 Slide modules up as far away from flywheel as possible and snug screws to hold them in position 4 Rotate flywheel to position magnet directly under 1 ignition module 5 Insert a 0 30 mm 0 012 in flat feeler gauge between ma
85. o 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 1 Cut a 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 on 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 62 690 02 Rev D Disassembly Inspection and Service Disassemble Cylinder Heads NOTE These engines use valve stem seals on intake and exhaust valves Use a new seal whenever valves are removed or if seal is deteriorated in any way Never reuse an old seal 1 Remove adjusters rocker arm pivots and rocker arms from cylinder head Remove pivot studs and guide plate as required 2 Compress valve springs using a valve spring compressor 3 Once valve spring is compressed remove following items e Valve spring keepers e Valve spring retainers e Valve springs e Valve spring caps e Intake and exhaust valves mark position e Valve stem seals 4 Repeat above procedure for other cylinder head Do not interchange parts from 1 cylinder head to another Inspection and Service Valve Details EXHAUST VALVE INTAKE VALVE Ike 2e amp INT B A ER
86. ole on cross shaft and rotate shaft clockwise viewed from end as far as it will turn then torque nut to 7 3 N m 65 in Ib oN 27 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 A Oil Filter Back Side Oil Cooler Cylinder Shroud E Oil Drain Plug F Oil Fill Tube Oil Fill Dipstick H Pressure Switch 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 Ifoil is low on indicator add oil up to top of indicator mark 5 Reinstall and secure dipstick 28 KohlerEngines com CHANGE OIL AND FILTER Change o
87. oorly or existing plug engine performance condition is questionable If problem persists check for timing advance DSAI only 1 cylinder has good spark and other Ignition Test ignition modules and cylinder has no or intermittent spark connections DSAI only Spark on both cylinders but power is Timing Advance Check for timing advance DSAI suspect only Test Timing Advance DSAI only 1 Make a line near edge of flywheel screen with a marking pen chalk or narrow tape 2 Connect an automotive timing light to cylinder that had good spark 3 Run engine at idle and use timing light beam to locate line on screen Draw a line on blower housing next to line on screen Accelerate to full throttle and watch for movement of line on screen relative to line on blower housing If both cylinders had good spark repeat test on other cylinder Condition Possible Cause Conclusion Line on screen did not move away Ignition Test ignition modules and from line on blower housing during connections acceleration Lines made on blower housing not 90 apart Test Ignition Modules and Connections DSAI only 1 Remove blower housing from engine Inspect wiring for any damage cuts bad crimps loose terminals or broken wires Check that connections are oriented properly on terminals of modules 2 Disconnect leads from ignition module s and clean all of terminals male and female with aerosol electric
88. ote preload of spring and discard removed parts Use a screw extractor easy out and remove original choke shaft bushing with old choke lever from carburetor housing Save bushing to use as a driver for installing new bushing Discard old lever Clean I D of both choke shaft bores as required Insert new bushing through new choke lever from outside and start bushing in outer shaft bore Position choke lever so protruding boss on carburetor housing is between 2 stops formed in choke lever KohlerEngines com 25 Fuel System 13 Turn old bushing upside down and use it as a driver to carefully press or tap new bushing into carburetor body until it bottoms Check that choke lever pivots freely without restriction or binding 14 Install new return spring onto new choke shaft so outboard leg of spring is behind formed stop on end of choke shaft Make sure it stays in this location during following step 15 Slide choke shaft and spring into carburetor Pivot preload shaft 3 4 turn counterclockwise with inner leg of spring against formed stop within choke lever as originally assembled Outer leg of spring must still be behind formed stop of choke shaft 16 Place a drop of Loctite 222MS on threads of each new screw Position and install new choke plate to flat side of choke shaft Start screws Close choke and check plate alignment within carburetor throat then tighten screws securely Do not overtighten 17 Check for
89. otor gears and oil pan recess for nicks burrs wear or any visible damage Inspect inlet seal for pickup tube in housing If any parts are worn or damaged replace seal oil pump or oil pan as required Reassembly Torque Sequence 50 KohlerEngines com Make sure recess in oil pan for oil pump gerotor gears is clean Lubricate oil pump gerotor gears with grease Lubriplate 100 or equivalent and install into recess Lightly lubricate with oil and install inlet seal into oil pump housing until it is fully seated Install O ring in groove of oil pump housing Use a small quantity of grease to hold it in place Lightly lubricate I D of inlet seal with oil and carefully insert end of pickup tube through seal into oil pump housing Install oil pump housing with pickup tube over oil pump boss and gears Position relief valve baffle on location 2 and location 3 Align all 3 screw locations Check alignment of parts and torque oil pump housing screws as specified using sequence below a Install fastener into screw location 1 and lightly tighten to position pump b Install fastener into screw location 2 and fully torque to recommended value c Install fastener into screw location 3 and fully torque to recommended value d Finish torquing fastener in screw location 1 to recommended value First Time Installation 10 7 N m 95 in Ib All Reinstallations 6 7 N m 60 in Ib Install and torque p
90. pped Hole casting 7 3 N m 65 in Ib New Extruded Hole sheet metal 4 0 N m 35 in Ib Used Extruded Hole sheet metal 2 0 Nm 18 in Ib Mounting Clip valley baffle 2 5 N m 22 in Ib Carburetor Intake Manifold and Air Cleaner Intake Manifold Mounting Fastener torque in 2 increments first to 16 9 N m 150 in Ib finally to 22 6 N m 200 in Ib 7 9 N m 70 in Ib 9 9 N m 88 in lb 2 5 0 3 N m 22 2 3 in lb Carburetor Air Cleaner Mounting Nut Air Cleaner Mounting Screw into intake manifold Fuel Bowl Screw Connecting Rod Cap Fastener torque in increments 11 3 N m 100 in Ib Control Bracket Mounting Screw into intake manifold from air cleaner 9 9 N m 88 in lb Crankcase Breather Cover Fastener 5 7 N m 51 in Ib Oil Drain Plug 21 4 Nm 16 ft Ib Dipstick Tube Screw 4 0 N m 35 in Ib 3Values are in Metric units Values in parentheses are English equivalents 4 Exceeding maximum angle of operation may cause engine damage from insufficient lubrication 5 Lubricate threads with engine oil prior to assembly S Any and all horsepower hp references by Kohler are Certified Power Ratings and per SAE J1940 8 J1995 hp standards Details on Certified Power Ratings can be found at KohlerEngines com 6 KohlerEngines com 62 690 02 Rev D Specifications TORQUE SPECIFICATIONS CV940 CV960 CV980 CV1000 Cylinder Head Fastener
91. pression 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 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 acce
92. r 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 62 690 02 Rev D Carbon Fouled gt 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 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 Battery Required Above 32 F 0 C 300 cca minimum 0 F to 32 F 18 C to 0 C 5 F to 0 F 21 C to 18 C 300 cca m
93. rectly 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 exhaust 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 18 KohlerEngines com 62 690 02 Rev D Troubleshooting COMPRESSION TEST For Command Twins A com
94. ric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 8 KohlerEngines com 62 690 02 Rev D CLEARANCE SPECIFICATIONS Specifications CV940 CV960 CV980 CV1000 Connecting Rod Crankpin End I D 70 F New Max Wear Limit 44 030 44 037 mm 1 7334 1 7337 in 0 070 mm 0 0028 in Connecting Rod to Crankpin Running Clearance New Max Wear Limit 0 030 0 055 mm 0 0012 0 0022 in 0 070 mm 0 0028 in Connecting Rod to Crankpin Side Clearance 0 30 0 59 mm 0 0118 0 0232 in Connecting Rod to Piston Pin Running Clearance 0 015 0 028 mm 0 0006 0 0011 in Piston Pin End I D 70 F New Max Wear Limit 19 015 19 023 mm 0 7486 0 7489 in 19 036 mm 0 7494 in Crankcase Governor Cross Shaft Bore D New Max Wear Limit 8 025 8 050 mm 0 3159 0 3169 in 8 088 mm 0 3184 in Crankshaft End Play free 0 30 1 50 mm 0 011 0 059 in Bore in crankcase New Without Main Bearing With Main Bearing Installed Max Wear Limit 50 00 50 025 mm 1 9685 1 969 in 45 040 45 145 mm 1 7732 1 7773 in 45 158 mm 1 7778 in Crankshaft to Sleeve Bearing crankcase Running Clearance New 0 040 0 167 mm 0 0015 0 0065 in Bore in oil pan New Without Bearing 50 025 50 00 mm 1 9694 1 9685 in Crankshaft to Sleeve Bearing in oil pan Running Clearance New 0 040 0 167 mm
95. rom air cleaner and formed vent hose from vent port on carburetor 2 Remove nuts and ground lead from mounting studs 3 Remove screws securing air cleaner and main control bracket to intake manifold bosses 4 Remove air cleaner as an assembly from engine 62 690 02 Rev D Disassembly Inspection and Service Remove Fuel Pump A WARNING Explosive Fuel can cause fires and severe P burns 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 Based on style of fuel pump used refer to following Pulse Style Fuel Pump Pulse style fuel pump is mounted to side of control bracket It may be removed separately or with bracket To remove separately 1 Remove mounting screws securing fuel pump to control bracket 2 Disconnect inlet outlet and pulse vacuum hoses and remove fuel pump Properly contain any remaining fuel Electric Fuel Pump Removal will be determined based on mounted location and application Disconnect lead connections fuel line connections and mounting hardware as required Properly contain any remaining fuel Remove Control Bracket Governor Sprin
96. rop 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 38 KohlerEngines com 62 690 02 Rev D SOLENOID SHIFT STARTERS When power is applied to starter electric solenoid moves drive pinion out onto drive sh
97. 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 59009 or 5910 are recommended for best sealing characteristics Kohler 25 597 07 S Loctite 5910 Loctite Ultra Black 598 Loctite Ultra Blue 587 Loctite Ultra Copper 5920 Spline Drive Lubricant Kohler 25 357 12 S 14 KohlerEngines com 62 690 02 Rev D Tools and Aids FLYWHEEL HOLDING TOOL ROCKER ARM CRANKSHAFT TOOL A flywheel holding tool
98. sket 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 lb 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 Condition To test solenoid hold in coil Function 1 Connect a 12 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
99. ssible 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 seating 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 repla
100. stand Install an oil pressure gauge Start engine and check to be certain oil pressure 20 psi or more is present Run engine at idle for 2 3 minutes then 5 6 minutes more between idle and midrange Adjust carburetor mixture settings as necessary as available 2 Adjust governed idle and high speed RPM to required settings Make sure maximum engine speed does not exceed 3900 RPM no load 62 690 02 Rev D 62 690 02 Rev D KohlerEngines com 69 70 KohlerEngines com 62 690 02 Rev D 62 690 02 Rev D KohlerEngines com 71 IU TEILT 2011 by Kohler Co All rights reserved 6 50531 9910 12 KohlerEngines com 62 690 02 Rev D 2
101. 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 62 690 02 Rev D Disassembly Inspection and Service 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 There are 2 measurements that should be taken perpendicular to each other at all 3 locations 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 water Use a strong detergent that is capable o
102. ston assembly is required Ring failure is usually indicated 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 52 KohlerEngines com 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 an
103. sure accurate readings Voltage tests should be made with engine running at 3600 RPM with no load Battery must be good and fully charged When problems occur in keeping battery charged or battery charges at high rate charging system or battery might be causing problems 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 Condition Conclusion Charge rate increases when load is applied Charging system is OK and battery was fully charged Charge rate does not increase when load is applied Test stator and rectifier regulator steps 2 and 3 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 more Stator is OK Rectifier regulator is faulty replace Voltage is less than 28 volts Stator is faulty replace Test stator further using an ohmmeter steps 3 and 4 3 With engine stopped measure resistance across stator leads using an ohmmeter Condition
104. t low idle speed to 1200 RPM Follow Low Idle Speed RPM Adjustment 2 Low idle fuel needle s setting place throttle into idle or slow position a Turn 1 low idle fuel adjusting needle out counterclockwise from preliminary setting until engine speed decreases rich Note position of needle Now turn adjusting needle in clockwise Engine speed may increase then it will decrease as needle is turned in lean Note position of needle Set adjusting needle midway between rich and lean settings b Repeat procedure on other low idle adjustment needle 3 Recheck adjust Low Idle Speed RPM to specified setting mian Speed RPM Adjustment With engine running move throttle control to fast 2 Turn inner adjustment screw outward to decrease or inward to increase RPM speed 3 Stop when desired RPM speed is obtained Carburetor Servicing A WARNING Wy Accidental Starts can cause severe injury or death Disconnect and ground spark plug lead s before servicing Before working on engine or equipment disable engine as follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery NOTE Main and slow jets are fixed and side specific and can be removed if required Fixed jets for high altitudes are available e Inspect carburetor body for cracks holes and other wear or damage e Inspect float for cracks holes and missing or damaged float
105. tabs Check float hinge and shaft for wear or damage e Inspect fuel inlet needle and seat for wear or damage e Inspect spring loaded choke plate to make sure it moves freely on shaft Float Replacement Overhaul Choke Repair NOTE Inlet needle center pin is spring loaded Make sure float rests against fuel inlet needle without depressing center pin If symptoms described in Troubleshooting Carburetor Related Causes indicate float level problems remove carburetor from engine to check and or replace float Use a float kit to replace float pin float valve clip and screw 62 690 02 Rev D 10 11 12 Fuel System Perform removal procedures for appropriate air cleaner and carburetor outlined in Disassembly Clean exterior surfaces of dirt or foreign material before disassembling carburetor Remove screws and carefully separate fuel bowl from carburetor Do not damage fuel bowl O rings Transfer any remaining fuel into an approved container Save all parts Fuel can also be drained prior to bowl removal by loosening removing bowl drain screw Remove screw and lift out old float pin and inlet needle Discard all of parts Seat for inlet needle is not serviceable and should not be removed Clean carburetor bowl and inlet seat areas as required To reassemble fuel bowl go to step 23 otherwise go to step 5 Carefully remove main jets from carburetor Note and mark jets by location for proper reassembly Main jets may
106. te 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 each push rod ball seats in its hydraulic lifter socket 3 Apply grease to contact surfaces of rocker arms and rocker arm pivots Install rocker arms rocker arm pivots and adjusters on cylinder head 1 Adjust Valve Clearance NOTE It takes two hands to make lash adjustment A clamping device or an assistant to hold lifter compressed while making adjustment will make process easier 1 Turn adjusters in rocker arms by hand clockwise down only enough to capture push rods in recesses 2 Rotate crankshaft to establish TDC on compression stroke for cylinder 1 Check for a Compression will be felt through spark plug hole b Keyway of crankshaft will be aligned with cylinder T c No rocker arm push rod movement if crankshaft is rotated slightly back and forth If they are moving rotate crankshaft one full revolution 3 Pre Bled Lifters a Apply downward pressure to push rod side of rocker arm to compress lifter and bottom internal plunger Several manual compressions may be necessary Hold in this position for step 3b b Insert a 0 127 mm 0 005 in feeler gauge between end of one valve and rocker arm Turn adjuster until a slight drag is felt Hold adjuster in this position and tighten locking setscrew Torque setscrew to 7 3 N m 65 in Ib After tightening rech
107. ted areas away from ignition sources A CAUTION Failure to utilize or reassemble debris screen as designed could x result in debris screen failure and serious personal injury 4 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 KohlerEngines com 62 690 02 Rev D MAINTENANCE INSTRUCTIONS Maintenance A WARNING w Accidental Starts can cause severe injury or death er Disconnect and ground spark plug lead s x before servicing Before working on engine or equipment disable engine as follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery Normal maintenance replacement 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 Weekly e Check filter minder Air Cleaner Intake Every 25 Hours or Annually e Service replace low profile precleaner Air Cleaner Intake Every 150 Hours e Replace low profile air cleaner element Air Cleaner Intake e Change oil Oil filter is recommended Lubrication System e Remove cooling shrouds and clean cooling areas Air Cleaner Intake
108. ted charging system 15 20 25 Amp Regulated Charging System Stator Stator is mounted on crankcase behind flywheel Follow procedures in Disassembly and Reassembly if stator replacement is necessary Rectifier Regulator NOTE When installing rectifier regulator take note of terminal positions and install plug correctly 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 backing shroud assembly To replace it disconnect plug remove mounting screws and ground lead Testing rectifier regulator may be performed as follows using appropriate rectifier regulator tester To test 20 25 amp rectifier regulators To test 15 amp rectifier regulators 1 Connect single lead adapter in between B center 1 Connect tester ground lead with spring clamp to terminal of rectifier regulator being tested and body of rectifier regulator being tested squared single end of tandem adapter lead 2 Connect tester red lead to B terminal of rectifier 2 Connect tester ground lead with spring clamp to regulator and 2 black tester leads to 2 AC terminals body of rectifier regulator 3 Plug tester into proper AC outlet power for tester 3 Connect red lead and 1 black lead to terminals on being used Turn on power switch POWER light open end of tandem a
109. ter at wiring harness or any electrical components Refer to Maintenance Schedule 62 690 02 Rev D Typical carbureted fuel system and related components include e Fuel tank and valve e Fuel lines e In line fuel filter e Fuel pump e Carburetor Fuel from tank is moved through in line filter and fuel lines by fuel pump Fuel then enters carburetor float bowl and is drawn into carburetor body and mixed with air This fuel air mixture is then burned in engine combustion chamber FUEL RECOMMENDATIONS Refer to Maintenance FUEL LINE Low permeation fuel line must be installed on carbureted Kohler Co engines to maintain EPA and CARB regulatory compliance FUEL SYSTEM TESTS Fuel System FUEL PUMP Some engines use a pulse style fuel pump or optional remote mounted electric fuel pump assembly Pumping action of pulse style pumps is created by oscillation of positive and negative pressures within crankcase This pressure is transmitted to pulse pump through rubber hose connected between pump and crankcase Pumping action causes diaphragm on inside of pump to pull fuel in on its downward stroke and to push it into carburetor on its upward stroke Two check valves prevent fuel from going backward through pump Fuel Pump Replacement NOTE Make sure orientation of new pump is consistent with removed pump Internal damage may occur if installed incorrectly To replace pulse pump follow these steps
110. 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 reguired Inspection Drive Pinion Check 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 guestionable KohlerEngines com 39 Starter System Armature Components and Details A A Commutator O D B Mica Insulation C Insulation Check D Armature Coil E Continuity Check 1 Clean and inspect commutator outer surface Mica insulation must be lower than commutator bars undercut to ensure proper operation of commutator 2 Use an ohmmeter 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 3 Check for continuity between armat
111. tor 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 62 690 02 Rev D 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 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 62 690 02 Rev D KohlerEngines com 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 comp
112. ur equipment manuals for more information Oil Sentry pressure switch is installed in oil pan pressure port On engines not equipped with Oil Sentry installation hole is sealed with a 1 8 27 N P T F pipe plug 62 690 02 Rev D Lubrication System Installation 1 Apply pipe sealant with Teflon Loctite PST 592 Thread Sealant or equivalent to threads of switch 2 Install switch into tapped hole in oil pan 3 Torque switch to 10 1 N m 90 in Ib Testing Compressed air a pressure regulator pressure gauge and a continuity tester are required to test switch 1 Connect 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 7 11 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 7 11 psi Tester should indicate a change to continuity switch closed down to 0 psi 4 Replace switch if it does not operate as specified KohlerEngines com 29 Electrical System SPARK PLUGS Inspection A cAUTION W Electrical Shock can cause injury Do not touch wires while engine is running Spark Plug Component and Details o Bo A Wire Gauge B Spark Plug
113. ure coil segments and commutator segments There should be no continuity If continuity exists between any 2 armature is bad 4 Check armature windings insulation for shorting Shift 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 40 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 KohlerEngines com 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 lever will be flush or below machined surface of 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
114. ures for other connecting rod and piston assembly Connecting Rods Offset stepped cap connecting rods are used in these engines Inspection and Service Check bearing area big end for excessive wear score marks running and side clearances 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 Always refer to appropriate parts information to ensure that correct replacements are used NOTE KohlerEngines com 51 Disassembly Inspection and Service Piston and Rings Inspection Piston and Rings Components and Details A Piston Ring B End Gap C Identification Mark D Piston E Top Compression F Center Ring Compression Ring G Rails H Expander N Oil Control Ring 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 pi
115. uretor 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 Carburetor 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
116. ver Seal S Valve Cover T Grommet Remove Valve Covers 1 Remove screw and grommet securing each valve cover 2 Remove valve cover and seal from each cylinder head Note locations of individual valve covers if they are different Remove Cylinder Heads and Hydraulic Lifters NOTE Exhaust lifters are located on output shaft side of engine while intake lifters are located on fan side of engine Cylinder head number is embossed on outside of each cylinder head 1 Loosen inner set screws and back off rocker arm adjusting nuts 2 Remove pipe plug from cylinder head to access screw in center location 3 Remove screws securing each cylinder head Note locations of washers and spacer 4 Mark position of push rods as either intake or exhaust and cylinder 1 or 2 Push rods should always be reinstalled in same positions 5 Carefully remove push rods cylinder head and head gasket 46 KohlerEngines com 6 Repeat procedure for other cylinder head 7 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 to base of each new lifter before it is installed Bleeding Lifters T
117. ver away from carburetor to limit its travel and check that governor spring is loose and not under any tension Turn high speed RPM adjustment screw counterclockwise if required until spring is loose 3 Hold governor lever away from carburetor so throttle lever is against idle speed RPM adjustment screw of carburetor Start engine and allow to warm up then adjust screw to set approximately 1200 RPM Check speed using a tachometer Turn adjustment screw inner clockwise in to increase or counterclockwise out to decrease speed 4 Release governor lever and check that throttle lever is in idle centered position Turn governed idle outer adjustment screw to obtain equipment manufacturer s recommended idle speed 1500 1800 RPM Governed idle speed RPM is typically 300 RPM approximate higher than low idle speed 5 Move throttle lever to wide open full throttle position and hold in this position Turn high speed screw to obtain intended high speed no load RPM Governed idle speed must be set before making this adjustment Low Idle Fuel Adjustment Adjustto Lean Adjustto Lean Midpoint s Midpoint a E a A m z M d Right Side Q Left Side 62 690 02 Rev D NOTE Engines will have fixed low idle or limiter caps on idle fuel adjusting needles Step 2 can only be performed within limits allowed by cap Do not attempt to remove limiter caps 1 Place throttle control into idle or slow position Adjus

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