Home

Caution: This document contains mixed page sizes (8.5 x 11 or 11 x

1. MEE eee OPTIONAL OPTIONAL LOAD P 2 297 Js Rig J d L OPTIONAL A4 0 5 2 gt Aci J6 H BTI TO GENSET SS ENABLE SWITCH HI CHOKE HEATER SEENOGTES r q VR2 tem T C4 NE B
2. 2 OPTIONAL 1 THE ENABLE SWITCH IS CUS TOMER PROVIDED USE 16 GA CU 1 ag OPTIONAL WIRE FOR CONNECTIONS 3 1 2 SEE THE SECTION TITLED GEN 20v E Ac J6 ERATOR FOR GENERATOR RE TO GENSET ENABLE SWITCH CONNECTIONS 7 HI rp CHOKE HEATER SEEN EA 3 FOR ISOLATED NEUTRAL RE CB2 T a 4 MOVE JUMPER W2 BETWEEN EE 1 13 AND 1 10 OPTIONAL ri C x QNO ze 4 LEAD L1 J4 CONNECTS TO J16 ej s E4 ncm a 5 LEAD L1 P4 2 CONNECTS TO J15 Mii 12 13 83 rosado 0 _ SEE NOTE re 2 p xe De VRI PMG L E T2 JA P4 22 7 7 Im LU 8 49495 6 9 1 SEE NOTE 1 52 TP of T
3. j SB s LOAD Fl FUSE SLOW BLOW gi ise 4 SPARK PLUGS ewes SERI p Jes FUEL PUMP OR FUEL SOL E2 120 CR6 RECTIFIER HI NEUTRAL CB4 CIRCUIT BREAKER THERMAL t GND 2 CIRCUIT BREAKER AC OUTPUT ut l 2 4 5 CAPACITOR P BATTERY 12 T 2 pe BI STARTER MOTOR ee pep it REMOTE CONTROL STANDARD E4 T P 2 REMOTE CONTROL DELUXE F CONTROL BLACK SINGLE PHASE GASOLINE FUELED GENSETS SPEC H ONLY DESCRIPTION OR WATERTA 611 1218 102 SEE NOTE 3 Em LOAD m 120V LOAD k l 20 W RING D AGRAM A2 m an START START 3s o CB2 90 Sx TBI ES NE N N lt X phe J4 NX 7 10 tif 12 VRe _2 REMOVE T 5 GR CB4 SEENOTE1 zb INES T xs AT Bl 47 ie
4. i EA 55 2 2 JE 87 VRI d 53 PM J4 P4 l 1 TO GENSET ve CST ENABLE SWITCH J8 P8 3 2 O P 59 4 5 e 2 HI E SEE NOTE 1 Bei tae the nce 22 H 4 7 s e iof 11 12 l P7 7 E 1 K7 1 s E2 NOTES 2 52 EA 87 1 WIS k T 1 THE ENABLE SWITCH IS CUSTOMER 1 2 P4 1 7 P1 8 PI 1 2 4 PI 3 Pls ETO GA cu WIRE 1 os Ri a J4 J3 01 7 01 8 0 41 2 JI 4 01 3 21 6 252 UL 8 2 SEE THE SECTION TITLED GENERA 9 3 GROUND STUD cr dee m B 2 TOR FOR GENERATOR RECONNEC y S m ao TIONS 821 BRI 4 OPTIONAL E 7 oes J9 LOCAL STOP z Menon 1 J 8 J8 LOCAL RETURN GND 1 1 JIO LOCAL START e 1 eh J6 i FI 2 5 Jitot HOUR zi IP al Ji20 METER 9 5 PI JI 8 4 5 45 am be ja 55 i 7 DN sj dle Aj ______ 5 5 p IB K7 RELAY EE mieh 21 A Ne VR2 VOLTAGE REGULATOR DC s r s PR VOLTAGE REGULATOR AC LOCAL te IGN COIL AIP6 3 START Y Y Yeu ei 53 IGN MODULE K5 UE J8J9 eee 51 2 U amp S oa 46 o ol 5 OPT TONAL 2 SWITCH LOW OIL PRESS I 51 1 Sitko dene o R5 POTENTIOMETER 86 B so 85 8 sio 5 RE
5. ee au tu 3 SPECIFICATIONS 5 TOLERANCES AND CLEARANCES 7 ASSEMBLY TORQUES e e YOUR Pee 9 PREPARATIONS 22 22253 10 Troubleshooting Bon e t e 10 DANY ae abe Pee ab ROE Rend 10 Special TONS sh EE CERCARE Dee ER tux ed betel xad hee us 11 Removing the Genset ae aha Ae e i Mb ue atte 11 ENGINE SUBSYSTEMS 14 Cylinder Compression i eos 14 Valve Clearance Lash Adjustment 14 Exhaust System A deut oou tx vex Racha rie du er tdg EE 15 Engine Cooling System 225222525522 17 PMG 18 19 Crankcase Breather Assembly 22 L brication System abies relier eraser mots 23 cies aus seared EC 24 Starter tad Mata 41 ENGINE CONTROL EARS US Ra 44 Control System Beginning Spec J 44 Control System Spec H 46 GENERATOR ee 49 Basic Generator Operation ot oe net Ratte e vidue os Dv tete 50 Serv
6. Fuse F1 This is a 5 amp fuse to protect printed cir cuit board A1 from overcurrent It is removable from the front of the control panel Spare fuses are inside the fuse holder Fuse F2 This is a 10 amp fuse to protect the igni tion and choke heater circuits Start Solenoid K1 The start solenoid closes the battery to the starter motor during cranking han dling up to 300 amps It includes the battery B ter minal which is readily accessible from the front for connecting the positive battery cable FUEL PUMP E2 GASOLINE FUEL SOLENOID E2 AND FILTER LPG LIQUID WITHDRAWAL FIGURE 42 TYPICAL CONTROL COMPONENTS SPEC H ONLY 46 Stop Relay K5 This relay latches the control to prevent the genset from restarting when the Start Stop switch is momentarily pushed to STOP and then released Ignition Relay K6 This relay closes to energize the ignition and choke heater circuits It is not pro vided on LPG gensets Gasoline Fuel Pump E2 The fuel pump lifts gas oline from the supply tank and delivers it under pres sure to the carburetor LPG Shutoff Solenoid FS The LPG shutoff sole noid closes against fuel supply pressure when it is de energized Battery Charging Regulator VR2 The battery charging regulator recharges the battery while the genset is running It is connected to generator termi nals B1 and B2 which provide power to the regulator at 19 21 VAC The regulator limits output
7. Inspecting the Block When rebuilding the engine thoroughly inspect the block for any condition that would make it unfit for further use This inspection must be made after all parts have been removed and the block has been thoroughly cleaned and dried 1 Make a thorough check for cracks Minute cracks may be detected by coating the sus pected area with a mixture of 25 percent kero sene and 75 percent light motor oil Wipe the part dry and immediately apply a coating of zinc oxide white lead dissolved in wood alcohol If cracks are present the white coating will be come discolored at the defective area Re move this coating after the test and before reas sembly Always replace a cracked cylinder block 2 Inspect all machined surfaces and threaded holes Carefully remove any nicks or burrs from machined surfaces Clean out tapped holes and clean up any damaged threads 78 3 Check the top of the block for flatness with a straight edge and a feeler gauge Inspecting the Cylinder Bores Inspect the cylinder bores for scuffing scratches wear and scoring If these conditions exist the cylin ders must be rebored and honed for the next over size piston If the cylinder bores look good and there are no scuff marks check the bores for wear and out of round ness as follows 1 Check cylinder bore for taper out of round ness and wear with a cylinder bore gauge tele scope gauge or inside micrometer These me
8. NN TBI SS p S N see nores j x E i 1 i 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 Oo Oe AO Or 9 0 2 55 4 8 6 7 8 9 IO II I2 I H 1 1 VRI J4 P4 1 a 1 m 1 VR2 l E N B REMOVE 1 AJJ9 75 E LKE EN 5 SWITCH 1 4 cdi i SI NOTE 11 iil B KoD BTI BI 2 N J7 M i 1 v Al 1 FI J iT 7 i au Je S aue ze a H 87A 41 104 lu 86 85 5 1115 2 6ll 1216 CR6 5 S J5 A z U6 24 87 STOP STAR 87 a 86 85 30 Tig uf HI 104 SCHEMATIC I K BTI BI HI VR2 G K6 C4 Fo a ee AC AC B f EA e 55 REMOVE Ul NE v KM e ED 2 Pi 7 X J6 1 87A K5 R3 FI J5 v Te 0 C2 PI 9PI 6 pI I2 5 10 NEST PI II Al cr5 CR VRI 7 g pcre 9 CR8 GR il KS SP K2 xv Si CR4 H HH RI R2 CR7 ra S 4 ST PI 2 P 3 PI 4 2147 J8 v XS F K2 BI 8
9. Al CR5 CRs VR a 8 Pas ER a c K3 K2 lt CR4 RI R2 2 PI 2 PI 3 PI 4 K2 A J7 J8 v 1 4 KS SEE NOTE 2 K2 E VR2 VOLTAGE REGULATOR DC T VRI VOLTAGE REGULATOR AC T IGN COIL A2 3 3 IGN MODULE 2 SWITCH LOW OIL PRESS R5 POTENTIOMETER K5 RELAY RELAY START SOLENOID ES 20V HI CHOKE GASOLINE ONLY J i GENERATOR CB2 4 Pu 240V Fi FUSE SLOW BLOW 5A E3 4 SPARK PLUGS NEUTRAL 2 FUEL PUMP OR FUEL SOL a f CR6 RECTIFIER CB4 CIRCUIT BREAKER THERMAL 2 CIRCUIT BREAKER AC OUTPUT C4 5 CAPACITOR BATTERY 12V STARTER MOTOR A3 REMOTE CONTROL STANDARD A2 REMOTE CONTROL DELUXE Al CONTROL SINGLE PHASE LPG FUELED GENSETS SPEC H ONLY DESCRIPTION OR WATERTAL 611 1210 103 WIRING DIAGRAM i LOAD LOAD LOAD GND START START Sf 5 es E usb 9 CB3 DO ac 7 gt NUN om ML
10. Drain the oil before removing the oil base Always use a new gasket when replacing the oil base An oil pump See OIL PUMP under Engine Block Assembly provides a constant flow of oil to the en gine parts and a full flow spin on filter keeps the oil clean The oil collects in the oil base where it is picked up by the oil pump pick up cup An oil by pass valve is used to control oil pressure Oil pressure should be at least 13 psi 90 kPa for Model BGD gensets and at least 20 psi 138 kPa for Model NHD gensets when the engine is at normal operating temperature If pressure drops below this value at governed speed inspect the oil system for faulty components Oil Filter And Adapter 1 Open the oil drain valve and drain the crank case oil 2 Remove the filter by turning it counterclockwise with a filter wrench 3 Loosen the two capscrews that secure the adapter to the engine block and remove the adapter and gasket The low oil pressure cutoff switch is installed in a threaded hole in the filter adapter See Figure 14 To reassemble the oil filter and adapter perform these steps in reverse order Install a new adapter gasket so that the two small oil holes are aligned with the oil holes in the block This gasket should be installed dry Coat the threads of each caps crew with non hardening sealer and torque to speci fications Oil Bypass Valve The bypass valve is located to the right and behind the gear cover Figu
11. THRUST BEARING WASHER FIGURE 89 REAR CRANKSHAFT BEARING NOTE DO NOT ADD ADDITIONAL THRUST WASHERS WHEN REPLACING THE FRONT BEARING FRONT MAIN BEARING BORE ALIGN BEARING NOTCHES WITH LOCK PINS AND MATCH OIL HOLES FRONT MAIN BEARING FIGURE 90 FRONT CRANKSHAFT BEARING Camshaft Bearings It should be noted that identical bearings are used for replacing the front and rear camshaft bearings and that they may look different from the old bear ings 1 Clean the outside of each bearing and the bear ing bore in the block and coat the outside of the bearing with Loctite brand Bearing Mount or equivalent just before pressing it into its bore 2 Press the front bearing in so that the oil hole in the bearing lines up with the oil hole in the bore Figure 91 3 Press the rear bearing in so that it is positioned 1 2 inch 12 7 mm from the outside edge of the bore There is no oil hole in the rear bore with which to line up the hole in the bearing Fig ure 92 4 Coat the bearing surfaces with engine oil after installation E BEARING WITH THE HOLE IN THE BEARING BORE FIGURE 91 FRONT CAMSHAFT BEARING OUTSIDE OF BLOCK FIGURE 92 REAR CAMSHAFT BEARING OIL SEALS Remove the rear bearing plate to replace the rear oil seal Figure 93 and the gear cover to replace the front oil seal Figure 94 Use an oil seal remover to pry out the oil seals Clean the bores of all old seal ing compound b
12. gt F J P TIT 7 pa 2 J8 a els ale z 2 E n lt H 15 2 2 6 12 12 6 K5 87 S CRE ah J5 A 46 STARI 85 Fox ee lom C4 gt ee RED pe VEA md 53 PM BLACK SCHEMATIC NOTES DISARM SWITCH BY CUSTOMER INSTALLER NO SUPPLIED BY ONAN REQUIRES CONNECTING WITH NECESSARY EXTENSION LEADS FROM JI 6 TO KEY a SWITCH AND CONNECTING FROM KEY SWITCH TO KI I AND DISCONNECTING LEAD KI I USE 16 GA Cu WIRE R2 i A fe V 2 THE COMPONENTS ON CONTROL BOARD 1 SHADED AREA ARE B CB4 SEPARATELY REPLACEABLE EXCEPT FOR FUSE F1 AND ARE SHOWN FOR Ay REFERENCE ONLY TI E REMOVE 97 3 SEE THE SECTION TITLED GENERATOR FOR GENERATOR RECONNEC SEE NOTE 1 TIONS E ws Ss PV e To 21 35 552 2 i A Je A is R3 mes 5 c2 9 P1 6 21 12 PI 5 PI 10
13. place the filter element if damaged 6 Wipe the magnet clean of the particles it has collected 7 Install a clean filter element using two new gas kets and securely tighten the center stud nut 8 Place a new O ring in the filter bowl sealing groove 9 Align the reference mark on the filter bowl with the reference mark on the filter body and torque the capscrews to 65 7 2 N m Check for and fix leaks at the filter when connections have been made to the fuel supply system The fuel filter operates at fuel supply tank pressure Fuel Vaporizer The fuel vaporizer consists of sev eral wraps of tubing around the exhaust manifold Exhaust heat vaporizes the LPG liquid The vaporiz er is not removable from the exhaust manifold Bending the fuel vaporizer tubing could weaken it to the point that it could crack allowing fuel under high pressure to escape which could result in severe personal injury or death Fuel Shutoff Solenoid Valve Test the fuel sole noid by disconnecting its long lead and jumpering it directly to the battery positive terminal on the genset Replace the solenoid if it does not click open when it is powered GASKET FILTER ELEMENT GASKET FILTER BOWL FIGURE 31 LPG FUEL FILTER LIQUID WITHDRAWAL SYSTEM 37 LPG System Vapor Withdrawal See the Installation Manual for important recom mendations regarding the installation of an LPG va por withdrawal type of fuel
14. 3c 2 11 T8 pB3 T5 g LINE TO LINE E i BLACK CB1 LOAD BLK YEL CB2 LOAD Ti T6 GREEN GND T12 GENERATOR CONTROL BOX LINE TO NEUTRAL T9 27 mpm ee WHITE NEUTRAL USE A DOUBLE END MALE 1 4 INCH FASTON CONNECTOR TO CONNECT THE GENERATOR LEADS REMOVE AND DISCARD BOTH LEADS CONNECTED TO LEAVE CB3 IN PLACE TO KEEP THE OPENING COVERED FIGURE 61 THREE PHASE 12 LEAD GENERATOR RECONNECTIONS 61 Engine Block Assembly Performing major service on the engine block as sembly requires that the genset be removed from the vehicle See Preparations The control genera tor and all engine subsystems must also be re moved for complete access to the block assembly Refer to the previous sections for disassembly and removal procedures CYLINDER HEADS See Figures 62 and 63 Remove and clean the cylin der heads as follows when poor engine perfor mance is noticed 1 Remove the cylinder head bolts by using a 1 2 inch socket wrench Lift off the cylinder head The heads may warp if they are removed while hot Wait until the engine has cooled before removing the heads 2 After remov
15. 44 Starter Solenoid K6 The starter solenoid is part of the starter motor assembly It engages the starter pinion and connects the starter motor to the battery for cranking Hour Meter The hour meter is mounted as an inte gral part of the control panel It is not resettable Ignition Coil T1 The ignition coil provides spark for igniting the fuel Gasoline Fuel Pump E2 The fuel pump lifts gas oline from the supply tank and delivers it under pres sure to the carburetor A fuel shutoff solenoid may also have been connected in parallel to the fuel pump by the customer to prevent fuel spillage in the event the vehicle rolls over LPG Shutoff Solenoid FS The LPG shutoff sole noid closes against fuel supply pressure when it is de energized Choke Heater H1 The choke heater opens the choke to the full open run position gasoline gen sets only Low Oil Pressure Cutout Switch S2 This switch opens in the event engine lubricating oil pressure drops below 5 psi 34 kPa to de energize the run relay and shutdown the genset PMG The PMG provides power for recharging the cranking battery through VR2 during operation of the genset and a signal for the control board A1 for start disconnect See Engine Subsystems for de tails Battery Charging Regulator VR2 The battery charging regulator recharges the battery while the genset is running It is connected to the PMG The regulator limits output to 14 2 volts and 10
16. Control Components The control system consists of the following compo nents Control Panel See Figure 41 The Start Stop Re set switch hour meter and indicator lights are mounted on the control panel Control board A1 and start relay K5 are mounted on the back of the control panel Only start relay K5 is separable from the con trol panel assembly for replacement Start Stop Reset Switch S1 This is a momen tary contact type switch mounted as an integral part of the control panel Fuse F1 This is a 10 amp mini bayonet type fuse mounted on the side of the control box to protect printed circuit board A1 from overcurrent Start Relay K5 The starter solenoid K6 is ener gized by the control board A1 through this relay It is mounted in a socket on the back of the control panel Gen AC Fuel Pump Ignition AVR Field Start Sol Low Bat STOP RESET START SWITCH Stop Reset Cranking Gen AC LED green will be OFF Fuel Pump LED green will be ON Ignition LED green will be ON AVR Field LED green will be Start Sol LED green will be Low Bat LED red MAY flash ON Genset started and running Gen AC LED green will be ON Fuel Pump LED green will be Ignition LED green will be ON AVR Field LED green will be OFF Start Sol LED green will be OFF Low Bat LED red will be OFF FIGURE 41 CONTROL PANEL BEGINNING SPEC J
17. FLOOR FIGURE 3 TYPICAL FLOOR MOUNTED GENSET 13 Engine Subsystems These engine subsystems or service procedures do not require removal of the cylinder heads gearcase or main bearings for access and may be serviceable without removing the genset from the vehicle CYLINDER COMPRESSION TEST Examining the spark plugs and testing cylinder compression can tell much about the condition of the valves piston rings and cylinders Test cylinder compression as follows 1 Start the genset and let it warm up 2 Stop the genset and remove and inspect the spark plugs See IGNITION SYSTEM in this section Insert the compression gauge nozzle into one of the spark plug holes hold the throttle open and crank the engine Note the pressure indi cated by the gauge Repeat the test on the other cylinder Refer to Engine Block Assembly if cylinder compression test pressures do not meet Speci fications VALVE CLEARANCE LASH ADJUSTMENT See Figure 4 The engine is equipped with adjust able valve tappets Adjust the valve clearance only when the engine is at ambient temperature 1 Remove all parts that block access to the valve tappets 2 Remove the spark plugs to make turning the engine easier 3 Place a socket wrench on the flywheel caps 14 crew and rotate the crankshaft in a clockwise direction until the left intake valve viewed from flywheel end opens and closes Continue turn ing the cran
18. GENSETS DETAIL LPG LIQUID WITHDRAWAL GENSETS FIGURE 17 GOVERNOR ROD 26 Note The following groups of adjustments must be performed in sequence They apply to gensets BE GINNING SPEC L For gensets PRIOR TO SPEC L see Page 29 Idle Speed Stop Adjustment The frequency specifications for 60 Hz gensets are followed in pa rentheses by the specifications for 50 Hz gensets 1 Start the genset and let it warm up for ten min utes under 1 2 to 3 4 rated load On vapor with drawal type LPG gensets it might be necessary to first adjust the supply pressure as instructed under LPG System Components to get the gen set to start 2 Disconnect the load check for zero amps Pull the governor rod so that the tang on the throttle lever bears against the idle speed stop screw Adjust the screw to obtain 54 56 Hz 44 46 Hz On LPG carburetors the stop screw has a lock nut Frequency Adjustments The frequency specifi cations for 60 Hz gensets are followed in paren theses by the specifications for 50 Hz gensets 1 Set the altitude adjust knob gasoline only on the carburetor to your altitude 2 Disconnect all loads check for zero amps Then check no load frequency If necessary turn the governor speed adjusting screw to ob tain a no load frequency of 62 63 Hz 51 5 52 5 Hz 3 Check output voltage See Generator if output voltage cannot be adjusted to within 10 percent of rated voltage Table 3 4 See Trou
19. M ne xdi 2 GOVERNOR ACTUATOR i i E4 CBI 2 CIRCUIT BREAKER AC OUTPUT e I 5 CAPACITOR E BATTERY 12 STARTER MOTOR REMOTE CONTROL STANDARD A4 ELECTRONIC GOVERNOR iS Al CONTROL ASSY te SINGLE PHASE 50 HERTZ GENSETS BEGINNING SPEC J Wu sesion 611 1234 100 WIRING SEE SECTION TITLED GENERATOR FOR GENERATOR CONNECTIONS LOAD LOAD CB2 T2 CBI BLK 3l RED RED WHT BLK WHT ENABLE SWITCH ono ole T BT 27 F 2 P7 gt P5 45 5 7 s am 22 E n ga els 6 A a IT es 85 ee J ES ra H m LZ ee RED 4
20. Only 104 This is the service manual for the Series BGD and NHD generator sets gensets for commercial ve hicles Read and carefully observe all of the instruc tions and precautions in this manual Figure 2 illus trates a typical genset Improper service or parts replace ment can lead to severe personal injury or death and to damage to equipment and property Ser vice personnel must be qualified to perform electrical and mechanical service Unauthorized modifications or re placement of fuel exhaust air intake or speed control system components that affect engine emissions are prohibited by law in the State of California LPG liquified petroleum gas is flammable and explosive and can cause as phyxiation NFPA 58 Section 1 6 requires all persons handling LPG to be trained in proper handling and operating procedures See the Operator s Manual for instructions concern ing operation maintenance and storage and for rec ommendations concerning engine lubricating oil and fuel See the Installation Manual for important recom mendations concerning the installation and for a list of the installation codes and standards for safety which may be applicable See the Parts Manual for parts identification num bers and required quantities and for exploded views of the genset subassemblies Genuine Onan re placement parts are recommended for best results When contacting Onan for part
21. Piston Installation 1 The crankshaft must be in place and should have been serviced already if crankshaft ser vice was required See CRANKSHAFT 2 Turn the crankshaft to position the Number 1 rod bearing journal side opposite oil filter side at the bottom of its stroke 3 Lubricate the Number 1 piston assembly and cylinder with engine oil Compress the rings with a ring compressor as shown in Figure 85 Install the bearing insert in the piston rod 4 Position the piston and rod assembly in the inder block with the connecting rod oil hole up Figure 84 PISTON RING IN CYLINDER BORE FEELER GAGE FIGURE 84 CONNECTING ROD OIL HOLE 73 5 Tap the piston into the bore with the handle end of the hammer until the connecting rod is seated on the crankshaft journal Figure 85 If the crankshaft has been reground and or new rods are being installed check the bearing clearance with Plasti gage as instructed below under Rod Bearing Clearance Install the rod bearing cap as follows A Lubricate the cap bolts with engine oil and torque to 5 Ibs ft 7 N m B Strike the cap rod joint using a hardwood block and a leather or plastic mallet to re move any misalignment Figure 86 C Torque the cap bolts to 14 Ibs ft 19 N m Recheck the torque on each bolt after both bolts have been torqued Failure to align the rod and cap can result in high engine oil temperature and failure of the rod Ins
22. 125 AND INSULATED FEMALE 1 4 INCH FASTON CONNECTOR REMOVE AND DISCARD BOTH LEADS CONNECTED TO CB1 LEAVE CB1 IN PLACE TO KEEP THE OPENING COVERED FIGURE 59 SINGLE PHASE 4 LEAD 60 Hz GENERATOR RECONNECTIONS 59 3 WIRE 50 HZ 110 120 220 240 VAC 110 120 TNI 220 240 VAC WHITE NEUTRAL BLACK CB2 LOAD GREEN GND BLACK CB1 LOAD TROL BOX 2 WIRE 50 HZ 110 120 VAC L1 ORAS L3 110 120 VAC BLACK CB1 LOAD BLACK CB2 LOAD WHIT WHITE NEUTRAL GREEN GND CONTROL BOX 2 WIRE 50HZ 220 240 VAC T1 E CB1 T3 CB2 m 220 240 VAC BLACK CB2 LOAD WHITE NEUTRAL EN GREEN GND CONTROL BOX INSTALLER MUST PROVIDE A NO 12 AWG TYPE XLPE CONDUCTOR 125 C AND INSULATED FEMALE 1 4 INCH
23. 50 BRUSH BLOCK ASSEMBLY 53 Re installing the Rotor in the Generator It is recommended that the rotor be re installed in the generator first and then that the entire generator be mounted on the genset as instructed under Re mounting the Generator on the genset Re installation of the rotor is the reverse of removal Note the following 1 Replace the slip ring assembly rotor bearing and stator if necessary 2 Make sure the brush block assembly has been removed or that the wire is holding both brushes up and out of the way 3 Make sure the rubber O ring is in place in the bearing bore and then carefully lower the rotor into the generator The rotor bearing should fit snugly into the bearing bore 4 Install the brush block assembly if it was re moved If it was left in place pull the brush pig tails and remove the retaining wire If neces sary loosen the brush block mounting screws align the brush block so that the brushes are centered on the slip rings and retighten the mounting screws 5 Connect the lead marked F1 to the outboard brush terminal and the lead marked F2 to the in board brush terminal and snap the cover on Removing the Stator from the Generator See Figure 51 To remove the stator from the gener ator housing 1 Upend the generator as shown 54 2 Remove the rotor as instructed under Remov ing the Rotor from the Generator 3 Disconnect all the stator leads and pull them from the co
24. 51 5 52 5 Hz no load frequen cy Check droop again and repeat the ad justments if necessary 28 B If droop from no load frequency is less than 2 Hz 2 Hz for Model BGD or 3 Hz 2 Hz for Model NHD turn the governor sensitivity adjusting screw Figure 17 one turn clockwise Disconnect the load and if necessary readjust the governor speed adjusting screw to return to 62 63 Hz 51 5 52 5 Hz no load frequency Check droop again and repeat the adjustments if necessary 3 Check governor response under 1 4 1 2 and 3 4 rated loads See Troubleshooting if hunting is unacceptable Carburetor Replacement Beginning Spec L Other than turning the altitude adjust knob shown in Figure 18 which changes the main fuel mixture within a limited range gasoline carburetors only fuel mixture adjustments should not be attempted on gasoline or LPG carburetors Nor should the car buretor be overhauled Instead a malfunctioning carburetor should be replaced Before replacing a carburetor however make certain 1 that all other necessary engine and generator adjustments and repairs have been performed and 2 that the carbu retor is actually malfunctioning by carefully follow ing the troubleshooting procedures in Troubleshoot ing LPG carburetors are usually not the cause of prob lems Make certain all other possible causes of the problem have been eliminated before replacing an LPG carburetor Unauthorized modifications
25. CYLINDER COMPRESSION TEST in Engine Subsys functioning mechanically tems and service as necessary according to Engine Block As sembly 93 THE GENSET RUNS BUT THERE IS NO OUTPUT VOLTAGE There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The line circuit breakers are Find out why the circuit breakers were turned OFF make sure it OFF or have TRIPPED is safe to reconnect power and then throw the circuit breaker ON Beginning Spec J the Gen If the circuit breakers have tripped shut down the genset and ser AC indicator light will be on vice as necessary to clear the short circuit or ground fault that if generator output volt caused tripping and then RESET the circuit breakers and restart age ahead of the circuit the genset breakers is normal 2 A line circuit breaker is Shut down the genset make sure the power output lines from the faulty genset have been disconnected from all other sources of power attempt to RESET the circuit breaker and throw it ON and check for electrical continuity across its terminals Replace the circuit breaker if there is measurable resistance 3 The generator is connected Remove
26. Cranking voltage is too low Clean and tighten or replace the battery cable connectors and to crank the engine cables at the battery and the genset See the Installation Manual to verify that the battery cable sizes are adequate b Recharge or replace the battery Specific gravity for a fully charged battery is approximately 1 260 at 80 F 27 C c If the genset is in standby service install a battery charger d Once the genset has been started troubleshoot the battery charging circuit according to THE GENERATOR DOES NOT CHARGE THE BATTERY Beginning Spec J if the Low Bat indi cator stays on during operation recheck all of the above steps Beginning Spec J 7 The starter motor assem Check and tighten connections at starter solenoid terminals S bly is malfunctioning or not and M and push and hold in the Start switch connected properly If the Start Sol indicator does not light go to Step 8 If the Start Sol indicator on the control panel lights measure voltage at solenoid terminal M If there is at least 9 VDC but the motor does not function properly service or replace the motor assembly If there is not at least 9 VDC replace the solenoid See ELECTRIC STARTER in Engine Subsystems 8 Control A1 or start relay K5 Remove the control panel and check for B at relay K5 terminal are faulty or not properly 30 K5 is mounted in a socket on the back of the panel connected If there is no voltage reconnect wirin
27. HERE FIGURE 81 MEASURING PISTON DIAMETER Piston Ring Gap Before installing new rings on the piston check the ring gap by placing each ring squarely in its cylinder at a position corresponding to the bottom of its travel Figure 82 The gap should be 0 010 0 020 inch 0 25 0 50 mm Do not file the ring ends to increase the end gap If the ring end gap does not meet the specifications check the correctness of ring and bore sizes A cyl inder bore that is 0 001 inch 0 03 mm undersize will reduce the end gap 0 003 0 08 m Rings that are 0 010 0 020 0 030 and 0 040 inch 0 25 0 51 0 76 and 1 02 mm oversize should be used on corresponding oversize pistons Piston Assembly 1 Lubricate all parts with clean engine oil 2 Line up the piston and connecting rod and in sert the piston pin The piston pin is a full float ing type kept in place by a lock ring on each side Push the lock rings in by thumb pressure or pry them in with a small screwdriver Make sure they are properly seated Wear safety glasses and hold your thumb over the lock ring to keep it from flying out and getting lost or causing per sonal injury 3 Refer to Figure 83 Use a piston ring spreader to install the piston rings to prevent twisting or excessive expansion Follow the instructions in the ring kit exactly Note which ring goes in which groove and which side of the ring is up Also note that the oil control ring is an assem bly
28. Remove the control panel and separate control board 1 from it by removing the four mounting screws 3 With an ohmmeter check for good electrical contact between each pin and jack of connector P1 J1 To test a connection touch one meter probe to the back of the pin which is bare Dis connect the fast on connector on the other end of the lead connected to the J1 jack and touch the other meter probe to the connector Reconnect the lead before checking the next connection to minimize the possibility of mak ing wrong reconnections Replace the connector jack lead assembly if the jacks are corroded or there is measurable resistance greater than zero ohms at any con nection 4 Reconnect the battery and try to start and run the genset FUSE 1 CONNECTOR P1 J1 FOR BATTERY GENERATOR AND CONTROL CONNECTIONS 5 If the engine does not crank disconnect the fast on connector on the end of the connector Pl J1 lead marked K1 S J1 9 Measure volt age between the connector on the end of the lead and a good engine ground while pressing the panel start switch If the voltmeter indicates zero volts check fuse F1 on the control board If it is good replace control board 1 If the volt meter indicates at least 9 volts the problem is not in the control board Go to Troubleshooting If the engine cranks but does not start discon nect the fast on connectors on the ends of the connector P1 J1 leads marked J6 J1 6 and E
29. Start Stop switch to Start and measure voltage at the functioning starter motor terminal If there is at least 9 VDC but the motor does not function replace the starter motor See ELECTRIC STARTER in Engine Subsystems 83 THE ENGINE CRANKS BUT DOES NOT START There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 Fuse F2 on the side of the Check for and repair ground faults in the choke heater H1 and control box has blown ignition coil T1 circuits See Wiring Diagrams Replace the fuse Spec H Gasoline only with a 10 amp slow blow mini bayonet type 2 The fuel supply shutoff Service as necessary valve is closed or the fuel tank is empty 3 Cranking voltage is too low Clean and tighten or replace the battery cable connectors and to reach require cranking cables at the battery and the genset See Installation Manual to speed verify that the battery cable sizes are adequate Recharge or replace the battery Specific gravity for a fully charged battery is approximately 1 260 at 80 F 27 C If the genset is in standby service install a battery charger Once the genset has started troubleshoot
30. and clean the regulator assembly if it does not pass either test Replace the regu lator if it still does not pass either test Most parts cleaning solvents are flammable and corrosive and can cause severe burns and inflammation Use only as recommended by the manufacturer 36 SECONDARY DIAPHRAGM PRIMARY PRIMARY GASKET PRIMARY DIAPHRAGM FIGURE 29 DEMAND REGULATOR ASSEMBLY CONNECT THE INLET TOA SOURCE OF COMPRESSED AIR THE GAUGE SHOULD INDICATE APPROXIMATELY 1 5 PSI 10 3 KPA AND HOLD STEADY FIGURE 30 TESTING THE DEMAND REGULATOR LIQUID WITHDRAWAL SYSTEM Fuel Filter See Figure 31 The fuel filter removes rust and scale and other solid particles from the LPG liquid to keep them from embedding in the valve seats of the shutoff valve and pressure regulator and causing them to leak A magnet traps iron and rust particles and a filter element traps non magnet ic particles Disassembling and Cleaning the Fuel Filter 1 Purge the LPG system as instructed on Page 12 before beginning disassembly 2 Remove the four capscrews and lock washers that hold the filter bowl to the filter body 3 Separate the filter bowl from the filter body and discard the O ring seal 4 Remove the nut and washer from the center stud and pull out the filter element 5 Wash the filter element in kerosene to remove the particles it has collected Blow it dry with low pressure 30 psi 207 kPa compressed air Re
31. in the Start switch and immediately pull off the wire connector at starter solenoid termi nal S to disengage the starter Replace the flywheel assembly Figure 9 if the output is less than 29 VAC 87 THE ENGINE STOPS WHEN THE START SWITCH IS RELEASED SPEC H ONLY There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action In normal operation run relay K3 on control board A1 must remain powered in order to keep the genset running when the start switch is released See Wiring Diagrams Three things must occur to keep run relay K3 powered 1 engine oil pressure must be sufficient to close low oil pressure cutout switch S2 2 stop relay K5 must open and 3 output from generator winding B1 B2 must be sufficient to pull in start disconnect relay K2 on control board 1 To isolate the problem plug a test lamp or voltmeter into a convenient power receptacle on the vehicle Start the genset and keep it running by holding in the Start switch and go to NORMAL OUT PUT VOLTAGE or NO LOW OUTPUT VOLTAGE as appropriate Normal Output Voltage 1 The engine oil level is low Check engine oil level and fill as necessary 2 The engine
32. misfires test the ignition system as fol lows to quickly determine if the problem is in the igni tion system First recheck clean and tighten the connections at the ignition coil terminals See Wir ing Diagrams for the proper connections at the and terminals Gasoline and LPG are flammable and explosive and can cause severe personal injury or death Park the vehicle in a well venti lated area leave the generator compartment door open for several minutes and make sure you cannot smell gas or gasoline vapors before conducting this test Have an ABC rated fire ex tinguisher handy 1 Park the vehicle in a well ventilated area leave the generator compartment door open for sev eral minutes and make sure you cannot smell gas or gasoline vapors before conducting this test 2 Remove one of the spark plugs 3 Reconnect the spark plug cable and lay the spark plug on bare engine metal to ground it HIGH VOLTAGE To prevent electric shock do not touch the spark plug or wire during this test 4 Crank the engine and observe the spark A strong consistent spark indicates that the igni tion system is probably functioning properly and that the problem is elsewhere See Trou bleshooting Service the ignition system as re quired if the spark is weak or inconsistent Spark Plug Cable Resistance Tests Remove both spark plug cables and check resist ance across the ends with an ohmmeter Replace a cable if resistance
33. or re placement of fuel exhaust air intake or speed control system components that affect engine emissions are prohibited by law in the State of California See the instructions on how to remove and replace the carburetor under the subheadings AIR CLEAN ER ASSEMBLY and CARBURETOR AND INTAKE MANIFOLD ASSEMBLY in this section Note The following groups of adjustments must be performed in sequence They apply to gensets PRIOR TO SPEC L only For gensets BEGINNING SPEC L see Page 27 Idle Speed Stop Adjustment The frequency specifications for 60 Hz gensets are followed in pa rentheses by the specifications for 50 Hz gensets 1 If the carburetor has been overhauled gently turn the idle and main fuel mixture screws in by hand until they seat For Gasoline Gensets Turn the idle mixture screw out 1 turn and the main fuel mixture screw out 1 1 4 turns so that the engine will start and run For LPG Gensets Turn the idle mixture screw out 1 1 4 turns and the main fuel mixture screw out 2 1 2 turns so that the engine will start and run Forcing a mixture adjusting screw in tight will score the needle and seat Turn it lightly by hand only 2 Start the genset and let it warm up for ten min utes under 1 2 to 3 4 rated load On vapor with drawal type LPG gensets it might be necessary to first adjust the demand regulator and supply pressure as instructed under LPG System Components to get the genset to start 3 Disconne
34. per formance See VALVE CLEARANCE LASH ADJUSTMENT under Engine Subsystems for instructions on how to adjust valve clearance VALVE CLEARANCE VALVE ADJUSTING NUT TAPPET VALVE SPRING RETAINER VALVE CAP FIGURE 64 MODEL BGD VALVE SYSTEM VALVE SEAT VALVE SPRING VALVE SPRING VALVE CLEARANCE VALVE ADJUSTING INSERT RETAINER NUT CAMSHAFT TAPPET EXHAUST VALVE ROTATOR RUBBER VALVE STEM RETAINER GASKET SEAL OPTIONAL LOCK FIGURE 65 MODEL NHD VALVE SYSTEM 63 Inspecting the Valve System The valve system is accessible by removing the inder heads and the valve covers on top of the en gine Use a valve spring compressor Figure 66 to remove and replace the valves from the cylinder block Make sure to first plug the breather hole in the Number 1 cylinder valve box opposite oil filter side to prevent the valve keepers from falling into the crankcase Valve Face Check the valve face for evidence of burning warping out of roundness and carbon de posits Figure 67 Burning and pitting are caused by the valve failing to seat tightly This condition is often caused by hard carbon particles on the seat It may also be caused by weak valve springs insufficient tappet clear ance valve warpage and misalignment Warping occurs chiefly in the upper stem because it is exposed to intense heat Out of roundness re sults from warping when the seat is pounded by a valve whose head is not in line with
35. phragm to simulate carburetor venturi vacuum 1 Continue with the test setup for adjusting LPG supply pressure shown in Figure 33 If the regu lator is being tested on the bench connect it to a source of air pressure regulated to 11 inches 280 mm WC If this is a bench test of the regu lator make sure the diaphragm is in a verti cal plane see Figure 32 otherwise the weight of the diaphragm will cause erro neous readings of lock off pressure 2 in two hoses to the end of the hose con nected to the regulator vent fitting 3 8 inch 1 D Use one hose to provide the test pres sure and the other to measure pressure by con necting it to an inclined manometer calibrated with 0 01 inch or 0 1 mm divisions and having a range of at least 1 inch 25 mm 3 Disconnect the hose to the carburetor and at tach a soap bubble to the regulator outlet hose fitting While reading the pressure indicated by the inclined manometer and watching the soap bubble blow lightly into the hose being used to pressurize the regulator Regulator lock off pressure is the minimum pressure that will cause gas to flow through the regulator as indi cated by the expanding soap bubble At first the soap bubble may expand due to diaphragm movement but will stop expanding if gas or air is not flowing through the regulator For Gensets Beginning Spec L Replace the demand regulator if the lock off pressure does not fall between 0 15 and 0 25 inc
36. small amount of grease to help hold the cup in position The rounded side of the gover nor yoke must ride against the governor cup Turn the governor arm and shaft clockwise as far as possible and hold it in this position until the gear cover is installed flush against the crankcase Be careful not to damage the gear cover oil seal TOP OF ROLL PIN 3 4 IN 19 0 mm ROTATE THE GOVERNOR CUP SO THAT THE ROLL PIN FITS INTO THE HOLE WITH THE GROMMET FIGURE 72 GEAR COVER ASSEMBLY 67 GOVERNOR CUP Removal 1 2 3 Remove the gear cover See GEAR COVER Remove the snap ring from the camshaft cen ter pin Figure 73 Slide the governor cup off making certain to catch the flyballs Replace any flyball that is grooved or has a flat spot Examine the ball spacer If the arms of the ball spacer are worn or otherwise damaged re move the spacer by splitting it with a chisel Use a press to install a new spacer on the camshaft gear The governor cup must spin freely on the cam shaft center pin without excessive looseness or wobble If the race surface of the cup is grooved or rough replace it with a new one Installation The governor cup and flyballs are easily installed when the camshaft assembly is removed from the engine If necessary the engine may be tilted up to install the cup and flyballs ii 2 Put the flyballs between the spacer arms and install the cup on the cente
37. the control panel and verify that all generator connec wrong tions are according to the appropriate connection diagram in Generator 4 A main stator winding is Test and service according to TESTING THE GENERATOR in open Beginning Spec J if Generator the Gen AC indicator light is not on there is a problem in the generator or voltage regulator 5 The quadrature winding of Test and service according to TESTING THE GENERATOR in the stator is open single Generator phase gensets only 6 Voltage regulator VR1 is Test and service according to TESTING THE VOLTAGE REG faulty ULATOR in Generator 94 THE OUTPUT VOLTAGE IS TOO HIGH OR TOO LOW There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 Voltage has been adjusted Adjust the voltage as required For single phase gensets the ad incorrectly justing rheostat is on the control panel inside the control box on Spec J and for three phase gensets on the voltage regulator 2 Frequency has been ad Adjust according to Governor and Carburetor Adjustments under justed incorrectly FUEL SYSTEM in Engine Subsystems 3 The brushes are not making Service as nece
38. to 10 amps Low Oil Pressure Cutout Switch S2 This switch opens in the event engine lubricating oil pressure drops below 5 psi 34 kPa to de energize the run relay and shutdown the genset Battery Charging Circuit Breaker CB4 This isa thermal type automatic reset circuit breaker to pro tect the charging circuit On 1 phase gensets it is lo cated inside the control box and is tied to the leads from battery charging regulator VR2 On 3 phase gensets it is mounted on the bracket for output volt age regulator VR1 Remote Control A2 A3 Optional The remote control is an optional accessory that enables the genset to be operated from a remote location The deluxe control includes a running time meter and battery condition meter Sequence Of Operation See Wiring Diagrams for the appropriate wiring schematic while working through the following de scription 1 Holding Start Stop switch S1 at Start causes relay K4 on control board 1 to pull in causing the following components to be energized by the battery Start Solenoid K1 The engine should crank Fuel Pump 1 or Fuel Solenoid FS The electric fuel pump should start pumping gaso line or the LPG fuel solenoid should open Relay K5 Relay K5 opens to energize run relay K3 Relay K6 Relay K6 closes to energize the ignition 1 and choke heater H1 circuits The engine should start Generator Field Battery current energizes the generator field th
39. 2 R4 FI i Ok a2 7 SEE NOTE 3 hale pia 2 6 pe s Jeep Jeep EE 19 Ol ry LI H A2 C NSC NEA SS BCM AS HE yt ii P4 VRI z THREE PHASE GENSETS SPEC H ONLY NOT SEE NOTE 2 ES DISARM SWITCH BY CUSTOMER INSTALLER SUPPLIED BY ONAN REQUIRES CONNECTING WITH NECESSARY EXTENSION LEADS FROM JI 6 TO KEY SWITCH AND CONNECTING FROM KEY SWITCH TO KI I AND DISCONNECTING LEAD AT KI I USE 16 GA Cu WIRE THE COMPONENTS ON CONTROL BOARD A1 SHADED AREA ARE NOT SEPARATELY REPLACEABLE EXCEPT FOR FUSE F1 AND ARE SHOWN FOR REFERENCE ONLY SEE THE SECTION TITLED GENERATOR FOR GENERATOR RECON NECTIONS K6 RELAY IGN VR2 VOLTAGE REGULATOR DC VRI VOLTAGE REGULATOR AC TI IGN COIL 53 IGN MODULE S2 SWITCH LOW OIL PRESSURE F2 FUSE K5 RELAY KI RELAY START SOLENOID HI CHOKE GASOLINE ONLY GI GENERATOR FI FUSE SLOW BLOW 5A E3 4 SPARK PLUGS 2 FUEL PUMP OR FUEL SOLENOID CR6 RECTIFIER CIRCUIT BREAKER THERMAL 01 23 CIRCUIT BREAKER AC OUTPUT C4 5 CAPACITOR BTI BATTERY 12V STARTER MOTER REMOTE CONTROL STANDARD A
40. 2 REMOTE CONTROL DELUXE Al CONTROL ASSY ITEM DESCRIPTION 611 1224 Onon Cummins Power Generation 1400 73rd Avenue N E Minneapolis MN 55432 763 574 5000 Fax 763 528 7229 Cummins and Onan are registered trademarks of Cummins Inc
41. 2 J1 12 Measure voltage between the con nector on the end of each lead and a good en gine ground while pressing the panel start switch Replace control board A1 if the voltme ter indicates zero volts at either connector If the voltmeter indicates at least 9 volts at both con nectors the problem is not in the control board Go to Troubleshooting If the engine starts but stops when the panel start switch is released the problem could be low oil pressure a faulty low oil pressure cutoff switch or no generator output voltage Go to Troubleshooting Replace control board 1 if oil pressure switch and generator are normal CONNECTOR P2 J2 FOR REMOTE CONTROL CONNECTIONS START STOP SWITCH S1 FIGURE 43 CONTROL BOARD 1 SPEC ONLY 48 Generator These are 4 pole revolving field generators with slip rings and electronic voltage regulators Single phase generators have quadrature windings and three phase generators main winding taps for field excitation Spec generators have auxiliary wind ings for battery charging The generator rotor and THREE PHASE VOLTAGE REGULATOR WITH VOLTAGE ADJUSTING POTENTIOMETER A STEP DOWN VOLTAGE REFERENCE TRANSFORMER IS MOUNTED ON THE DRIP PAN BEGINNING SPEC J STATOR CLAMP ROTOR END BEARING COOLING BLOWER WHEEL AND STARTER RING GEAR ENGINE TO GENERATOR ADAPTER HOUSING engine crankshaft have a tapered coupling secured by the rotor through b
42. C OUTPUT 4 5 CAPACITOR BATTERY I2V BI STARTER MOTOR REMOTE CONTROL STANDARD A4 ELECTRONIC GOVERNOR CONTROL ASSY ITEM DESCRIPTION OR MATERIAL 611 1232 101 SEE NOTE 3 WIRING DIAGRAM SCHEMATIC NOTES 2 t LOAD cee o i ci GDE DISARM SWITCH BY CUSTOMER INSTALLER NO 20 a EM HI A SUPPLIED BY ONAN REQUIRES CONNECTING WITH B NECESSARY EXTENSION LEADS FROM JI 6 TO KEY x SW
43. Caution This document contains mixed page sizes 8 5 x 11 or 11 x 17 which may affect printing Please adjust your printer settings according to the size of each page you wish to print Service Manual Onon Model BGD and NHD Generator Sets Beginning Spec H YX SC B D Printed in U S A 11 95 965 0500 Safety Precautions Thoroughly read the OPERATOR S MANUAL before operating the genset Safe operation and top perfor mance can be obtained only with proper operation and maintenance The following symbols in this Manual alert you to poten tial hazards to the operator service person and equip ment Alerts you to an immediate hazard which will result in severe personal injury or death AWARNING Alerts you to a hazard or unsafe prac tice which can result in severe personal injury or death CAUTION Alerts you to a hazard or unsafe prac tice which can result in personal injury or equipment damage Electricity fuel exhaust moving parts and batteries present hazards which can result in severe personal inju ry or death GENERAL PRECAUTIONS Keep ABC fire extinguishers handy Make sure all fasteners are secure and torqued properly Keep the genset and its compartment clean Ex cess oil and oily rags can catch fire Dirt and gear stowed in the compartment can restrict cooling air Be
44. FASTON CONNECTOR REMOVE AND DISCARD BOTH LEADS CONNECTED TO CB1 LEAVE CB1 IN PLACE TO KEEP THE OPENING COVERED REMOVE JUMPER W2 FOR ISOLATED NEUTRAL FIGURE 60 SINGLE PHASE 4 LEAD 50 Hz GENERATOR RECONNECTIONS 60 3 PHASE 4 WIRE WYE 60HZ 120 139 208 240 VAC AND 50 HZ 110 127 190 220 VAC E LINE TO LINE BLACK CB1 LOAD BLK YEL CB2 LOAD i WHITE NEUTRAL GREEN GND T12 BLACK CB3 LOAD GENERATOR CONTROL BOX LINE TO NEUTRAL BIR LINE TO LINE ri BLACK CB1 LOAD BLK YEL CB2 LOAD Y_ BLACK CB3 LOAD WHITE NEUTRAL GREEN GND LINE TO NEUTRAL YYYN YYYIY YYYY T12 25 GENERATOR _ CONTROL I BOX 1 PHASE 3 3 WIRE DOUBLE DELTA 60 HZ 120 240 VAC AND 50 HZ 110 120 220 240 VAC ET 7 amp 4 m T10 0
45. INTAKE MANIFOLD Lk MANIFOLD w MANIFOLD GASKET 2 Se E m GASOLINE CARBURETOR CHOKE ASSEMBLY DETAIL OF GOVERNOR ROD THROTTLE LEVER CONNECTION gasoline 8 GASOLINE FUEL INLET The fuel line from a remote or mounted pump is connected here through an elbow fitting FIGURE 16 TYPICAL FUEL SYSTEM 25 Governor and Carburetor Adjustments Careful adjustments of the carburetor and governor are essential for top performance Perform all nec essary engine and generator maintenance and re pairs before making these adjustments These adjustments require the use of meters to measure voltage frequency and amperage and a stepped load bank of at least 8 kW where a portion of at least 600 watts is variable Digital meters are recommended Accuracy should be at least 0 3 per cent for frequency measurement and 0 5 percent for voltage measurement It is recommended that the genset be disconnected from the AC service panel of the vehicle If the gen set is not disconnected disconnect or unplug all voltage and frequency sensitive devices throughout the vehicle to protect them from the variations in fre quency and voltage that occur during these adjust ments Disconnect or unplug all voltage and frequency sensitive devices such as TVs VCRs computers and other solid state elec tronic devices before making governor and car buretor adjustments Typically some internal circuits are powered when these types o
46. ITCH AND CONNECTING FROM KEY SWITCH TO KI I m 0 I Fo AND DISCONNECTING LEAD AT KI I USE l6 GA Cu WIRE X E oe oe is De Jd XR 2 THE COMPONENTS ON CONTROL BOARD A1 SHADED AREA ARE NOT CORE Nri Be CB4 a SEPARATELY REPLACEABLE EXCEPT FOR FUSE F1 AND ARE SHOWN FOR TBI NI ee REFERENCE ONLY 53 ER 3 SEE THE SECTION TITLED GENERATOR FOR GENERATOR RECONNEC pos R5 N SEE NOTE 1 TIONS Le LS 3 REMOVE P LO KI h l 2 z a O Ne NV D VRI J4 poc HES sn 2 gt Pic s2 pe a A J6 4 K5 5 o Al CRB CR24 VRI gt 7 CREE 589 ECR3 1 CRI K3 a 2 K2 Si CR4 HHH RI R2 KI REMOVE CRY e AC B AC 2 MA ST 1 Pie Pia PIs F Nu J7 J8 CB4 SEENOTE1 is SEE NOTE 2 E Ll MOT W e us aT J7 1 FI l JI P VR2 VOLTAGE REGULATOR DC T 2 VRI VOLTAGE REGULATOR AC 48 SE 2 IGN COIL INT Al S3 IGN MODULE 5 sli 5 5 2 SWITCH LOW OIL PRESS PG R5 POTENTIOMETER m E 5 6 RELAY SI n RELAY START SOLENOID E sl 18 ed HI CHOKE GASOLINE ONLY o t 5 i 20 05 20V GI GENERATOR
47. LAY 6 START SOLENOID 2 n HI CHOKE GASOLINE ONLY J5 V 2 SZ TBI B uc GI GENERATOR PA E3 120V Fl FUSE SLOW BLOW 10 4 ac LOAD 3 4 SPARK PLUGS 52 x LOAD E2 FUEL PUMP OR FUEL SOLENOID zi HB 2 240 Aci J6 e RED SI e 2 GOVERNOR ACTUATOR z 20 a NEUTRAL 8 CBl 2 CIRCUIT BREAKER AC OUTPUT BLACK as GND 4 5 CAPACITOR BATTERY 12V STARTER MOTOR i REMOTE CONTROL STANDARD 4 ELECTRONIC GOVERNOR Al CONTROL ASSY OPTIONAL SINGLE PHASE 60 HERTZ GENSETS BEGINNING SPEC J ITEM DESCRIPTION OR MATERIAL 611 1227 99 WIRING DIAGRAM NOTES
48. P E H JI3 1 1 K7 pa Jess i gep PI 3 Pre i 44 43 01 7 41 8 JI I JI 2 41 4 JI 3 41 6 87 87 85 1 p 5 5 5 2 JI HOUR Qc Ch Ore a7 g 2 9 4 METER TEI amp g 2 ES 3 B 77 J9 LOCAL STOP i SEE NOTE 4 gussrs ERO ws KB L EON K6 GROUND STUD aoe START 30 5 1 87 87 OPTIONAL SEE NOTE 4 gt m Br _ 1 1 1 BI T2 NBI 9 d di E 1 TE 1 1 z a 6 1 F He a Jil HOUR i 5 z MH Tr Hl P7 JI26 METER CUT FOR PI T EE pb PO T2 TRANSFORMER VOL TAGE REF KEY SWITCH J5 T eae z K7 RELAY a J8 P8 an nns ae AP EEG 1 VR2 VOLTAGE REGULATOR DC MG VRI VOLTAGE REGULATOR nm OPTIONAL COIL m 3 IGN MODULE 5 5 sts 52 SWITCH LOW OIL PRESS m L33 LOCAL SEE NOTE 5 R5 POTENTIOMETER NA d 5 RELAY 5 ae stop LOAD 6 START SOLENOID LOA HI CHOKE GASOLINE ONLY 2 5 Y GI GENERATOR 05 Aa JS Hin X bs UA Xi z 2 NEUTRA 20V FI FUSE SLOW BLOW O AMP A4 tet L Loa 7 GND 2 E3 4 SPARK PLUGS L2 2 iL SEENNOTE S EZ FUEL PUMP OR FUEL SOLENOID A As
49. R Beginning Spec L this screw is CARBURETOR Connected to LPG supply not accessible for adjustments Place soap bubble on pressure test port end of hose fitting LPG INLET 11 inch WC pressure AJ 5 4 4 3 2 1 0 3 H B 4 H e H l i HOSE T FOR TESTING for test PRESSURE INCLINED MANOMETER VENT PRESSURE BALANCE HOSE See Figure 32 for a view of the vent hose fitting when it is located on the other side FIGURE 33 LPG SUPPLY PRESSURE AND REGULATOR LOCK OFF PRESSURE 40 ELECTRIC STARTER Starter motor parts replacement kits are available for Spec J gensets Starter motor assembles for Spec H gensets do not have any replaceable or ser viceable parts requiring that the entire starter motor assembly be replaced if it does not work Starter Removal and Replacement To remove the starter for service or replacement 1 Disconnect the negative cable from the starting battery 2 Disconnect all wires and cables from the motor terminals 3 Remove the two starter mounting bolts and re move the starter SHIFT FORK PINION DRIVE HOUSING SOLENOID Replacement is the reverse of removal Torque the mounting bolts to specifications Starter Assembly and Disassembly Beginning Spec J See Figure 34 Remove the starter from the genset Remove the solenoid before disassembling the mo tor and re
50. RE 11 IGNITION COIL 19 Capacitor The ignition capacitor is secured and grounded to the top of the generator engine adaptor by one cap screw The pig tail is connected to the positive low voltage terminal of the ignition coil Spark Plugs The genset has two spark plugs The spark plugs must be in good condition and have the proper gap for top engine performance See Specifications To prevent crossthreading a spark plug always thread it in by hand until it seats Then tighten the spark plug according to Assembly Torques Alterna tively if the spark plug is being reused turn it with a wrench an additional 1 4 turn If the spark plug is new turn it an additional 3 8 to 1 2 turn If the engine misses or performance otherwise dete riorates remove and examine the spark plugs for signs of the following problems Light tan gray or reddish deposits Normal One spark plug fouled Broken spark plug cable low cylinder compression Soot fouled Wrong spark plug heat range too cold duty cycle too short for engine to reach normal operating temperature Fuel fouled Wrong spark plug heat range too cold faulty choke operation overly rich fuel mix ture dirty air filter Oil fouled Malfunctioning crankcase breather worn rings worn valve guides or seals Burned Or Overheated Leaking intake manifold gaskets lean fuel mixture Worn Spark plug service life used up 20 Quick Ignition Test If the engine
51. Stem Diameter Intake 0 2795 0 2800 0 3425 0 3430 7 099 7 112 8 700 8 712 Valve Stem Diameter Exhaust 0 2780 0 2785 0 3410 0 3420 7 061 7 074 8 661 8 687 Intake Valve Guide Diameter 0 2810 0 280 0 344 0 346 7 137 7 163 8 74 8 79 Exhaust Valve Guide Diameter 0 2805 0 2815 0 344 0 346 7 125 7 150 8 74 8 79 4 7 44 0 74 8 Valve Stem Clearance Intake 0 0010 0 0025 0 0010 0 0025 0 025 0 064 0 025 0 0 25 0 6 75 00 0 025 0 Valve Stem Clearance Exhaust 0 0020 0 0035 0 0025 0 0040 0 051 0 089 0 064 0 102 Valve Lifter Diameter 0 74575 0 7480 0 74 18 987 18 999 1 Valve Lifter Bore Diameter 0 7500 0 7515 0 7500 0 7515 19 050 19 088 19 050 19 088 Valve Lifter To Block Clearance 0 0020 0 0040 0 0020 0 0040 0 051 0 102 0 051 0 102 Intake Valve Seat Diameter Outside 1 470 1 471 1 569 1 570 37 34 37 36 39 85 39 88 Exhaust Valve Seat Diameter Outside 1 192 1 193 1 255 1 256 30 28 30 30 31 88 31 90 987 18 999 Valve Seat Bore Diameter Intake 1 4395 1 4405 1 5645 1 5655 36 563 36 588 39 738 39 764 Valve Seat Bore Diameter Exhaust 1 189 1 190 1 2510 1 2520 30 20 30 23 31 775 31 801 Assembly Torques Cylinder Head Bolts Cold Connecting Rod Bolts Rear Bearing Plate Bolts 25 27 84 37 Flywheel Mounting Nut 50 55 68 75 50 55 68 75 Stator Clamp Screws 10 12 11 16 10 12 11 16 Adapter En
52. a surements should be taken at four places the top and bottom of piston ring travel and parallel and perpendicular to the axis of the crankshaft See Figure 95 TOP OF RING TRAVEL RING WEAR AREA BOTTOM OF RING TRAVEL FIGURE 95 MEASURING CYLINDER BORE 2 Record the measurements taken at the top and bottom of the piston travel as follows A Measure and record as A the cylinder bore diameter parallel to crankshaft near the top of cylinder bore where the greatest amount of wear occurs B Measure and record as B the cylinder bore diameter parallel to crankshaft at the bot tom of piston travel C Measure and record as C the cylinder bore diameter perpendicular to crankshaft near the top of cylinder bore where the greatest amount of wear occurs D Measure and record as D the cylinder bore diameter perpendicular to crankshaft at the bottom of piston travel E Reading A subtracted from reading B and reading C subtracted from reading D indi cates the cylinder taper F Reading A compared to reading C and reading B compared to reading D indicates whether or not the cylinder is out of round If the out of round exceeds 0 003 inch 0 08 mm the cylinders must be rebored and honed to the next oversize A reboring machine is used when changing to over size pistons The following repair data de scribes the honing procedure Machining the Cylinder Bores The available oversize pistons and rings will fit w
53. a is recommended Do not tee into the fuel line This is a static pressure test 2 Push the Start Stop switch to START and hold it there for several seconds until the fuel pres sure stabilizes Fuel pressure should stabilize between 3 5 and 6 psi 24 and 41 kPa 3 Repeat the test with the vehicle engine running A fuel pressure greater than 6 psi 41 kPa is not acceptable Find out why the pressure is high If it is high when the vehicle engine is not running check to see that the proper Onan supplied pump is being used If it is high when the vehicle engine is running 34 a separate fuel pickup tube in the fuel tank or equiv alent means will be required If the fuel pressure is less than 3 5 psi 24 kPa check for fuel restrictions in the system The pump will have to be relocated closer to the fuel tank if it is located more than 3 feet 0 9 meters above the end of the fuel pickup tube in the fuel tank If the pump is defective replace it with the appropriate Onan pump The pump is not serviceable See the Installation Manual for important recom mendations regarding the fuel supply system FUEL LINE TO CARBURETOR FILTER FIGURE 27 MOUNTED FUEL PUMP LPG System Liquid Withdrawal See Figure 28 For liquid withdrawal systems the LPG container s must be equipped to withdraw LPG as a liquid See the Installation Manual for im portant recommendations regarding the installation of a LPG liquid withdrawal
54. amps Remote Control A2 A3 Optional The remote control is an optional accessory that enables the genset to be operated from a remote location Sequence Of Operation See Wiring Diagrams for the appropriate wiring schematic while working through the following de scription 1 Holding Start Stop switch 1 at Start causes Start Relay K5 to energize starter motor sole noid to crank the engine Green light Fuel Pump E1 or Fuel Solenoid FS to pump fuel or open to allow fuel to flow Green light Ignition Coil T1 to provide ignition spark The engine should start Green light Battery Current to build up the generator field through AC voltage regulator VR1 for fast build up of generator output voltage Green light Choke Heater 1 to start opening the choke to the full open running position 2 Low oil pressure cutout switch S2 should close as soon as the engine starts up It must close before the genset can continue to run 3 PMG output builds up right away and provides a signal for the control board to disconnect the starter even if the Start switch is still being held in the start position 4 The genset will continue to run when Start Stop switch 1 is released The green Generator AC light should come on 5 The red Low Battery light will probably come on during cranking but should go off during opera tion 6 Momentarily pushing Start Stop switch S1 to Stop deactivates the ignition and fuel
55. an damage the tappet bores Be careful not to strike the bores with the driver Installation 1 66 Run a small polishing rod with crocus cloth through the valve guide holes to clean out car bon and other foreign materials Place a new gasket on the intake valve guide and coat the outer edge of each new guide with anhydrous lanolin available at the drugstore Place the guide notch up in the cylinder block and press it in until the shoulder of the guide rests against the cylinder block Figure 71 WASHER PLATE 5 16 18 HEX NUT 2 REQUIRED 1 1 4 7 in 32 mm 178 mm 5 16 FLAT WASHER 2 REQUIRED 5 16 18 5 8 in THREADED 16 mm ROD FIGURE 71 SUGGESTED TOOL FOR INSTALLING THE VALVE GUIDES GEAR COVER Removal See Figure 72 Remove the flywheel flywheel key and the gear cover mounting screws See ENGINE COOLING SYSTEM under Engine Subsystems Gently tap the gear cover with a leather or plastic mallet to loosen it Installation 1 When installing the gear cover make sure that the pin in the gear cover engages the hole with GOVERNOR ARM _ GOVERNOR SHAFT YOKE WITH SMOOTH SIDE TOWARD CUP SHAFT IF FEELER WILL ENTER HOLE 1 2 IN 13 mm BALL HAS FALLEN OUT the nylon grommet in the governor cup See OIL SEALS in this section for replacing the gear cover oil seal Turn the governor cup so the hole with the ny lon grommet is at the three o clock position Use a
56. anks But Does Not Start 84 The Engine Stops When the Start Switch Is Released Beginning Spec J 87 The Engine Stops When the Start Switch Is Released Spec H Only 88 The Engine Misfires or Backfires 90 Engine Lacks Power 91 The Engine Hunts 252925 215 t eh ete ia boc i or Len 92 The Engine Overheats bep Rs uu RES 93 The Engine Has High Oil Consumption 93 The Genset Runs But There Is No Output Voltage 94 The Output Voltage Is Too High or Too Low 95 The Generator Is Noisy 4 eo wha 96 The Generator OVerhedls 96 The Phases Are Unbalanced 3 Phase Gensets 97 Genset Does Not Charge the Battery 98 WIRING DIAGRAMS epa dit 99 Single Phase 60 Hertz Gensets Beginning Spec J 99 Single Phase 50 Hertz Gensets Beginning Spec J 100 Three Phase Gensets Beginning Spec J 101 Single Phase Gasoline Fueled Gensets Spec Only 102 Single Phase LPG Fueled Gensets Spec Only 103 Three Phase Gensets Spec
57. ap ring and retainer washer in front of the crankshaft timing gear 3 Withdraw the camshaft timing gear assembly 4 Remove the oil pump 5 Bolt the gear pulling ring to the crankshaft tim ing gear using two Grade 8 1 4 20x1 inch bolts lesser grade bolts will snap off and remove the gear with a gear puller as shown Alterna tively special shoulder bolts are available for use with the flywheel puller to remove the crankshaft gear Installation 1 Service the crankshaft as necessary and rein stall it See CRANKSHAFT in this section 4 8 at 2 Preheat the crankshaft timing gear in an oven 5 to 325 F 168 ALIGN IE MARKS ee WHEN REASSEMBLING 3 Make sure the key is in place in the crankshaft THE TIMING GEARS and then tap the gear down to the shoulder on the crankshaft 4 Install the camshaft assembly Make sure the FIGURE 74 TIMING GEAR REMOVAL thrust washer is in place between the back of AND INSTALLATION 69 OIL PUMP ASSEMBLY The oil pump is mounted on the front of the crank case behind the gear cover and is driven by the crankshaft gear The inlet pipe and screen assem bly is attached to the pump body A discharge pas sage in the pump cover is aligned with a passage drilled in the crankcase that leads to the front main bearing via the oil filter A circumferential groove in the front main bearing allows oil to cross over toa drilled passage that leads to the front camshaf
58. ay Press on a new slip ring assembly with a press making sure the key is in place and the assembly is aligned with the key Solder the two rotor leads to the solder terminals on the slip ring assembly TESTING THE GENERATOR Testing the Rotor It is possible to test the rotor without removing it from the generator by removing the brush block assem bly Testing for a Grounded Winding A digital ohm meter is recommended for this test Select the high est resistance scale on the meter and touch one test probe to the rotor shaft and the other to either slip ring as shown in Figure 53 Replace the rotor as sembly if the meter does not indicate an open circuit to ground the same high resistance as when the meter probes are separated by an air gap FIGURE 54 ROTOR WINDING RESISTANCE 55 Testing Winding Resistance A digital onmmeter is recommended for measuring rotor winding resist ance Select the best scale for measuring a 20 to 25 ohm value Touch the test probes to the slip rings as shown in Figure 54 If the meter indicates a high resistance first check the connection between the slip rings and the rotor leads and resolder if necessary Replace the rotor assembly if the connections are good but the wind ing does not meet the resistance specification in Table 5 or 6 as appropriate Testing the Stator These tests can be done by disconnecting all the Tx winding leads from terminal block TB1 and the Bx and Qx win
59. bleshooting if the engine runs roughly IDLE SPEED STOP SCREW THROTTLE LEVER ALTITUDE ALTITUDE ADJUST KNOB FIGURE 18 GASOLINE CARBURETOR BEGINNING SPEC L FUEL INLET VAPOR WITHDRAWAL FUEL INLET LIQUID WITHDRAWAL IDLE SPEED STOP SCREW AND LOCKNUT THROTTLE LEVER FIGURE 19 LPG CARBURETOR BEGINNING SPEC L 27 Droop Adjustments The frequency specifications for 60 Hz gensets are followed in parentheses by the specifications for 50 Hz gensets 1 Connect rated load A Load watts is the product of volts V and amps A For Single phase Output Load watts V x A For Three phase Output Load watts 1 73 x V x A average of the three phases A 1 0 power factor obtainable with a re sistance load bank is assumed True rated output might not be obtained if appliances are used as part of the load B See Generator if output voltage cannot be adjusted to within 10 percent of rated volt age Table 3 TABLE 3 VOLTAGE SPECIFICATION RATED MAXIMUM MINIMUM OUTPUT NO LOAD FULL LOAD VOLTAGE VOLTAGE VOLTAGE H 2 64 52 1272201 3 2771480V 2 Check and adjust droop A If droop from no load frequency is more than 3 Hz 3 5 Hz for Model BGD or 4 Hz 3 5 Hz for Model NHD turn the governor sensitivity adjusting screw Figure 17 one turn counterclockwise Disconnect the load and if necessary readjust the gover nor speed adjusting screw to return to 62 63 Hz
60. ccording to the appropriate wiring diagram in Wiring Diagrams 2 Control fuse F1 on the side of the control box has blown Beginning Spec J Check for and repair ground faults in the choke heater H1 fuel pump solenoid E2 FS ignition coil T1 and remote control con nector P2 5 and P2 6 circuits See Wiring Diagrams Replace the fuse with a 10 amp slow blow mini bayonet type 3 Control board fuse F1 has blown Spec H Only Check for and repair ground faults in the starter relay K1 fuel pump solenoid E2 FS and relay K5 K6 circuits See Wiring Dia grams Replace the fuse with an Onan supplied fuse only 4 The remote control circuit if provided is faulty 5 The local Start switch circuit is faulty Try starting with the local Start switch If the engine cranks find and repair the fault in the remote control circuit Try starting with the remote Start switch if provided If the en gine cranks replace control board A1 Spec H only or the control panel assembly Beginning Spec J 81 THE ENGINE DOES NOT CRANK CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 6
61. ched 80 Exhaust System While the genset is running inspect the entire ex haust system including the exhaust manifold muf fler and exhaust pipe Look and listen for leaks at all connections welds gaskets and joints Also make sure the exhaust pipe is not overheating adjacent materials or equipment Do not run the genset until all exhaust leaks have been repaired Exhaust gas is deadly The exhaust system must not leak and must discharge all ex haust away from the vehicle Do not run the gen set until the exhaust leaks have been repaired Fuel System While the genset is running inspect the fuel supply lines return lines filters and fittings for leaks Check flexible sections for cuts cracks and abrasions and make sure they are not rubbing against anything that could cause leakage Repair all fuel leaks im mediately Gasoline and LPG are flammable and explosive Leaking fuel could lead to fire and to severe personal injury or death Repair fuel leaks immediately Control Stop and start the genset several times at the con trol panel on the genset and at the remote control board if provided to verify that they work properly Mechanical Stop the genset and inspect it for leaking gaskets loose fasteners damaged components and inter ference with other equipment Repair as necessary Inspect the generator compartment and verify that there are no breaks or openings in the vapor proof wall that separates the co
62. ci J6 2 ss BLACK LEE OPTIONAL SEE SECTION TITLED GENERATOR FOR GENERATOR CONNECTIONS LI LI L2 LO THREE PHASE GENSETS BEGINNING SPEC J SCHEMATIC un CHOKE HEATER TO THE CUSTOMER PROVIDED REMOTE ENABLE SWITCH USE 16 AWG CU WIRE 2 U ES amp LO HOKE 20 LI IGNITION FUEL PUMP GROUND PMG PMG HEATER LOW OIL PRESSURE J8 LOCAL RETURN GND RUN ELD FLASH REMOTE AVR REMOTE RUN S En Tp REMOTE RETURN GROUND REMOTE START REMOTE STOP DS ie m 5 a 4 2 1 po 4 us qp ere arera enm ee ae qe K6 B 3 3 2 1 K7 RELAY T2 TRANSFORMER VR2 VOLTAGE REGULATOR DC VRI VOLTAGE REGULATOR AC IGN COIL S3 IGN MODULE S2 SWITCH LOW OIL PRESS 2 GOVERNOR ACTUATOR 5 RELAY START SOLENOID CHOKE GASOLINE ONLY GENERATOR FI FUSE SLOW BLOW 10 AMP 4 SPARK PLUGS E2 FUEL PUMP OR FUEL SOLENOID CBI 3 CIRCUIT BREAKER A
63. circuit breakers CB1 CB2 and CB3 as shown in the appropriate diagram in Figure 59 60 or 61 It should be noted that other leads are also connected to terminal block TB1 in the control box and that they should be reconnected as marked if inadvertently disconnected FIGURE 57 BRUSH BLOCK ASSEMBLY FIGURE 58 VOLTAGE REGULATOR TERMINALS 1 PHASE GENSETS 3 WIRE 60 HZ 120 240 VAC 110 120 il 220 240 VAC BLACK CB1 LOAD WHITE NEUTRAL BLACK CB2 LOAD GREEN GND TROL BOX 2 WIRE 60 HZ 120 VAC 110 120 VAC BLACK CB1 LOAD BLACK CB2 LOAD A WHITE WHITE NEUTRAL GREEN GND CONTROL BOX 2 WIRE 60 HZ 240 VAC 1 2 220 240 VAC BLACK CB2 LOAD WHITE NEUTRAL GREEN GND CONTROL BOX wi INSTALLER MUST PROVIDE NO 12 AWG TYPE XLPE CONDUCTOR
64. cket If this is a LPG genset equipped for liquid with drawal disconnect the fuel vaporizer the tub ing wrapped around the manifold at both ends and remove the pressure regulator Bending the fuel vaporizer tub ing can weaken it to the point that it can crack allowing LPG under high pressure to escape resulting in possible severe per sonal injury or death Large volumes of LPG can be released in the process of disconnecting a liquid with drawal type of LPG supply system See Preparations Page 12 for the proper pro cedures and precautions 4 Remove the four exhaust manifold bolts Lift off the exhaust manifold and the two manifold gas kets Reassembly is the reverse of disassembly Always use new manifold gaskets when reassembling and torque the manifold bolts according to Assembly Torques i FIGURE 6 EXHAUST MANIFOLD ENGINE COOLING SYSTEM See Figure 7 These are air cooled gensets The engine flywheel is also a centrifugal blower that draws cooling air across the fins on the engine cylin ders and heads and discharges the warm air down wards through the discharge grill Disassembly 1 Remove the muffler see EXHAUST SYS TEM 2 Remove the capscrews that secure the noise shield and lift off the noise shield 3 Remove the three nuts along the lower edge of the blower scroll that hold the discharge grill to the scroll 4 Remove the capscrews that fasten the blower scroll to the backplat
65. ct the load check for zero amps Pull the governor rod so that the tang on the throttle lever bears against the idle speed stop screw Adjust the screw to obtain 54 56 Hz 44 46 Hz Idle Mixture and Frequency Adjustments The frequency specifications for 60 Hz gensets are fol lowed in parentheses by the specifications for 50 Hz gensets 1 Disconnect all loads check for zero amps Then check no load frequency If necessary turn the governor speed adjusting screw to ob tain a no load frequency of 62 63 Hz 51 5 52 5 Hz IDLE MIXTURE ADJUSTING SCREW CAP THROTTLE iak sl LEVER E 5 MAIN FUEL MIXTURE ADJUSTING SCREW CAP ALTITUDE SCALE FIGURE 20 GASOLINE CARBURETOR PRIOR TO SPEC L IDLE SPEED STOP SCREW MAIN FUEL MIXTURE ADJUSTING SCREW THROTTLE LEVER FIGURE 21 LPG CARBURETOR PRIOR TO SPEC L 29 TABLE 4 VOLTAGE SPECIFICATION RATED MAXIMUM MINIMUM OUTPUT NO LOAD FULL LOAD VOLTAGE VOLTAGE VOLTAGE 120 IPH 120 240V 1PH 264 224 2 Turn the idle mixture adjusting screw clockwise until the frequency drops and then counter clockwise until it drops again Adjust it to obtain the highest possible stable frequency Some wander is normal For closer adjustments use a CO meter to adjust to 6 8 CO gasoline or 4 6 CO LPG See Troubleshooting if the engine runs roughly 252 236 364 232 202 504 340 3 Push the adjustment limiter cap on over the mixture scre
66. ding leads from their connectors Single phase generators have winding lead pairs T1 T2 T3 T4 and Q1 Q2 Three phase generators have lead pairs T1 T4 T2 T5 T3 6 T7 T10 T8 T11 and T9 T12 Spec H generators also have lead pair B1 B2 Alternatively a plug in tester is available for conducting stator winding tests Testing for a Grounded Winding A digital ohm meter is recommended for this test Select the high est scale on the meter Test each lead as shown in Figure 55 Replace the stator assembly if any read ing is low indicating a breakdown in the winding in sulation Testing Winding Resistance A digital onmmeter can be used to determine if a stator winding is open as shown in Figure 56 A Wheatstone Kelvin bridge should be used to measure stator winding re sistance Replace the stator assembly if any wind ing is open or does not meet the resistance specifi cation in Table 5 or 6 as appropriate 56 FIGURE 55 STATOR INSULATION RESISTANCE FIGURE 56 STATOR WINDING CONTINUITY Checking Open Circuit Output Voltage Alterna 4 Connect brush block terminal B outboard to tively check the open circuit output voltage VAC of the positive battery terminal on the genset each stator winding as follows K1 B This jumper should have a 10 amp fuse and switch 1 If necessary service the brushes slip rings and rotor and adjust for rated frequency 5 Measure the output across each lead pair while 2 Disconnec
67. e Plasti Gage bearing clearance guide Spark plug gap gauge Oil pressure gauge 0 30 psi 0 200 kPa Fuel pressure gauge for gasoline 0 10 psi 0 75 kPa Manometer for LPG 14 inch 850 mm WC Inclined Manometer for LPG 1 inch 25 mm WC range with 0 01 inch 0 1 mm WC divisions Cylinder compression tester Flywheel puller Crankshaft gear puller ring bolts and puller or special shoulder bolts and flywheel puller Snap ring pliers Combination main and cam bearing remover Combination main and cam bearing driver Oil seal loader and driver Cylinder ridge reamer Piston ring spreader Piston groove cleaner Piston ring compressor Cylinder hone Valve spring compressor Valve lock replacer Valve seat cutter kit Valve guide driver Slide hammer Lead or dead blow hammer Generator and Control Tools Rotor removal tool headless bolt Commutator stone Battery hydrometer Frequency meter Digital multi meter AC and DC Voltage Ohms and Diode Check Load test panel and leads Voltage Regulator Testor and Adaptor 1 Ph Rotor and Stator Testor and Adaptor REMOVING THE GENSET Some service procedures will require that the gen set be removed from the vehicle The genset is nor mally mounted in a special compartment on the ve hicle floor Because installations vary it is not pos sible to describe a specific removal procedure Con tact the vehicle manufacturer or installer if the best way to remove the
68. e Start switch and measure the voltage at the positive 4 terminal on the ignition coil If there is at least 9 VDC service the ignition system as necessary If there is not at least 9 VDC go to Step 7 or 8 as ap propriate 7 Control board A1 is faulty If there is not at least 9 VDC at the ignition coil during cranking Spec H LPG Step 6 see TESTING CONTROL BOARD 1 in Engine Con trol Replace parts or reconnect leads as necessary 8 Relay K6 or control A1 is If there is not at least 9 VDC at the ignition coil during cranking faulty Spec H Gasoline Step 6 remove the lead at terminal 85 on relay K6 Hold in the Start switch and measure the voltage at the end of the lead just disconnected If there is at least 9 VDC verify that all the leads at relay K6 are connected according to the appropriate connection dia gram in Wiring Diagrams lf they are replace relay If there is not at least 9 VDC at the end of the lead marked K6 85 check all the connections back to control board A1 and see TESTING CONTROL BOARD A1 in Engine Con trol Replace parts or reconnect leads as necessary 9 The choke is not closing Service as instructed in FUEL SYSTEM in Engine Subsystems properly in colder weather Gasoline carburetors only 10 The engine is not getting If the Fuel Pump indicator lights during cranking but you cannot fuel because the fuel sole hear or feel the solenoid open or the pump vibrate test the fuel no
69. e and pull away the scroll 5 Remove the screws that fasten the cylinder shrouds to the back plate and cylinder heads and lift them off 6 Loosen the flywheel capscrew and back it out several turns See Figure 8 7 Attach the puller tool to the flywheel The tool has two jack screws that fit into the holes tapped in the flywheel 8 Tighten the puller center screw until the fly wheel comes loose Remove the puller fly wheel center screw and washer Remove the flywheel carefully so as not to damage the PMG Inspect the flywheel and replace it if any air vanes are missing or magnets are loose or missing Figure 9 9 Remove the lead from the low oil pressure cut off switch 10 Remove the exhaust manifold see EXHAUST SYSTEM 11 Remove the capscrews that hold the backplate to the engine Lift off the backplate 12 Use a brush or low pressure compressed air to remove accumulated dust on the engine cool ing fins BLOWER SCROLL NOISE SHIELD DISCHARGE FLYWHEEL GRILL BLOWER BACKPLATE FIGURE 7 COOLING SYSTEM FLYWHEEL FLYWHEEL PULLER FLYWHEEL CAPSCREW FIGURE 8 FLYWHEEL REMOVAL 17 Reassembly Reassembly is the reverse of disas sembly When installing the flywheel align its key way with the woodruff key on the crankshaft Use non hardening sealer on the flywheel capscrew threads and torque to 50 55 Ibs ft 68 75 N m The engine will overheat and can be damaged if it is operated
70. e drip tray using one EIT external internal toothed lock washer on each side of the strap terminal for a good electrical connection 7 Reconnect or reassemble all other parts that were disconnected or removed Do not forget to refill the crankcase with the appropriate grade of engine oil after the genset has been re installed in the vehicle See the Op erator s Manual for engine oil recommenda tions GENERATOR ASSEMBLY DISASSEMBLY Removing the Rotor from the Generator 1 Remove the generator from the genset as instructed under Removing the Generator from the genset 2 To keep from damaging the brushes and to keep them from interfering when inserting the rotor either A Remove the brush block assembly by dis connecting the leads marked F1 and F2 from the brush block terminals and then re moving the two mounting screws B Insert a stiff wire into the small hole in the end of the stator housing to hold the brushes up and out of the way Figure 50 To do this first pull both brush pigtails to lift the brushes off the slip rings 3 Turn the generator over onto its bearing end and withdraw the rotor straight up It may be necessary to have an assistant hold down the generator housing Be careful not to nick the stator windings with the rotor while withdrawing the rotor INSERT A RETAINING WIRE TO KEEP THE BRUSHES OUT OF THE WAY WHEN ASSEMBLING AND DISASSEMBLING THE GENERATOR WIRE FIGURE
71. e of at least 14 inches 350 mm 3 Open the LPG container shutoff valve and try starting the genset 4 While the genset is running check the manom eter and adjust the LPG supply pressure regu lator to obtain 11 inches 279 mm WC If there is a secondary pressure regulator in the supply line adjust the secondary regulator instead of the primary regulator at the LPG container 5 If the genset will not start jumper the fuel sole noid to the battery cable connections on the genset so that it stays open the regulator will keep gas from flowing and then check and ad just the LPG supply pressure 6 If the genset is operable check LPG supply pressure under full load If it drops below the minimum required pressure either the LPG container is too small to provide the rate of va porization necessary or it is less than half full or the supply line is too restrictive 7 Disconnect any jumpers which may have been used to energize the fuel solenoid and thread in and tighten the pressure test port plug unless tests are going to be continued Fuel Shutoff Solenoid Valve Replace the fuel so lenoid if it fails to open as indicated by the absence of gas pressure on the manometer scale in the pre vious test when it is jumpered across the the bat tery cable connections at the genset Demand Regulator Lock Off Pressure Test Lock off pressure is determined as follows by pres surizing the back vent side of the regulator dia
72. e of critical passages THROTTLE PLATE MAIN FUEL mec cei MIXTURE ADJUSTIN FLOAT ASSEMBLY FIGURE 22 GASOLINE CARBURETOR PRIOR TO SPEC L THROTTLE SHAFT GASKET FIGURE 23 LPG CARBURETOR PRIOR TO SPEC L 31 Reassembly 1 32 Slide in the throttle shaft and install the throttle plate using new screws if they are furnished in the repair kit Before tightening the screws the plate must be centered in the bore To do this back off the throttle stop screw as necessary and completely close the throttle lever Seat the plate by gently tapping it with a small screwdriv er then tighten the screws Install the choke shaft and plate in the same manner See Figure 24 Turn the carburetor upside down and install the new needle valve float float hinge pin and fuel bowl gasket in the repair kit Make sure the wire clip properly engages the groove around the end of the needle valve and loops around the metal tang of the float The clip pulls down on the needle valve when the float level drops breaking the needle loose if itis stuck Check to see that the float moves freely without binding See Figure 25 Check float level as shown while the carburetor is still upside down Measure the height above the bowl gasket flange on the side opposite the hinge Make sure the full weight of the float is resting on the needle valve Remove the float and bend the metal tang to adjust the height Remov
73. e pistons showing signs of scuffing scoring worn ring lands fractures or damage from pre igni tion Connecting Rod Inspection Replace connecting rod bolts and nuts having damaged threads Re place connecting rods with deep nicks signs of frac tures scored bores or bores out of round more than 0 002 inch 0 05 mm Use a new piston pin to check the connecting rod for wear A push fit clearance is required this varies from engine to engine If a new piston pin falls through a dry rod pin bore as a result of its own weight replace the rod or bushing as required Piston Pin Inspection Replace piston pins that are cracked scored or out of round more than 0 002 inch 0 05 mm Bearing Inspection Inspect bearings for burrs breaks pitting and wear Replace bearing inserts which are scored have their overlay wiped out show fatigue failure or are badly scratched If the bearings appear to be serviceable check them for proper clearance Piston Clearance Correct piston tolerances must be maintained Use a micrometer to measure the piston diameter at the point shown in Figure 81 When the cylinder bore is measured see CYLINDER BLOCK subtract the piston diameter from the cylinder bore diameter to obtain the piston to cylinder wall clearance See Tolerances and Clearances 72 FIGURE 79 CHECKING RING LAND CYLINDER WALL IMPROPER RING CONTACT FIGURE 80 NEW RING IN WORN RING GROVE MEASURE DIAMETER
74. e the contents of the fuel supply tank if there is a noticeable improvement in performance 7 The engine air filter element Replace the air filter element is dirty 8 The exhaust system is re Service as necessary stricted 9 The valve adjustment is in Adjust according to Adjusting Valve Clearance Lash under correct VALVE SYSTEM in Engine Block Assembly 10 The engine is worn or mal Do the CYLINDER COMPRESSION TEST in Engine Subsys functioning mechanically tems and service as necessary according to Engine Block As sembly THE ENGINE HUNTS There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 Fuel mixture prior to Spec L Adjust according to Governor and Carburetor Adjustments under only and governor adjust FUEL SYSTEM in Engine Subsystems ments are incorrect 2 The governor spring is Replace the spring weak 3 The governor mechanism is Service as necessary according to GEAR COVER and GOVER worn NOR CUP in Engine Block Assembly 92 THE ENGINE OVERHEATS There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be pe
75. e the float before bend ing the tang so as not to damage the soft nose of the needle valve Install the float bowl and the main mixture screw assembly Install the idle and main fuel mixture screws Turn them lightly by hand until they seat Then For Gasoline Gensets Turn the idle mixture screw out 1 turn and the main fuel mixture screw out 1 1 4 turns so that the engine will start and run 0 59 0 63 INCH For LPG Gensets Turn the idle mixture screw out 1 1 4 turns and the main fuel mixture screw out 2 1 2 turns so that the engine will start and run WIRE CLIP NEEDLE VALVE HINGE PIN METAL TANG FLOAT FLOAT HINGE PIN RETAINING SCREW FIGURE 24 FLOAT INSTALLATION GASOLINE BEND METAL TANG TO 15 16 mm ADJUST FLOAT HEIGHT THE FULL WEIGHT OF THE FLOAT MUST REST ON THE NEEDLE VALVE WHILE MEASURING FLOAT HEIGHT FIGURE 25 FLOAT LEVEL GASOLINE Automatic Choke Gasoline Sets See Figure 26 The automatic choke is operated by a bi metal heater assembly and a vacuum breaker assembly Replace faulty choke components and reassemble as shown Adjust the choke breaker as sembly each time it is assembled to the carburetor as follows CAUTION Make sure this hose is not kinked may cause engine to flood and does not in terfere with the choke shaft assembly VACUUM SUSTAIN VALVE ASSEMBLY Apply a vacuum of at least 4 inches 100 mm of mercury to fully pull in the choke br
76. eads erator s Manual 2 The ignition system is faulty Service the ignition system as necessary according to IGNITION SYSTEM in Engine Subsystems 3 Fuel mixture and governor Adjust according to Governor and Carburetor Adjustments under adjustments are incorrect FUEL SYSTEM in Engine Subsystems b Check for and repair a vacuum leak c Overhaul prior to Spec L only or replace the carburetor accord ing to FUEL SYSTEM in Engine Subsystems 4 The gasoline fuel pump is Verify that the fuel pump is not more than 3 feet 9 m in elevation not installed properly above the pickup tube in the fuel supply tank If it is relocate the fuel pump according to the instructions in the Installation Manual 5 The fuel filter s is clogged Replace clogged gasoline filters and clean out LPG filters and regulators See LPG System Liquid Withdrawal under FUEL SYSTEM in Engine Subsystems 91 THE ENGINE LACKS POWER CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 6 The fuel gasoline is con Connect the genset to a container of known fuel quality and run taminated the genset under various loads Replac
77. eaker arm Insert a 0 337 inch 8 6 mm drill rod between the choke plate and the carburetor throat If necessary bend the link at the point shown until the lip of the choke plate just touches the drill rod Use two pliers to bend the link IF NECESSARY BEND THIS LINK AT THIS POINT WHEN ADJUSTING THE CHOKE BREAKER ASSEMBLY CHOKE BREAKER ASSEMBLY ASSEMBLY GAUGE THE DISTANCE BETWEEN THE CHOKE PLATE AND THE CARBURETOR THROAT WITH A BI METAL HEATER 0 337 INCH 8 6 mm DRILL ROD WHEN ADJUSTING CARBURETOR ASSEMBLY THE CHOKE BREAKER ASSEMBLY FIGURE 26 CHOKE ASSEMBLY 33 Fuel Pump Gasoline Gensets See Figure 27 The fuel pump might be mounted on the genset or at a remote location on the vehicle The pump delivers fuel to the carburetor at 3 5 5 psi 24 35 kPa and has a lift capacity suction of 3 feet 0 9 meters Do not substitute an automotive fuel pump for the standard pump removed from the genset Other pumps can cause carburetor flooding because of the high pressures they de velop Carburetor flooding can cause poor per formance and engine damage and lead to pos sible fire and severe personal injury or death Fuel pressure at the carburetor fitting must not exceed 6 psi 41 kPa under any operating con dition Fuel Pressure Test 1 Disconnect the fuel line at the outlet of the fuel pump and connect a pressure gauge at the pump outlet A gauge calibrated for 0 15 psi 0 100 kP
78. earance 0 003 0 008 0 002 0 008 0 076 0 203 0 051 0 203 Piston Pin Diameter 0 6875 0 6877 0 7500 0 7502 17 46 17 47 19 05 19 06 0 0 0 5 2 5 2 0 005 0 002 0 016 0 002 0 016 0 051 0 406 0 051 0 406 0 0020 0 0 002 0 0033 0 051 0 084 0 051 0 084 1 9992 2 0000 1 9992 2 0000 50 780 50 800 50 780 50 800 Crankshaft Rod Journal Bearing Diameter 1 6252 1 6260 1 6252 1 6260 41 280 41 300 41 280 41 300 Crankshaft Bearing Diameter 2 0024 2 0034 2 0015 2 0040 50 860 50 886 50 838 50 902 Crankshaft Main Bearing Clearance 0 0024 0 0042 0 0024 0 0042 0 061 0 107 0 061 0 107 Crankshaft End Play 0 006 0 012 0 006 0 012 0 15 0 30 0 15 0 30 The bore is 0 005 inch oversize if the engine serial number has suffix All dimensional tolerances and clearances are in inches millimeters unless otherwise indicated MODEL BDG MODEL NHD Camshaft Journal Diameter 1 3740 1 3745 1 3740 1 3745 34 90 34 91 34 90 34 91 Camshaft Bearing Diameter 1 376 1 377 1 376 1 377 34 95 34 97 34 95 34 97 Camshaft Bearing Clearance 0 0015 0 0030 0 0015 0 0030 0 038 0 076 0 038 0 076 Camshaft End Play 0 011 0 048 0 011 0 048 0 28 1 2 0 28 1 2 Valve Spring Free Length 1 600 1 662 40 64 42 21 Valve Spring Compressed Length Valve Closed 1 346 1 375 34 19 34 92 Valve Spring Tension Open 55 Ibs 71 16 25 kg 32 kg Valve Spring Tension Closed 25 lbs 38 16 11 kg 17 kg Valve
79. efore installing the new seals Use an oil seal guide and driver to drive the rear seal into the rear bearing plate until it bottoms against the shoulder of the plate Drive the front oil seal into the gear cover until it is 0 95 0 99 inch 24 1 25 1 mm from the mounting face of the cover Place a light coating of grease on the lips of the seals before installing the rear bearing plate and gear cover This provides initial lubrication until en gine oil reaches the seal Refer to CRANKSHAFT for the rear bearing plate installation procedure Re fer to GEAR COVER for the gear cover installation procedure DRIVE THE OIL SEAL TO THE SHOULDER OF THE PLATE BORE MOUNTING FACE OF GEAR COVER DRIVE THE OIL SEAL THUS FAR INTO THE GEAR COVER BORE 2277 FIGURE 94 FRONT GEARCASE CRANKSHAFT OIL SEAL 77 ENGINE BLOCK The engine block is the main support for all other ba sic engine parts and subassemblies Cleaning After removing the pistons crankshaft cylinder heads etc inspect the block for cracks and ex treme wear If it is still serviceable prepare it for cleaning as follows 1 Scrape all old gasket material from the block Remove oil bypass to allow cleaning solution to contact inside of oil passages 2 Remove grease and scale from the cylinder block by agitating in a bath of commercial cleaning solution or hot soapy washing solu tion 3 Rinse the block in clean hot water to remove cleaning solution
80. elow Freezing 360 450 amperes 360 450 amperes Nominal Regulated Voltage Battery Charging Output 10 amperes 10 amperes Control Fuse F1 Beginning Spec J 10 amperes mini bayonet 10 amperes mini bayonet Control Fuse F1 Spec H only 5 amperes slow blow 5 amperes slow blow Ignition Choke F2 Spec only 10 amperes mini bayonet 10 amperes mini bayonet See Periodic Maintenance for oil filling instructions Tolerances and Clearances All dimensional tolerances and clearances are in inches millimeters unless otherwise indicated MODEL BDG MODEL NHD Cylinder Bore Standard Size 3 2490 3 2500 3 5625 3 5635 82 52 82 55 90 49 90 51 Cylinder Taper maximum 0 005 0 003 0 13 0 08 Cylinder Out of Round maximum 0 003 0 003 0 08 0 08 Clearance in Cylinder 0 0033 0 0053 0 0070 0 0090 0 084 0 135 0 178 0 229 Ring Gap 0 010 0 020 0 010 0 020 0 25 0 50 0 25 0 50 1 Top Piston Ring Groove Width 0 0602 0 0612 0 0602 0 0612 1 53 1 55 0 25 0 50 2 Piston Ring Groove Width 0 0602 0 0612 0 0602 0 0612 1 53 1 55 1 53 1 55 3 Piston Ring Groove Width 0 1193 0 1203 0 1193 0 1203 3 03 3 06 3 03 3 06 1 Top Piston Ring Groove Width Prior to Spec F 0 080 0 081 0 080 0 081 2 03 2 06 2 03 2 06 2 Piston Ring Groove Width Prior to Spec F 0 080 0 081 0 080 0 081 2 03 2 06 2 03 2 06 3 Piston Ring Groove Width Prior to Spec F 0 188 0 189 0 188 0 189 4 78 4 80 4 78 4 80 1 Top Piston Ring Side Cl
81. er in the same cylinder 5 The pistons are fitted with two compression rings and one oil control ring Remove these rings from the piston using a piston ring spread er Figure 77 6 Remove the piston pin retainer from each side and push the pin out 7 Remove dirt and deposits from the piston sur faces with an approved cleaning solvent Clean the piston ring grooves with a groove cleaner or with the end of a piston ring filed to a sharp point Figure 78 Take care not to remove met al from the sides of the grooves Using a caustic cleaning sol vent or wire brush for cleaning pistons will cause piston damage Use only parts clean ing solvent for this job When cleaning the connecting rods in solvent make certain to include the rod bore Blow out all passages with low pressure compressed air FIGURE 76 CYLINDER RIDGE REAMER FIGURE 77 PISTON RING SPREADER FIGURE 78 PISTON RING GROVE CLEANER 71 Piston and Connecting Rod Inspection Piston Inspection Inspect the pistons for fractures at the ring lands skirts and pin bosses Check for wear at the ring lands using a new ring and feeler gauge Figure 79 Replace the piston if the side clearance of the top compression ring is 0 008 inch 0 20 mm or more Improper ring width or excessive ring side clearance can result in ring breakage New rings in worn ring grooves do not make adequate contact with the cyl inder wall Figure 80 Replac
82. f de vices are plugged in even if the device has been switched OFF These circuits can be dam aged by variations in voltage and frequency GOVERNOR SPRING GOVERNOR ROD GOVERNOR SENSITIVITY ADJUSTING SCREW DROOP BALL AND SOCKET GOVERNOR SPEED ADJUSTING SCREW Consequential damage to TVs VCHs comput ers and other voltage and frequency sensitive devices as a result of failing to observe this pre caution is not covered under the Onan warranty policy Governor Rod Length Adjustment The length of the governor rod Figure 17 must be checked and adjusted as follows before other adjustments are at tempted 1 Loosen the lock nut at the ball joint end of the governor rod and unsnap the socket from the ball 2 Push the governor rod gently towards the car buretor full throttle position While keeping it there turn the socket as necessary to length en or shorten the rod so that the ball and socket line up Too much pressure on the rod can result in a faulty adjustment of the rod length 3 Snap the socket back over the ball 4 Tighten the lock nut while holding the socket square with the axis of the ball Also the leg at the throttle end of the rod must be kept level 5 Gently rotate the governor arm and check for binding If necessary loosen the locknut and repeat Step 4 until the linkage moves smoothly Binding can cause erratic governor action DETAIL GASOLINE AND LPG VAPOR WITHDRAWAL
83. f ignition well away Gasoline Fueled Gensets Disconnect the fuel line from the genset and securely plug the end of the fuel line to prevent leakage or an ac cumulation of explosive gasoline vapor LPG Fueled Gensets Close the fuel shutoff valve s at the LPG container s and move the vehicle outside and away from below grade spaces where LPG could accumulate To purge the fuel line and genset as much as possible run the genset if it starts until it runs out of fuel with the LPG valve s closed LPG is flammable and explo sive and can cause asphyxiation NFPA 58 Section 1 6 requires all persons handling LPG to be trained in proper handling and operating procedures LPG sinks when it escapes into the air and can accumulate in explosive con centrations Before disconnecting the LPG fuel line close the fuel shutoff valve s at the LPG container s and move the vehicle outside and away from pits or basements or other below grade spaces where LPG could accumulate For LPG liquid withdrawal systems see Figure 28 on Page 35 press the regulator priming but ton while cranking for 10 seconds to purge some of the remaining LPG Then loosen the threaded flexible fuel supply hose connector at the fuel filter on the genset just enough to hear gas escaping Unthread the connector when no more gas is heard escaping Finally cap the end of the fuel supply hose with a 1 4 inch NPTF pipe cap to prevent fuel from escaping if someone
84. fore working on the genset disconnect the nega tive battery cable at the battery to prevent start ing Use caution when making adjustments while the genset is running hot moving or electrically live parts can cause severe personal injury or death Used engine oil has been identified by some state and federal agencies as causing cancer or repro ductive toxicity Do not ingest inhale or contact used oil or its vapors e Benzene and lead in some gasolines have been identified by some state and federal agencies as causing cancer or reproductive toxicity Do not to in gest inhale or contact gasoline or its vapors e Do not work on the genset when mentally or physi cally fatigued or after consuming alcohol or drugs e Carefully follow all applicable local state and feder al codes GENERATOR VOLTAGE IS DEADLY Generator output connections must be made by a qualified electrician in accordance with applicable codes e The genset must not be connected to the public util ity or any other source of electrical power Connec tion could lead to electrocution of utility workers damage to equipment and fire An approved switch ing device must be used to prevent interconnec tions Use caution when working on live electrical equip ment Remove jewelry make sure clothing and shoes are dry and stand on a dry wooden platform on the ground or floor FUEL IS FLAMMABLE AND EXPLOSIVE e Keep flames cigarettes spa
85. g as necessary See Wiring Diagrams If there is B at terminal 30 remove the relay from its socket and apply battery voltage across coil terminals 85 and 86 If the coil does not function or if there is no electrical con tinuity between terminals 30 and 87 when the relay is energized replace the relay If the relay is good replace the control panel assembly 82 THE ENGINE DOES NOT CRANK CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action Spec H Only 9 Control board 1 or start Remove the control panel Push the Start Stop switch to Start relay K1 is faulty and measure voltage at start solenoid terminal S If there is not at least 9 VDC see TESTING CONTROL BOARD A1 in Engine Control Replace parts or reconnect leads as necessary If there is at least 9 volts at terminal S push the Start Stop switch to Start again and measure voltage at the motor ter minal on the start solenoid If there is no voltage at the motor terminal replace relay K1 The cable between start Service as necessary relay K1 and the starter motor is loose damaged or missing The starter motor is mal Push the
86. genset is not obvious Disconnections at the Genset 1 Disconnect couplings First disconnect the negative battery cable from the battery and then disconnect the bat tery cables from the genset Sparks and high current could cause fire and other damage to the battery battery cables and vehicle if the loose ends of cables connected to the battery touch Always disconnect the negative battery cable from the battery before disconnecting the battery cables from the genset Disconnect the remote control wiring harness connector at the genset Disconnect the generator output wiring and conduit from the power distribution panel or box on the vehicle Tag all wires to make reconnec tions easier Disconnect the exhaust tailpipe from the outlet of the muffler and then remove the muffler See EXHAUST SYSTEM under Engine Subsys tems adapters hydraulic lines and other power takeoff attachments on gensets so equipped 11 6 Disconnect the fuel line from the genset Follow 12 the applicable instructions depending on the fuel Gasoline and LPG liquified pe troleum gas are flammable and explosive and can cause severe personal injury or death Do not smoke if you smell gas or gas oline or are near fuel tanks or fuel burning equipment or are in an area sharing ventila tion with such equipment Keep flames sparks pilot lights electrical arcs and arc producing equipment and all other sources o
87. ges normally when the Start switch is held in The problem is probably low oil pressure or a faulty pressure sender Go to Step 2 if the starter does not disengage when the Start switch is held in The problem is prob ably in the PMG or its connections 1 The engine oil pressure is a Check engine oil level and fill as necessary Go to the next step low or the cutout switch is if the engine still does not continue to run when the start switch faulty The starter disen is released gages normally when the Bypass low oil pressure cutout switch S2 by disconnecting the Start switch is held in CUOU S y di ing lead to it and grounding it For access remove the cylinder head shroud on the oil filter side Start the genset If oil pressure is at least 12 psi replace low oil pressure cut out switch 52 If oil pressure is less than 12 psi service the engine accord ing to LUBRICATION SYSTEM in Engine Block Assembly 2 The PMG is faulty or not Disconnect connector J8 P8 in the wiring harness in the vicinity connected properly The of the ignition coil and connect an ohmmeter to check PMG stator starter does not disengage winding continuity Replace the PMG stator if the windings are when the Start switch is open normal winding resistance is approximately 0 13 ohms held in See PMG in Engine Subsystems If winding continuity is good connect an AC volt meter to the PMG stator leads start the engine hold
88. gine Mounting Bolts 25 27 34 37 25 27 34 37 Adapter Generator Mounting Bolts 25 34 25 34 Rear Vibration Isolators Center Bolt Flange to Drip Tray Screws Front Vibration Isolators Center Bolt 28 32 38 43 28 32 38 43 Flange to Oil Base Screws 19 22 26 30 19 22 26 30 Use engine oil as a lubricant for all threads EXCEPT for spark plug and rotor through bolt threads Preparations TROUBLESHOOTING check its condition before starting Comply with the warnings in this manual and take special See Troubleshooting to determine the probable precautions when working around electrical cause of the problem before removing the genset equipment Do not work alone if possible and for service take no risks SAFETY e Be prepared for an accident Keep fire extin guishers and safety equipment nearby Agen There are hazards in servicing gensets Study Safe cies such as the Red Cross and public safety ty Precautions and become familiar with the haz departments offer courses in first aid CPR and ards listed in Table 2 Note the following safeguards fire control Take advantage of this information and ways of avoiding hazards to be ready to respond to an accident Learn to be safety conscious and make safety proce Use personal protection Wear appropriate dures part of the work routine protective safety equipment such as TABLE 2 HAZARDS AND THEIR SOURCES Safety shoes Leaking or spilled fuel Gloves Fire and gas fro
89. gni tion coil if secondary resistance is not between 10 000 and 40 000 ohms See Figure 12 FIGURE 12 TESTING THE IGNITION COIL 21 CRANKCASE BREATHER ASSEMBLY See Figure 13 The crankcase breather is a reed valve assembly that opens to discharge crankcase vapors on the piston down stroke and closes on the up stroke resulting in a negative pressure in the crankcase when the engine is running The crank case vapors blowby gases gasoline vapors mois ture air are routed to the carburetor for burning in the cylinders A dirty or sticking valve can cause oil leaks high oil consumption rough idle reduced en gine power and sludge formation within the engine Disassembly The breather assembly is serviced by disassembling it and cleaning all the parts in parts cleaning solvent The assembly comes apart when the capscrew is unscrewed Most parts cleaning solvents are flammable and corrosive and can cause severe burns and inflammation Use only as recom mended by the manufacturer Reassembly Reassemble using a new gasket Replace the reed valve if it does not lie flat across the discharge orifice Torque the cover capscrew to 12 24 16 1 3 2 6 N m Over tightening the capscrew can distort the cover allowing dirt and air to enter the engine 22 BREATHER HOSE CAPSCREW FLAT WASHER SPRING COPA FLAT WASHER GASKET BREATHER BAFFLE FIGURE 13 CRANKCASE BREATHER ASSEMBLY LUBRICATION SYSTEM
90. h WC 3 8 and 6 4 mm WC Unauthorized modifications or replacement of fuel exhaust air intake or speed control system components that af fect engine emissions are prohibited by law in the State of California 39 For Gensets Prior to Spec L Adjust lock off test lock off pressure again Repeat the pressure as follows procedure if necessary f the lock off pressure is greater than 0 25 e Replace the demand regulator if it contin inches 6 4 mm WC remove the locking ues to leak after lock off pressure adjust screw and back out the adjusting screw ments have been attempted counterclockwise until the lock off pres 4 If If the genset is mounted a compartment 3 a 4 make sure the vent pressure balance hose is screw and test lock off pressure again Re property lo Ine outside peat the procedure if necessary 5 Reconnect the hose to the carburetor discon nect any jumpers which may have been used to energize the fuel solenoid and thread in and tighten the pressure test port plug f the lock off pressure is less than 0 15 inch 3 8 mm WC remove the locking screw and turn in the adjusting screw clockwise until the lock off pressure falls 6 For gensets prior to Spec L adjust fuel mixture between 0 15 and 0 25 inch WC 3 8 and as instructed under Governor and Carburetor 6 4 mm WO Set the locking screw and Adjustments in this section LOCK OFF ADJUSTING SCREW LPG OUTLET TO MANOMETE
91. hooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 8 Voltage Regulator VR1 is Measure voltage between VR1 connector pin 9 connector J10 faulty on 3 phase gensets and ground while cranking the engine If there is less than 9 VDC replace output voltage regulator VR1 If there is at least 9 VDC measure resistance between VR1 connector pin 10 connector J11 on 3 phase gensets and ground Replace output voltage regulator VR1 if there is measurable resistance greater than zero 9 Generator output too low See OUTPUT VOLTAGE IS TOO HIGH OR TOO LOW THE ENGINE MISFIRES OR BACKFIRES There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The ignition system if faulty Service the ignition system as necessary according to IGNITION SYSTEM in Engine Subsystems 2 The fuel mixture is too lean a Adjust fuel mixture prior to Spec L only according t
92. hould fall between 25 and 100 volts DC and be stable at constant load If field voltage fluctuates at constant load a possible governor or voltage regulator problem exists See Troubleshooting TESTING 1 PH VOLTAGE REGULATORS See Figure 58 Confirm that the voltage regulator VR1 is faulty before replacing it Use the tester available or a meter with a diode checking function Fluke Model 73 Multimeter for example to perform the following tests 1 Disconnect the negative battery cable 2 Remove the generator control box cover 3 Disengage the wiring connector and remove the voltage regulator 4 With the meter on Diode Check test between connector terminal pairs 5 9 7 9 10 9 11 9 12 9 10 5 5 11 5 12 and 5 3 It is important that the positive lead of the meter be con nected to the first terminal of each pair Re place the voltage regulator if any reading indi cates short or open except for pair 10 5 which should indicate open A good reading is approximately 0 5 which is the voltage drop across a diode Short is indi cated by zero or a number very nearly zero Me ters of different type may indicate open differ ently Read the meter instructions If in doubt compare readings with a regulator of the same part number known to be good 58 GENERATOR RECONNECTIONS When it is necessary to reconnect a generator re move the control panel and reconnect the leads at terminal block TB1 and
93. icing Brushes and Slip Rings 2x yes eeu Sete ey FIG ERN 51 Removing Remounting 52 Generator Assembly Disassembly 53 Testing the Generator 55 Testing For Field Voltage 58 Testing 1 Ph Voltage Regulators 58 Generator Becornnecllons oer ure 58 ENGINE BLOCK 5 62 G linder Heads z xad s erai uen Rec 62 Valve System ade La tene ando rdc M Fat eta Cd e ebd dew 63 CA COVEN PP DUERME 67 Governor Cup uode Ub uS REN Ke CIEN eae ud a 68 Timing Gears and oo m RO CORR dU EO ks aUe 69 Qi Pump ASSBITDIb ues se Su do eter or REP PN pH 70 Piston Assembly Ex E eR ER CD TAREAS 71 Grankshaft tcr rep Eu EE e CE Mi ei e eant addat an ads 75 76 OIL Seals lusit los E ERE Alger dna Doe d Da datos 77 Engine ei nir Poehler hee ee deb 78 SERVICE CHECKLIST os s aate e arc RO oe eec o B en rs oem 80 TROUBLESHOOTING bx eios 81 The Engine Does Not Crank oe eases aues 81 The Engine Cr
94. id is not opening the fuel solenoid or pump according to FUEL SYSTEM in Engine Sub pump is not pumping or the systems If the Fuel Pump indicator does not light during crank control is faulty Beginning ing replace the control board assembly Spec J 85 THE ENGINE CRANKS BUT DOES NOT START CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 11 The engine is not getting If you cannot hear or feel the solenoid open or the pump vibrate fuel because the fuel sole disconnect the lead to the fuel pump and or solenoid and and noid is not opening the fuel measure voltage at the end of the lead during cranking pump pus p 9t bs If there is at least 9 VDC test the fuel solenoid or pump ac control is faulty Spec cording to FUEL SYSTEM in Engine Subsystems Only If there is not at least 9 VDC see TESTING CONTROL BOARD 1 in Engine Control 12 The engine is not getting a Verify that the LPG fuel solenoid and gasoline fuel pump are con fuel because the fuel pump nected properly especially where the customer has mounted the and or fuel solenoid is not fuel pump remote from the genset and added a fuel tan
95. inadvertently opens the shutoff valve s at the LPG container s Large volumes of LPG can be released in the process of disconnecting a liquid withdrawal type of LPG supply sys tem Before disconnecting LPG fuel con nections make sure the the fuel shutoff valve s at the LPG container s are closed and that the vehicle is outside and away from pits or basements or other below grade spaces where LPG could accumu late For LPG vapor withdrawal gensets see Figure 32 on Page 38 disconnect the gas supply hose at the carburetor and the fuel solenoid shutoff valve leads at the control box on the genset If the pressure regulator solenoid valve assem bly is also to be removed cap the end of the fuel supply line with a threaded pipe cap to prevent fuel from escaping if someone inadvertently opens the shutoff valve s Removal of the Genset from the Vehicle See Figure 3 When the genset has been discon nected from the electrical exhaust and fuel sys tems examine its mounting bolts and support mem bers The genset drip tray is normally bolted to the vehicle framework Make sure that the genset is firmly supported before loosening any mounting BARRIER A MOUNTING HOLES bolts or support members A fork lift is recom mended to lift or move the genset Gensets are heavy and can cause severe personal injury if dropped during remov al Use adequate lifting devices Keep hands and feet clear while lifting COMPARTMENT
96. ing the heads clean out all carbon deposits Be careful not to damage the outer sealing edges where the gaskets fit The heads are made of aluminum and can be damaged by careless handling 3 It is a good idea to also remove the valves and clean carbon deposits from the valves and the intake and exhaust ports See VALVE SYS TEM 4 Use new head gaskets and clean both the heads and the cylinder block thoroughly where the gaskets rest 5 Place the heads in position and torque the head bolts in steps of 5 Ibs ft 7 N m in the numbered sequence shown in Figure 62 or 63 up to the specified torque of 15 17 Ibs ft 20 23 N m 62 6 Retorque the head bolts before the engine has run a total of 25 hours FIGURE 62 MODEL BGD CYLINDER HEAD BOLT TORQUE SEQUENCE LEFT SIDE RIGHT SIDE THE OIL FILTER SIDE IS THE RIGHT SIDE FIGURE 63 MODEL NHD CYLINDER HEAD BOLT TORQUE SEQUENCE VALVE SYSTEM See Figures 64 and 65 for the valve system layouts of the respective engines This engines have a side valve type of valve system layout A properly func VALVE STEM SEAL VALVE SPRING VALVE SEAT VALVE RETAINER INSERT GUIDE LOCK tioning valve system is essential for top engine
97. is not between 3 000 and 15 000 ohms Ignition Module Test 1 Remove both spark plugs and the cooling dis charge grill Figure 7 so that the engine can be turned by hand Connect the positive side of a voltmeter to the negative terminal of the ignition coil larger of the two screw terminals and the neg ative side of the voltmeter to engine ground Remove all leads from the positive terminal of the coil Use a jumper to connect the red lead of the igni tion module the one just removed from the coil to the battery positive terminal Rotate the flywheel clockwise by hand Re place the ignition module if voltage does not jump from approximately 1 volt to approximate ly 12 volts and then back again each revolu tion Ignition Coil Test 1 Remove all wires attached to the ignition coil 2 Remove the coil from the engine 3 Inspect the terminals for corrosion looseness cracks or other damage Look for carbon run ners around the high tension terminals these indicate electrical leakage Replace a dam aged or leaking coil 4 5 Clean the outside of the coil with a cloth damp ened in parts cleaning solvent Measure primary coil resistance across the positive and negative terminals Replace the ignition coil if primary resistance is not be tween 3 and 5 ohms Measure secondary coil resistance across the spark plug cable terminals Replace the i
98. ith the required clearance in cylinders machined to the matching oversize standard bore plus 0 005 0 010 0 020 0 030 and 0 040 inch There is no need to adjust or to fit pistons and rings Piston and ring size should be checked as described below to confirm that they are correct for the standard bore oversize Boring and honing must be accurate and remove just enough metal for the smallest oversize possible The finish hone should leave a 20 to 40 mi cro inch crosshatch finish having an included angle of 20 to 25 degrees The crosshatch finish is neces sary for fast piston ring break in See Figure 96 Clean the cylinder bore with hot soapy water anda brush after machining A clean white rag will not soil when the cylinder bore is clean Dry the bores and coat them with oil Do not use gasoline or commercial cleaning solvents to clean the cylinder bores af ter honing they do not remove abrasives FIGURE 96 PROPER HONE CROSSHATCH IN CYLINDER BORE Deglazing the Cylinder Bores Deglaze the cylinder bores for fast piston ring break in if the bores look good and there is not enough wear taper and out of roundness to warrant ma chining Deglazing should not increase the bore di ameter permitting the use of the original pistons if they good with new rings To deglaze the cylin der bores 1 Wipe the cylinder bores with a clean cloth that has been dipped in light engine oil 2 Use a brush ty
99. k shutoff installed properly solenoid The remote pump and solenoid must be connected to the genset using insulated conductors of at least 16 AWG have adequate bonding paths to the negative terminal of the battery and have corrosion free connections b Verify that the fuel pump gasoline gensets only is not more than 3 feet 9 M in elevation above the pickup tube in the fuel supply tank If it is relocate the fuel pump according to the instructions in the Installation Manual 13 The fuel mixture screws are Adjust as instructed in FUEL SYSTEM in Engine Subsystems not adjusted properly Prior to SPEC L only 14 The LPG demand regulator Test and adjust prior to SPEC L only and or replace as is malfunctioning instructed in FUEL SYSTEM in Engine Subsystems 15 The engine is worn or mal Do the CYLINDER COMPRESSION TEST in Engine Subsys functioning mechanically tems and service as necessary 86 THE ENGINE STOPS WHEN THE START SWITCH IS RELEASED BEGINNING SPEC J There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action Go to Step 1 if the engine stops when the Start switch is released but the starter disenga
100. kshaft until the TC mark on the fly wheel is lined up with the TC mark on the gear cover This should place the left piston at the top of its compression stroke Verify that the left intake and exhaust valves are closed and that there is no pressure on the valve lifters See Specifications for valve clearance When taking the clearance measurement the feeler gauge should just pass between the valve stem and valve tappet To correct the valve clearance turn the adjust ing screw as needed The screw is self locking To adjust the valves on the right cylinder turn the engine one complete revolution until the TC mark on the flywheel lines up again with the TC mark on the gear cover and then follow the same procedure as for the left cylinder Replace all parts removed Tighten all screws securely Torque the manifold bolts according to Assembly Torques EXHAUST SYSTEM See Figure 5 The exhaust system consists of the manifold muffler tailpipe and hardware for assem bling and mounting the components Exhaust gas is deadly The exhaust system must not leak and must discharge all en gine exhaust away from the vehicle Liability for injury death damage and warranty expense due to the use of an unapproved muf fler or due to modifications becomes the re sponsibility of the person installing the unap proved muffler or performing the modifications Use Onan approved exhaust system parts Muffler Replacemen
101. ligned with the notch in the rear opening of the crankcase and carefully slide the crankshaft out Inspection Inspect the rod and main bearing journals If they are worn or scored and cannot be smoothed by pol ishing either the journals should be reground to the next undersize or the crankshaft should be re placed Clean out the drilled oil passages in the crankshaft Installation 1 Lubricate the front and rear main bearings with engine oil 2 Use oil or gear lubricant to hold the front thrust washer in place against the engine block see Figure 90 The flat side of the thrust washer goes against the block 3 Position the crankshaft so that the crank throw is aligned with the notch at the rear of the crank case and install the crankshaft Make sure the front thrust washer did not slip out of place dur ing installation 4 Place the oil seal loader on the oil seal guide and driver and insert it into the rear bearing plate Remove the seal guide and driver leaving the loader in the bearing plate The loader pre vents the seal from being cut on the crankshaft keyway during installation of the rear bearing plate 5 Use oil or gear lubricant to hold the shim s and rear thrust washer in position on the rear bear ing plate see Figure 89 The shim goes against the bearing plate and the flat surface of the thrust washer goes against the shim 6 Place the bearing plate gasket in position on the block making sure
102. ly sys tem See Preparations Page 12 for the proper procedures and precautions 3 Remove the intake manifold capscrews the carburetor air preheater gasoline gensets only and the carburetor and intake manifold as an assembly On LPG gensets equipped for liquid withdrawal if will first be necessary to disconnect the fuel vaporizer the tube wrapped around the exhaust manifold at both ends remove the pressure regulator discon nect the vaporizer line from its support bracket and rotate the vaporizer line out of the way Bending the fuel vaporizer tub ing can weaken it to the point that it can crack allowing LPG under high pressure to escape resulting in possible severe per sonal injury or death 4 Remove the two intake manifold gaskets and cover the intake ports to prevent loose parts from accidentally entering the ports 5 Unbolt the carburetor from the intake manifold Reassembly Reassembly is the reverse of disas sembly Use new gaskets between the intake man ifold and the engine and between the intake man ifold and the carburetor Do not use sealer on the gaskets Tighten all fasteners according to Assem bly Torques O RING Slip the O ring over the end of the preheater hose and insert it into the collar AIR PREHEATER AND HOSE a gasoline gensets only CRANKCASE BREATHER HOSE AND CLIP AIR CLEANER AIR HOUSING FILTER ADAPTOR CARBURETOR A AIR ELEMENT GASKET CLEANER ADAPTOR
103. m battery ily rags improperly stored Safety glasses Explosion Flammable liquids improperly Hard hats stored Do not wear rings or jewelry and do not wear Hot exhaust pipes loose clothing that might get caught on equip Hot engine and generator sur ment e Electrical shorts e Reduce the hazard A safe orderly workshop area and well maintained equipment reduce Gas haust gases can accumulate the hazard potential Keep guards and shields in place on machinery and maintain equipment in good working condition Store flammable liq Improper generator connec tions eh Electrical e Faulty wiring uids in approved containers away from fire Shock AC Working in damp conditions flame spark pilot light switches arc produc e Jewelry touching electrical ing equipment and other ignition sources Keep components the workshop clean and well lighted and pro vide adequate ventilation Machinery e Develop safe work habits Unsafe actions cause accidents with tools and machines Be Surfaces familiar with the equipment and know how to use it safely Use the correct tool for the job and Objects Removing heavy components 10 SPECIAL TOOLS The tools listed below are necessary for servicing the genset See the Onan Tool Catalog Engine Tools Torque wrench 0 75 Ibs ft 0 100 N m Hole gauge 0 300 0 400 inch 5 10 mm Outside micrometer set 0 4 inch 0 100 mm Telescoping gauge set up to 4 inch 100 mm Feeler gaug
104. main bearing always align the oil hole s in the bearing with the oil hole s in the bearing bore The oil passage must be at least 1 2 open Rear Bearing Use the special driver available to drive in the rear main bearing Push the bearing into the bearing plate from the inner side to the depth al lowed by the flange on the driver See Figure 89 Front Bearing Use Loctite brand Bearing Mount or equivalent when installing the front bearing Use the towelette furnished with the bearing kit to clean the outside of the bearing and the bearing bore in the block Apply the Loctite to the mating surfaces of the bearing and bearing bore Allow three to four min utes for drying Breathing the vapor from the towe lette provided with the Loctite or prolonged contact with skin can be harmful Be sure the work area is well ventilated Use the special driver available to drive in the front bearing Push the bearing in to the depth allowed by the flange on the driver Wipe off any excess Loctite and allow one hour for hardening at room tempera ture See Figure 90 Engines shipped from the factory have separate thrust washers and main bearings for both front and rear of engine The front bearing replacement part is a one piece bearing with attached thrust washer as shown Do not add an additional thrust washer to this front bearing 76 REAR BEARING LOCK END PLATE PINS ALIGN BEARING OIL HOLES WITH OIL HOLES IN BEARING BORE My
105. mately 1 5 psi 10 3 kPa The secon dary stage is a demand regulator that delivers LPG vapor at the rate demanded by the carburetor The regulator should require little attention if the genset is operated regularly Most regulator mal function is due to e Hardened diaphragms and valve seats The pressure regulator in a genset that has been operated and then stored for a long time might require replacement because diaphragms gaskets and valve seats tend to shrink and harden over time e Fuel impurities and oils dissolved in the liquid LPG Impurities can form granules that become embedded in the secondary valve seat causing it to leak and oils can clog passages inside the regulator The results could be hard starting er ratic idling and poor load acceptance Testing the Demand Regulator Use compressed air and a pressure gauge to test the regulator as fol lows 1 Connect a pressure gauge to the test port on the back of the regulator 2 Connect a source of compressed air at least 80 psi 550 to the inlet opening and open the air pressure valve 3 If the primary valve is sound the gauge will indi cate approximately 1 5 psi 10 3 kPa and the pressure will remain constant Fluctuating pressure indicates a leaking primary valve seat 4 Close the air pressure valve and observe the pressure gauge The pressure should remain constant If the pressure drops the secondary valve seat is leaking 5 Disassemble
106. mount if after assembling the motor When mounting the solenoid make sure the plunger is hooked by the shift fork The drive housing motor frame and end bell are separable after the motor through bolts have been removed Before loosening the through bolts however scratch register lines on the drive housing motor frame and end bell so that these parts can be easily reassembled the same way relative to each other While removing the end bell be prepared to catch the brush springs which tend to spring loose ARMATURE END BELL BRUSH ASSEMBLY FIGURE 34 SOLENOID SHIFT STARTER BEGINNING SPEC J 41 Solenoid Refer to Figure 35 Before replacing the solenoid confirm that it is the cause of the starter not working by removing it from the starter assembly and con ducting the following tests 1 Connect 6 volt battery positive to solenoid terminal S and battery negative to solenoid terminal M The plunger should pull in and hold in strongly If it does not replace the solenoid 2 Connect 6 volt battery positive 4 to solenoid terminal S and battery negative to the body of the solenoid Push the plunger in and release it The plunger should stay in If it does not re place the solenoid 3 Connect 12 volt battery positive to solenoid terminal M and battery negative to the sole noid body reversed from normal polarity Push the plunger in and release it The plunger should push back out immedia
107. mpartment from the ve hicle interior Seal openings as necessary Make sure that all soundproofing material is in place Regular maintenance can prevent many of the problems listed below Removing and cleaning the cylinder heads every 500 hours is especially impor tant for gasoline models Before considering major engine service because of abnormal performance refer to Periodic Maintenance in the Operator s Manual for instructions on how to clean the cylinder heads using Onan 4 Troubleshooting These troubleshooting charts are designed to help you think through genset problems To save time troubleshooting read the entire manual ahead of time to understand the genset Try to think through problems Go over what was done during the last service call The problem could be as simple as an empty fuel tank closed fuel shutoff valve loose wire blown fuse or tripped circuit breaker THE ENGINE DOES NOT CRANK There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The remote enable switch if supplied is OFF Turn the key switch ON If necessary verify that the switch works and that the customer connected it a
108. n inspected and repaired Never sleep in the vehicle while the genset is running unless the vehicle has a working carbon mon oxide detector The exhaust system must be installed in accordance with the genset Installation Manual Make sure there is ample fresh air when operating the genset in a confined area CARBURETOR AND SPARK PLUG GOVERNOR ADJUSTMENTS HIDDEN BATTERY CABLE CONNECTIONS HIDDEN BLOWER HOUSING 0 PA E Ey S 24h COOLING SN SS AIR bl EL me LINE THE EXHAUST al Ex LIA CIRCUIT OUTLET Y BREAKERS FLANGE IS ACCESSIBLE THROUGH THE WARM AIR DISCHARGE AC OPENING VOLTAGE REGULATOR WARM 1 PHASE AIR DISCHARGE REMOTE START CONTROL ENABLE SWITCH REMOTE CONTROL CONTROL GASOLINE PANEL CONNECTOR CONNECTOR PLUG FUSE F1 FUEL PUMP FIGURE 2 TYPICAL GENSET Specifications GENERATOR 4 Pole Revolving Field Self Excited Electronically Regulated 4500 4000 6500 5000 Frequency Herz 120 240 Volt Single Phase Output Current amperes 1 0 PF 37 5 18 8 33 3 16 6 54 57 41 7 20 8 120 240 Volt Three Phase Output Current 220 380 Volt Three Phase Output Current 10 5 6 1 a 13 1 76 amperes 1 0 PF Speed RPM 1800 1500 1800 1500 FUEL CONSUMPTION No load gph l h Half load gph l h Full load gph l h ENGINE 2 Cylinder Opposed 4 Cycle Spark Ignited Side Valve Air Cooled 14 18 BTDC non adjus
109. nd or CB3 3 A main stator winding is Test and service according to TESTING THE GENERATOR in shorted or grounded Generator 4 A load has a ground fault or Service the faulty equipment as necessary short circuit 97 THE GENSET DOES NOT CHARGE THE BATTERY There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 Circuit breaker CB4 is faulty Check for continuity across the terminals Replace if resistance Spec H only is greater than zero ohms 2 PMG leads J8 1 and J8 2 Remove the control panel and verify that all generator connec beginning Spec J or Gen tions are according to the appropriate connection diagram in erator winding leads B1 and Generator B2 Spec H only battery charging voltage regulator VR2 and circuit breaker CB4 Spec only are not connected properly 3 Battery charging voltage Disconnect the lead at terminal B on voltage regulator VR2 and regulator VR2 is faulty measure voltage VDC while the genset is running If all wiring corrections are correct replace voltage regulator VR2 if output is less than 12 VDC 98 WIRING DIAGRAM SCHEMATIC Wiring Diagrams
110. ng B1 B2 is faulty Isolate the B1 B2 winding lead pair orange striped leads by dis connecting connectors J7 and J8 inside the control box and the two leads at the AC terminals on battery charging voltage regula tor VR2 mounted on a bracket on the generator and test the winding as instructed under TESTING THE GENERATOR in Generator If the B1 B2 winding is faulty replace the entire stator assembly 5 Control Board A1 is faulty Check the control board connector according to TESTING CON TROL BOARD A1 in Engine Control and replace control board A1 if cleaning the connector does not help No Low Output Voltage 6 Field voltage is low Measure field voltage while cranking the engine See TESTING FOR FIELD VOLTAGE in Generator If there is at least 9 VDC across the brush block terminals test and service or replace the brushes slip rings rotor and stator according to SERVICING THE BRUSHES AND SLIP RINGS and TESTING THE GEN ERATOR in Generator 7 Control Board 1 is faulty Measure voltage between output voltage regulator VR1 connec tor pin 7 connector J9 on 3 phase gensets and ground while cranking the engine If there is less than 9 VDC check the control board connector according to TESTING CONTROL BOARD A1 in Engine Control and replace engine control board A1 if cleaning the connector does not help 89 THE ENGINE STOPS WHEN THE START SWITCH IS RELEASED SPEC H ONLY CONTINUED There are hazards present in troubles
111. ntrol box 4 Remove the three stator clamps 5 Lift the stator straight up and out of the housing Careless handling of the stator can damage the insulation on the stator windings FIGURE 51 REMOVING THE STATOR Re installing the Stator in the Generator Re installing the stator is the reverse of removal Make sure the stator leads line up with the exit hole in the housing while lowering the stator into the housing Connect the leads according to the ap propriate connection diagram in Figure 59 60 or 61 Removing and Replacing the Rotor Bearing Use a gear puller to remove the bearing from the ro tor shaft if it or the slip ring assembly is to be re placed otherwise leave it in place See Figure 52 If the bearing is to be reused make sure the fingers of the gear puller bear on the inner race of the bearing only The bearing will be damaged and become unusable if force is applied to the outer race either when pulling it off or pressing it on Replace the bearing as follows 1 Replace the slip ring assembly first if neces sary 2 Press the bearing on with a press making sure to bear down on the inner race only FIGURE 52 BEARING REMOVAL Removing and Replacing the Slip Ring Assembly Unsolder the two rotor leads from the slip ring as sembly and pull the slip ring assembly off with a gear puller Tape the key to the shaft to keep from loosing it if a new assembly is not going to be installed right aw
112. o FUEL SYS TEM in Engine Subsystems b Check for and repair a vacuum leak c Overhaul prior to Spec L only or replace the carburetor accord ing to FUEL SYSTEM in Engine Subsystems 90 THE ENGINE MISFIRES OR BACKFIRES CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 3 The fuel gasoline is con Connect the genset to a container of fuel of known quality and run taminated the genset under various loads Replace the contents of the fuel supply tank if there is a noticeable improvement in performance 4 The engine is malfunction Service as necessary according to Engine Block Assembly ing mechanically THE ENGINE LACKS POWER There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 There is carbon build up in Remove the heads and clean using Onan 4 according the Op the cylinder h
113. oil pressure is Bypass low oil pressure cutout switch S2 by disconnecting con low or the cutout switch is trol board A1 connector lead J1 5 J5 from connector J5 and faulty grounding it and start the genset If bypassing switch S2 allows the engine to continue running remove the pressure switch for access remove the cylinder shroud on the oil filter side install an oil pressure gauge and run the genset If oil pressure is at least 12 psi replace low oil pressure cut out switch 52 If oil pressure is less than 12 psi service the engine accord ing to LUBRICATION SYSTEM in Engine Block Assembly 3 Stop Relay 5 is faulty Disconnect stop relay K5 by disconnecting engine control board 1 connector lead J1 10 CR6 from CR6 inside the control box and start the genset If disconnecting relay K5 allows the engine to continue running check wiring in the stop relay K5 circuit against the appropriate wiring diagram in Wiring Diagrams If the wiring is good replace relay K5 88 THE ENGINE STOPS WHEN THE START SWITCH IS RELEASED SPEC H ONLY CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 4 Windi
114. olt The other end of the rotor is supported in a sealed pre lubricated ball bearing assembly The cooling blower wheel and starter ring gear are part of the rotor assembly See Figure 44 GENERATOR HOUSING BRUSH BLOCK ASSEMBLY SINGLE PHASE VOLTAGE ADJUSTING POTENTIOMETER LINE CIRCUIT BREAKERS CB1 CB2 CB3 TERMINAL BOARD TB1 SPEC H 1 PH VOLTAGE REGULATOR SPEC J 1 PH VOLTAGE REGULATOR IS MOUNTED ON THE DRIP PAN FIGURE 2 SPEC J 1 PH 50 HZ HAS AN ISOLATION TRANSFORMER FOR VOLTAGE REFERENCE MOUNTED AT THIS LOCATION FIGURE 44 GENERATOR COMPONENTS 49 BASIC GENERATOR OPERATION Refer to Figure 45 and to Wiring Diagrams while wo rking through the following description of opera tion 1 Voltage regulator VR1 supplies DC power to the main rotor field windings through the brushes and slip rings A rotating four pole magnetic field is thereby established that in duces AC in the stator windings Quadrature windings are provided for single phase genera tors to power the voltage regulator The main windings provide power for the voltage regula tor on three phase generators While the governor matches engine output to the load maintaining a constant speed fre iml AC OUTPUT VOLTAGE quency the voltage regulator senses output voltage and adjusts field current to maintain a constant output voltage 3 During startup the voltage regulator is pow ered by the battery for fas
115. on its side of the insulating divide Fig ure 47 5 Remount the brush block Center the brushes on the slip rings before tightening the mounting screws Reconnect the lead marked F1 to the outboard brush terminal and the lead marked F2 to the in board brush terminal and secure the cover and air cleaner 1 IN 25 mm FIGURE 46 CHECKING BRUSH WEAR BRUSH PIG TAILS FEAD BRUSH TERMINALS 29 SPRING FIGURE 47 BRUSH BLOCK ASSEMBLY 51 REMOVING REMOUNTING GENERATOR Removing the Generator from the Genset 1 52 Drain the engine oil while the genset is mounted in the vehicle Oil will spill out when the genset is tipped up on end to remove the generator unless the oil has been drained Remove the genset from the vehicle and place it on a sturdy work bench See Preparing for Service Remove the blower housing so that the genset can be rested flat on the blower wheel See EN GINE COOLING SYSTEM in Engine Subsys tems for instructions Disconnect the fuel line at the carburetor Disconnect the leads at the low oil pressure cut off switch and B terminal of the ignition coil Use a 3 8 inch allen wrench and rubber mallet to remove the rotor through bolt Thread a 9 16 12 eyebolt into the end of the ro tor and tip the genset up with a hoist until it rests squarely on the blower wheel See Figure 48 Do not lift the genset with the eyebolt The weight of the genset could cau
116. pe deglazing tool with coated bristle tips 3 Drive the tool with a slow speed drill Move the tool up and down in the cylinder bores fast enough to obtain the crosshatch pattern shown Figure 96 Ten to twelve strokes should be sufficient 4 Clean the cylinder bore with hot soapy water and a brush after deglazing A clean white rag will not soil when the cylinder bore is clean Dry the bores and coat them with oil 79 Service Checklist After servicing inspect and test the installation to confirm that the genset will operate as intended Check each of the areas described below before putting the genset into service Mounting Examine all mounting bolts and supporting mem bers to verify that the genset is properly mounted All fasteners should be tightened securely to pre vent them from working loose when subjected to vibration Lubrication If the engine oil was drained refill as instructed in the Operator s Manual Wiring Verify that all wiring connections are tight and installed properly Check each of these connec tions e Load wires Control wires e Ground straps e Battery cables Initial Start Adjustments Perform governor and carburetor adjustments ac cording to Engine Subsystems if they have not been done already Output Check Apply a full load to make sure the genset can pro duce its full rated output Use a load test panel to ap ply a progressively greater load until full load is rea
117. r pin Lock the cup in place with the snap ring Camshaft Center Pin Installation 1 68 The camshaft center pin extends 3 4 inch 19 mm from the end of the camshaft This dis tance provides 7 32 inch 5 5 mm travel for the governor cup as shown Measure this distance 2 while holding the cup against the flyballs If the distance is less the engine may race especial ly at no load Remove the center pin and press in a new pin the specified amount Do not hammer the new pin into place or it will be damaged The cam shaft center pin cannot be pulled outward or re moved without damage If the center pin ex tends too far the cup will not hold the flyballs properly 3 4 in 19 mm 7 32 in 5 5 mm SNAP RING GOVERNOR CUP GOVERNOR FLYBALL CAMSHAFT WHEN THE GOVERNOR 1 PROPERLY ASSEMBLED THE DIMENSIONS SHOWN ON DRAWING WILL BE AS INDICATED FIGURE 73 GOVERNOR CUP TIMING GEARS AND CAMSHAFT the timing gear and the block and that the 0 marks on the timing gears line up as shown in If either timing gear needs replacement both gears Figure 74 should be replaced Also the camshaft and its gear are replaceable only as an assembly See Fig 5 Install the oil pump assembly ure 74 6 Install the retainer washer and snap ring in front of the crankshaft timing gear Removal 1 Remove the valve tappets so that the camshaft GEAR CRANKSHAFT can be withdrawn PULLER 2 Remove the sn
118. re 15 It controls oil pressure by allowing excess oil to flow back to the crankcase It is non adjustable and normally needs no mainte nance If it is suspected that it is the cause of high or low oil pressure inspect it as follows 1 Remove the 3 8 capscrew behind the gear cov er and under the governor arm 2 3 4 Remove the spring and plunger with magnet ic tool and clean them Replace the plunger if its diameter is not 0 3105 to 0 3125 inch 7 89 to 7 94 mm Replace the spring if its free length is not approximately 1 inch 25 4 mm or if it takes other than 2 4 2 8 pounds 10 7 12 5 N to compress it 0 5 inch 12 7 mm Check the bore and valve seat and clean away any debris GASKET ADAPTER LOW OIL PRESSURE CUTOUT SWITCH DRIP SHIELD FLAT WASHER HEX CAP SPRING FIGURE 15 OIL BYPASS VALVE 23 FUEL SYSTEM The carburetor mixes air and fuel in the correct pro portion for good performance The governor oper ates the throttle to maintain a nearly constant en gine speed frequency as the load varies Figure 16 is representative of most of the fuel system parts LPG liquified petroleum gas systems do not use an air preheater or choke and have different fuel connections See Automatic Choke Fuel Pump and LPG System Components in this section for details of the other parts of the fuel system Gasoline and LPG are flammable and explosive and can cause severe personal inj
119. rformed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The fuel mixture is too lean Adjust according to Governor and Carburetor Adjustments under FUEL SYSTEM in Engine Subsystems prior to Spec L only 2 The engine cooling fins are Clean as necessary oily and dirty 3 The installation restricts Verify that the installation is in accordance with the Installation cooling air Manual THE ENGINE HAS HIGH OIL CONSUMPTION There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The oil is diluted or has too Replace the oil in the crankcase with oil of correct viscosity See light a viscosity the Operator s Manual for engine oil recommendations 2 The crankcase breather Service or replace the breather valve according to CRANKCASE valve is dirty or defective BREATHER ASSEMBLY in Engine Subsystems 4 The oil bypass valve is Service as necessary according to LUBRICATION SYSTEM in faulty Engine Block Assembly 5 The engine is worn or mal Do the
120. rks pilot lights electri cal arc producing equipment and switches and all other sources of ignition well away from areas where fuel fumes are present and areas sharing ventilation e Fuel lines must be secured free of leaks and sepa rated or shielded from electrical wiring e Use approved non conductive flexible fuel hose for fuel connections at the genset ENGINE EXHAUST IS DEADLY e Learn the symptoms of carbon monoxide poisoning in this Manual Never sleep in the vehicle while the genset is run ning unless the vehicle has a working carbon mon oxide detector e The exhaust system must be installed in accor dance with the genset Installation Manual e Do not use engine cooling air to heat the vehicle in terior e Make sure there is ample fresh air when operating the genset in a confined area MOVING PARTS CAN CAUSE SEVERE PERSONAL INJURY OR DEATH Do not wear loose clothing or jewelry near moving parts such as PTO shafts fans belts and pulleys e Keep hands away from moving parts e Keep guards in place over fans belts pulleys etc BATTERY GAS IS EXPLOSIVE e WEAR SAFETY GLASSES and DO NOT SMOKE while servicing batteries e When disconnecting or reconnecting battery cables always disconnect the negative battery cable first and reconnect it last to reduce arcing Table of Contents SAFETY PRECAUTIONS Inside Front Cover INTRODUCTION Gree eo ed
121. rom the valve face and seat Deeply pitted or cut valves must be replaced because grinding re moves the margin Grind or cut the valve seats at 45 degrees The seat band should be 1 32 3 64 inch 0 79 1 2 mm wide Remove only enough material to ensure proper valve seating If a valve seat is cracked or loose or does not have enough material left to seat the valve properly replace the entire block assembly Check each valve for a tight seat Make several marks at regular intervals across the valve face us ing machinist s bluing The marks should rub off uni formly when the valve is rotated a quarter turn against the seat indicating even contact all the way around The line of contact should be at the center of the valve face VALVE HEAD INTERFERENCE ANGLE FIGURE 69 VALVE INTERFERENCE ANGLE WARPED VALVE KNIFE EDGE Uy GOOD MARGIN EN t Wi 0 30 MINI FIGURE 70 VALVE MARGIN 65 Replacing the Valve Guides Worn valve stem guides can be replaced from in side the valve chamber The smaller diameter of the tapered valve guides must face toward the valve head Removal 1 Before removing the valve guides use an elec tric drill with a wire brush to remove carbon and other foreign material from the top surface of the guides Failure to do this may result in dam age to the guide bores Drive the guides out with a hammer and a valve guide driver Driving out the old valve guides c
122. rough AC voltage regula tor VR1 for fast build up of generator output voltage 2 Low oil pressure cutout switch S2 should close as soon as the engine starts up It must be closed before run relay K3 can be energized and must stay closed to keep the engine run ning 3 Start disconnect relay K2 on control board A1 pulls in as soon as generator voltage builds up It causes start relay K4 to drop out disconnects the field from the battery and causes run relay K3 to pull in When K4 drops out it cause K1 to drop out disconnecting the starter When K3 pulls in it keeps the fuel and ignition circuits ac tive so that the genset will continue to run 4 The genset will continue to run when Start Stop switch 1 is released and returns to its center run position If the switch is held in after the genset has started relay K2 will still cause the starter to be disconnected 5 Momentarily pushing Start Stop switch S1 to Stop causes run relay K3 to drop out causing the ignition and fuel circuits to deactivate shut ting down the genset Relay K5 also drops out closing its contacts to keep relay K3 out pre venting the genset from restarting if it has not stopped before S1 is released 47 Testing Control Board A1 Spec H Only Confirm that control board A1 Figure 43 is faulty before replacing it Use a DC voltmeter and an ohm meter to perform the following tests 1 Disconnect the negative battery cable 2
123. s service or product information be ready to provide the model number and the serial number both of which appear on the genset nameplate See Table 1 for the significance of each character of the model number and Figure 1 for how the model and serial numbers are displayed on the nameplate Introduction TABLE 1 MODEL NUMBER B 30502 4 5 Rated Power in Kilowatts Genset Family Starting Method Code Voltage and Frequency Code Options and Special Features Code Spec Letter designating modifications IMPORTANT ENGINE INFORMATION Onon ONAN CORPORATION 1400 73rd Ave NE 6 5NHDFB30502L Minneapolis MN 55432 953123456 Made in U S A AC Volts Amps Fuel Insulation NEMA Class Ambient 40 C INI 3461 URC SPECIFICATIONS AND ADJUSTMENTS THIS ENGINE MEETS 1995 1998 CALIFORNIA EMISSIONS REGULATIONS FOR ULGE ENGINES EM SN5980U1G2RA 980 cc FIGURE 1 TYPICAL NAMEPLATE EXHAUST GAS IS DEADLY All engine exhaust contains contain carbon monoxide an odorless colorless poisonous gas that can cause unconsciousness and death Symptoms of carbon monoxide poisoning include e Dizziness e Nausea e Headache e Vomiting e Weakness and Sleepiness e Inability to Think Coherently IF YOU EXPERIENCE ANY OF THESE SYMPTOMS GET INTO FRESH AIR IMMEDIATELY If symp toms persist seek medical attention Shut down the genset and do not operate it until it has bee
124. se the tapered crankshaft rotor fit to break loose leading to generator damage Disconnect the ground strap from the drip tray remove the four vibration isolator center bolts for reassembly note the locations of the large flat washers and pull the tray away Remove the four bolts nuts and lock washers that secure the generator housing to the gen set 10 Remove the eyebolt and insert the rotor remov al rod headless bolt Figure 49 and thread it in with a screwdriver until it bottoms Thread in and tighten a 9 16 12x1 3 4 bolt against the rod until the rotor breaks loose from the crankshaft EYEBOLT 9 16 12 FIGURE 49 ROTOR REMOVAL TOOL Remounting the Generator on the Genset Essentially remounting is the reverse of removal Note the following 1 First reassemble the generator housing stator and rotor as instructed if they have been taken apart 2 It is recommended that the rotor removal tool be threaded into the crankshaft to guide the ro tor into the crankshaft as the assembly is low ered using an eyebolt Figure 48 and hoist 3 The lock washers go under the bolt heads of the generator mounting bolts 4 Locate the large flat washers at the locations noted when disassembling the vibration isola tors Step 8 under Removal 5 Torque the generator housing rotor through bolt and vibration isolator center bolts to As sembly Torques 6 Make sure to secure the ground strap to th
125. ssary according to SERVICING THE BRUSHES good contact with the slip AND SLIP RINGS in Generator rings 4 The generator is connected Remove the control panel and verify that all generator connec wrong tions are according to the appropriate connection diagram in Generator 5 The rotor winding is shorted Test and service according to TESTING THE GENERATOR in Generator 6 A main stator winding is Test and service according to TESTING THE GENERATOR in shorted or grounded Generator 7 Voltage regulator VR1 is Test and service according to TESTING THE VOLTAGE REG faulty ULATOR in Generator 95 THE GENERATOR IS NOISY There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The brush block is loose Tighten the mounting screws as necessary 2 The generator bearing is Replace according to ASSEMBLING AND DISASSEMBLING worn THE GENERATOR in Generator 3 The rotor and crankshaft are Service according to ASSEMBLING AND DISASSEMBLING misaligned THE GENERATOR in Generator THE GENERATOR OVERHEATS There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting m
126. stator windings are crimped to the motor frame grounded To check the integrity of each winding pair use an ohmmeter to check for continuity be tween its brush and the motor frame Replace the motor frame if either winding pair is open high re sistance This test will not detect if a single winding of a pair is open If the windings look burnt or smell bad it is recommended that the motor frame be re placed Pinion Refer to Figure 40 Replace the pinion assembly if the pinion teeth and armature shaft splines are worn or damaged Check the over running clutch by ro tating the pinion clockwise and counterclockwise Replace the pinion assembly if it does not turn smoothly counterclockwise or lock clockwise Do not clean the pinion overrunning clutch with any kind of cleaning solution other wise it may be damaged MICA UNDERCUT SAW BLADE pr ati FIGURE 38 COMMUTATOR MICA UNDERCUT FIGURE 39 CHECKING MOTOR FRAME WINDINGS FIGURE 40 CHECKING OPERATION OF THE PIN ION OVER RUNNING CLUTCH 43 Engine Control The engine control system provides a means to start run and stop the engine automatically disen gage the starter recharge the battery automatically shut down the genset in the event of low oil pressure and start stop and monitor the genset from the cab or other location CONTROL SYSTEM BEGINNING SPEC J See Wiring Diagrams for the appropriate schematic and connection diagrams
127. supply system Gensets equipped for vapor withdrawal of LPG must be equipped with a fuel shutoff solenoid valve and de SOLENOID PIGTAIL CONNECTIONS AT THE GENSET v z 4 ur llr 1 11 VENT PRESSURE BALANCE HOSE Must extend outside the genset compartment to prevent accumulation of LPG in compartment in the event the diaphragm leaks and to prevent erratic fuel delivery because of pressure fluctuations cause by the cooling air flow through the compartment GAS SUPPLY HOSE TO THE CARBURETOR INLET mand regulator These are available as a kit for mounting near the genset See Figure 32 LPG is flammable and explosive and can cause asphyxiation NFPA 58 Section 1 6 requires all persons handling LPG to be trained in proper handling and operating proce dures MOUNTING BRACKET FUEL SHUTOFF SOLENOID VALVE DEMAND REGULATOR The regulator must be mounted such that the diaphragm is in a vertical plane as shown to maintain calibrated gas pressure FIGURE 32 LPG SYSTEM COMPONENTS FOR VAPOR WITHDRAWAL 38 LPG Supply Pressure LPG supply pressure must be maintained at 9 13 inches 229 330 mm water column WC under all conditions Adjust the supply pressure as follows 1 Close the gas shutoff valve s at the LPG con tainer s 2 Remove the 1 8 inch pipe plug from the regula tor test port Figure 33 and connect a manom eter calibrated in inches or mm WC having a scale rang
128. systems to cause the genset to shut down Troubleshooting The indicator lights on the control panel should be used in conjunction with Troubleshooting to narrow the search for the problem If for example the Fuel Pump or Ignition light is on but it has been deter mined that there is no fuel or no ignition spark the problem is not in the control board but in the rest of the circuit 45 CONTROL SYSTEM SPEC H ONLY See Figure 42 and Wiring Diagrams The control system consists of the following components Printed Circuit Board A1 The printed circuit board includes the relays K2 and K4 switch S1 and circuits necessary to start run and stop the genset automatically disconnect the starter shut down the genset in the event of low oil pressure and connect to a remote control circuit It is mounted on the back of the control panel Start Stop Switch S1 This is a rocker switch mounted on the printed circuit board to start and stop the genset The switch returns to the center BATTERY CHARGING VOLTAGE RELAYS REGULATOR VR2 r l iaa a r A LENOID CIRCUIT BREAKER CB4 LOCATED INSIDE BOX NOT SHOWN CONTROL BOARD 1 WITH FUSE F1 AND START STOP SWITCH S1 VR2 K5 K6 AND CB4 ARE MOUNTED ON THE OUT PUT VOLTAGE REGULATOR VR1 BRACKET ON 3 PHASE GENSETS K5 AND K6 run position when released It is not separately re placeable
129. t bearing A copper colored crossover tube carries oil to the rear main bearing The connecting rod jour nals are lubricated through drilled passages from the main journals The oil overflow from the bypass valve lubricates the camshaft drive gears Replace the oil pump if the crossover tube is tight and the oil bypass valve is functioning properly but the oil pressure is below specification The gasket and pick up cup are the only individually replace able parts Oil the pump generously when reassem bling it so that it will prime faster when the engine is first started 70 OIL PICKUP SCREEN OIL PUMP FIGURE 75 OIL PUMP ASSEMBLY PISTON ASSEMBLY The piston assembly consists of the piston rings and connecting rod assembly After removal from the engine all parts must be carefully inspected for damage and wear before they are replaced Removal and Disassembly 1 Remove the ridge at the top of the cylinder with a ridge reamer before attempting to remove the piston Figure 76 Improper use of a ridge reamer can damage the cylinder bore Use this tool with extreme care 2 Turn the crankshaft until a piston is at the bot tom of its stroke 3 Remove the bearing caps from the connecting rods and push the rods and pistons out the top of the cylinders Be careful not to scratch the crankpin or the cylinder wall when removing these parts 4 Mark each piston rod and bearing cap so that they can be reassembled togeth
130. t for burned brushes and grooved or pitted slip rings and any other damage Turn the ro tor with a 3 8 inch allen wrench to be able to inspect all the way around the slip rings If everything looks good check brush wear with piece of wire marked off as shown in Figure 46 Re place the brushes and brush springs if the wire can be inserted more than 1 inch 25 mm into the hole in the brush holder Make sure the wire rests on top of the brush and not on part of the brush spring If the slip rings are grooved or pitted it might be pos sible to clean them up with a commutator stone If the slip rings are worn and need to be replaced see Removing and Replacing the Slip Ring Assembly under GENERATOR ASSEMBLY DISASSEMBLY in this section To replace the brushes or to clean up the slip rings 1 Disconnect the leads marked F1 and F2 from the brush block terminals 2 Remove the brush block mounting screws and lift out the brush block assembly 3 If the slip rings need to be cleaned up insulate the ends of leads F1 and F2 disconnect all leads from the positive terminal of the igni tion coil to keep the engine from starting hold the commutator stone lightly against the slip rings and crank the engine for 3 to 6 seconds Check the slip rings and repeat the procedure as necessary until the pits and groves have been removed 4 Replace the brushes and brush springs with new parts Connect each brush pigtail to the terminal
131. t generator voltage buildup Control board A1 disconnects the volt age regulator from the battery at the same time that it disconnects the starter See Engine Con trol 4 Beginning Spec J a PMG on the other end of the engine crankshaft from the generator sup plies power for charging the battery through voltage regulator VR2 Spec H gensets have separate generator stator windings for charg ing the battery through voltage regulator VR2 The battery charging output signal is also used for start disconnect See Engine Control OUTPUT VOLTAGE SIGNAL AC POWER OUTPUT REGULATOR VR1 AC POWER FOR REGULATOR 3 PH AC POWER FOR REGULATOR 1 PH A DC FIELD POWER ROTATING MAIN STATOR G1 MECHANICAL POWER INPUT 2 ae ep lt J LL 1 LL OF ENGINE MAIN ROTOR FIELD 2 2 lt or 2 or 2 a 2 LLI tr or gt BRUSHES AND SLIP RINGS START DISCONNECT B1 B2 WINDINGS SIGNAL 50 BATTERY CHARGING CURRENT CHARGING VOLTAGE REGULATOR VR2 BEGINNING SPEC J SPEC H ONLY BEGINNING SPEC J 1 PH 50 HZ AND 3 PH USE VOLTAGE REFERENCE TRANSFORMER T2 FIGURE 45 SCHEMATIC OF GENERATOR OPERATION SERVICING BRUSHES AND SLIP RINGS Remove the air cleaner and the brush block cover and inspec
132. t leads F1 and F2 from the brush running the genset block terminals Replace the stator assembly if any winding does not 3 Connect brush block terminal B inboard to meet the output specification in Table 5 or 6 as ap the negative battery terminal on the genset propriate TABLE 5 SINGLE PHASE GENERATOR STATOR SPECIFICATIONS WINDING RESISTANCES OHMS LEAD PAIR FREQUENCY LEAD PAIRS LEAD PAIR Q1 Q2 Hz 1 2 T3 T4 1 2 SPEC ONLY 0 327 0 058 2 089 LEAD PAIR FREQUENCY LEAD PAIRS LEAD PAIR Q1 Q2 Hz 1 2 T3 T4 B1 B2 SPEC H ONLY 20 These values are approximate plus or minus 10 percent at 68 F 20 C TABLE 6 THREE PHASE GENERATOR STATOR SPECIFICATIONS WINDING RESISTANCES OHMS LEAD PAIRS FREQUENCY T1 T4 T2 T5 T3 T6 LEAD PAIR a ROTOR T7 T10 T8 T11 WINDING iis SPEC H ONLY 1 625 0 716 LEAD PAIRS 1 4 T2 T5 T3 T6 Q1 Q2 eee SPEC H ONLY These values are approximate plus or minus 10 percent at 68 F 20 120 240 DELTA 57 TESTING FOR FIELD VOLTAGE To check the field voltage remove the brush block cover and connect a DC voltmeter to the brush block terminals See Figure 57 Connect the positive lead to the B outboard terminal and the negative lead to the B inboard terminal Start the genset and allow it to stabilize Measure the field voltage with no load applied and then with full load applied Both readings s
133. t mufflers are available as kits that in clude all necessary hardware and gaskets Follow the instructions in the kits exactly FLANGE AT EXIT OF EXHAUST MANIFOLD FLANGE GASKET FLANGE TO MUFFLER CONNECTOR AND CLAMP To remove the muffler remove the tail pipe the muf fler support strap screws and the inlet flange bolts and pull the muffler away Always reassemble with new muffler flange gas kets Tailpipe The tailpipe is not supplied by Onan If it is neces sary to replace the tailpipe use 1 3 8 inch 1 0 18 rigid steel tubing and 1 3 8 inch U bolt muffler clamps and shock mount hangers Important safety warnings and information and instructions regard ing the routing and termination of the tailpipe are in cluded in the Installation Manual The tailpipe must be mounted in such a way that it is protected from damage or dislocation and be terminated in such a way that exhaust gases will not recirculate back into the vehicle TAILPIPE AND HANGER SUPPLIED BY OTHERS MUFFLER FIGURE 5 TYPICAL MUFFLER INSTALLATION 15 Exhaust Manifold See Figure 6 To remove the exhaust manifold it will first be necessary to remove the muffler and then re move the genset from the vehicle See Prepara tions 1 16 Remove the cooling system noise shield fan guard and scroll Figure 7 to provide access to the exhaust manifold Remove the screw that secures the exhaust manifold outlet flange to the support bra
134. table 14 18 BTDC non adjustable 12 volt Minimum Battery Cold Cranking Capacity Above Below Freezing 360 450 amperes 360 450 amperes Nominal Regulated Voltage Battery Charging Output 10 amperes 10 amperes 10 amperes mini bayone GENERATOR 4 Pole Revolving Field Self Excited Electronically Regulated Power watts 4500 4000 6300 5000 Frequency Hart o o gt 120 240 Volt Single Phase Output Current amperes 1 0 PF 37 5 18 8 33 3 16 6 52 5 26 3 41 7 20 8 120 240 Volt Three Phase Output Current amperes 1 0 PF amos 220 380 Volt Three Phase Output Current amperes 1 0 PF Speed RPM 1800 1500 1800 1500 FUEL CONSUMPTION No load Ibs h kg h Half load Ibs h kg h Full load Ibs h kg h ENGINE 2 Cylinder Opposed 4 Cycle Spark Ignited Side Valve Air Cooled 14 18 BTDC non adjustable 14 18 BTDC non adjustable LPG Vapor Supply Pressure Range 9 to 13 inch 229 to 330 mm 9 to 13 inch 229 to 330 mm Vapor Withdrawal Only W C water column W C water column LPG Connection for Vapor Withdrawal 3 4 inch NPT Tapping 3 4 inch NPT Tapping LPG Connection for Liquid Withdrawal 1 4 inch NPTF Tapping 1 4 inch NPTF Tapping Exhaust Requirements 1 3 8 inch ID 18 Ga Steel Tubing 1 3 8 inch ID 18 Ga Steel Tubing CONTROL AND CRANKING SYSTEM 12 VDC Nominal Battery Voltage 12 volts 12 volts Minimum Battery Cold Cranking Capacity Above B
135. tall the other piston assembly and crank the engine by hand to see that all bearings are free Connecting Rod Bearing Clearance 1 2 74 Wipe all parts clean of oil and grease Select Plasti gage that corresponds to the con necting rod bearing clearance specification 0 0020 0 0033 inch 0 051 0 084 mm Place the piece of Plasti gage across the full width of the bearing cap about 1 4 inch 6 mm off cen ter Figure 87 Install the rod bearing caps as instructed in Step 6 of Piston Installation above Make sure not rotate the crankshaft or the Plasti gage will smear Remove the bearing cap leaving the Plasti gage on the part it sticks to Check the widest part of the flattened Plasti gage with the gradu ations on the envelope to determine the bear ing clearance FIGURE 85 INSERTING PISTON Torque the cap bolts to 5 lbs ft 7 N m remove any misalignment by striking the cap rod joint using a hardwood block and a leather or plastic mallet and then torque the cap bolts to specification FIGURE 87 USING PLASTI GAGE CRANKSHAFT Removal 1 Remove the piston rod assemblies if they have not already been removed 2 Remove the gear cover and crankshaft timing gear See GEAR COVER and TIMING GEARS in this section 3 Loosen the rear bearing plate screws and re move the bearing plate gasket thrust washer and shims See BEARINGS in this section 4 Turn the crankshaft so the crankthrow is a
136. tely If it does not replace the solenoid Armature Winding Integrity Refer to Figure 36 Use an ohm meter to check for electrical continuity between pairs of commutator segments all the way around the commutator Make sure each segment is checked Replace the armature if a winding is open high resistance at any segment Winding Insulation Refer to Figure 37 Use an ohmmeter to check for winding insulation break down between the windings and the rotor lamina tions Replace the armature if the ohmmeter does not indicate high resistance on its highest scale be tween any commutator segment and the rotor lami nations 42 FIGURE 37 CHECKING WINDING INSULATION Commutator Clean the commutator surface with sandpaper Measure the diameter at several loca tions around the commutator Turn the commutator in a lathe if it is not round or has deep pits Replace the armature if it is necessary to turn the diameter of the commutator to less than 1 1 16 inch 27 mm Using a hacksaw blade undercut the mica between the commutator segments by 1 32 inch and chamfer the edges of the segments slightly See Figure 38 Brush Assembly Replace the motor frame and brush assembly if any brush is less than 0 43 inch 11 mm long Motor Frame and Stator Refer to Figure 39 Two of the four brushes are con nected directly to the stator windings one to each pair of windings The other ends of the two pairs of
137. that include new gaskets and float assembly parts Disassembly Carefully note how the carburetor parts fit together as the carburetor is being disas sembled so that it will be easier to reassemble Read and understand these instructions before starting 1 Remove the air cleaner adapter and the auto matic choke assembly gasoline carburetors 2 Remove the throttle and choke plate retaining screws then remove the plates Pull out the throttle and choke shafts being careful not to damage the Teflon coating applied to the shafts 3 Remove the main and idle mixture screw as semblies 4 Separate the lower section of the carburetor float bowl from the body of the carburetor 5 Carefully note the position of the float assembly parts then remove the hinge pin float and needle valve gasoline carburetors Cleaning and Repair 1 Soak all metal components not replaced by the repair kit in carburetor cleaner Do not soak any rubber or plastic parts Follow the cleaner manufacturer s recommendations Most parts cleaning solvents are flammable and corrosive and can cause severe burns and inflammation Use only as recommended by the manufacturer 2 Clean all carbon from the carburetor bore es pecially where the throttle and choke plates seat Be careful not to plug the idle or main fuel ports 3 Blow out all passages with compressed air Do not use wire or other objects for cleaning that might increase the siz
138. the battery charging circuit according to THE GENERATOR DOES NOT CHARGE THE BATTERY 4 Low engine temperature is Replace the engine oil if it is not of the recommended viscosity causing too low a cranking for the ambient temperature See the Operator s Manual speed for starting 5 The ignition system is weak a If the Ignition indicator lights when the Start switch is held in or has poor connections or check and tighten the connections at the and terminals of the the control is faulty Begin ignition coil T1 Do the Quick Ignition Test under IGNITION ning Spec J SYSTEM in Engine Subsystems If the spark is weak or there is no spark at all service the ignition system as necessary If the Ignition indicator does not light replace the control assem bly 84 THE ENGINE CRANKS BUT DOES NOT START CONTINUED There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 6 The ignition system is weak Do the Quick Ignition Test under IGNITION SYSTEM in Engine or has poor connections Subsystems Spec H Only If there is only a weak spark service the ignition system as necessary If there is no spark hold in th
139. the oil hole on the back of the block is exposed 7 Install the rear bearing plate and fasten with two nuts or capscrews tightened to the specified torque Make sure the rear thrust washer and shim s did not slip out of place during installa tion The crankshaft should turn freely by hand Crankshaft Endplay See Figure 88 After tightening two rear bearing plate nuts or capscrews to the specified torque check the crankshaft endplay at the point shown us ing a feeler gauge 1 Lightly tap the front of the crankshaft with a plastic faced hammer to take up the endplay The endplay should be 0 006 0 012 inch 0 15 0 30 mm 2 If necessary remove the rear bearing end plate and add or remove shims 3 Install the end plate and tighten all nuts or capscrews to the specified torque 4 Make sure the shim and thrust washer are in place and recheck crankshaft endplay Verify that the crankshaft turns freely without binding ENDPLAY HERE FIGURE 88 CHECKING CRANKSHAFT ENDPLAY 75 BEARINGS To replace the crankshaft and camshaft bearings the engine must be completely disassembled Use the special drivers available to drive out the old bearings and drive in the new Support the engine casting so as not to cause distortion or damage to the bore or casting Crankshaft Bearings Crankshaft bearings are available in standard size 0 002 0 010 0 020 or 0 030 inch undersize When installing either the front or rear
140. the stem If a valve face is burned or warped or the stem is worn install a new valve Excess clearance in the intake guide admits air and oil into the combustion chamber upsetting carbure tion increasing oil consumption and making heavy carbon deposits Carbon prevents heat dissipation Clean metal is a good heat conductor but carbon in sulates and retains heat This increases combus tion chamber temperatures causing warping and burning Unburned carbon residue gums valve stems caus ing them to stick in the guide Deposits of hard car bon with sharp points projecting become white hot causing pre ignition and pinging Valve Stems and Guides Check valve stems and guides for wear Figure 68 Use a hole gauge to measure the valve guide bore diameter When valve clearance with the stem exceeds the original clear ance by 0 002 inch 0 05 mm replace either the valve or guide or both as necessary Always regrind the seat to make it concentric with the newly installed guide 64 Valve Stem Seal A valve stem seal is used on the intake valve guides This seal must be replaced each time the valve is removed FIGURE 66 VALVE SPRING COMPRESSOR FIGURE 67 BURNED VALVE FACE 23222233 555222222 42222222 FIGURE 68 VALVE STEM AND VALVE GUIDE BORE DIAMETERS Springs Check the valve springs for free height squareness end wear and tension If the spring ends are worn check the val
141. ting screw to return no load fre quency to 62 63 Hz 51 5 52 5 Hz 5 Check and adjust droop A If droop from no load frequency is more than 3 Hz 3 5 Hz for Model BGD or 4 Hz 8 5 Hz for Model NHD turn the governor sensitivity adjusting screw Figure 17 one turn counterclockwise Disconnect the load and if necessary readjust the gover nor speed adjusting screw to return to 62 63 Hz 51 5 52 5 Hz no load frequen cy Check droop again and repeat the ad justments if necessary B If droop from no load frequency is less than 2 Hz 2 Hz for Model BGD or 3 Hz 2 Hz for Model NHD turn the governor sensitivity adjusting screw Figure 17 one turn clockwise Disconnect the load and if necessary readjust the governor speed adjusting screw to return to 62 63 Hz 51 5 52 5 Hz no load frequency Check droop again and repeat the adjustments if necessary 6 Check governor response under 1 4 1 2 and 3 4 rated loads See Troubleshooting if hunting is unacceptable Carburetor Overhaul Prior to Spec L See Page 28 for Spec L and Later See Figures 22 and 23 Carburetor problems not corrected by mixture or float adjustments are often caused by gummed up fuel passages or worn inter nal parts The most effective remedy is to replace or overhaul the carburetor Overhauling a carburetor consists of complete disassembly thorough clean ing and replacement of worn parts Repair kits are available for gasoline carburetors
142. type of fuel supply sys tem LPG is flammable and explosive and can cause asphyxiation NFPA 58 Section 1 6 requires all persons handling LPG to be trained in proper handling and operating proce dures It is important to understand that the fuel filter sole noid shutoff valve vaporizer and demand regulator EXHAUST MANIFOLD WITH BAFFLE LPG VAPORIZER COILS PRIMING BUTTON TWO STAGE LPG PRESSURE REGULATOR LPG FITTING AND HOSE TO CARBURETOR handle LPG liquid at the same pressure as in the LPG container Depending on ambient tempera ture LPG container pressure can exceed 200 psi 1379 kPa Therefore discharge or leakage from LPG liquid containing components can result in the escape of large volumes of flammable and explo sive gas Purging the LPG System It is imperative that the LPG system be purged before disconnecting fuel system components Large volumes of LPG can be re leased in the process of disconnecting a liquid withdrawal type of LPG supply system See Preparations Page 12 for the proper proce dures and precautions ONE OF TWO REGULATOR MOUNTING SCREWS LPG FUEL SHUTOFF SOLENOID LPG FILTER AND FUEL SUPPLY CONNECTION FIGURE 28 LPG SYSTEM COMPONENTS FOR LIQUID WITHDRAWAL 35 Demand Regulator See Figure 29 The two stage demand regulator delivers vaporized LPG to the carburetor The primary stage receives LPG vapor and liquid at LPG container pressure and reduces it to approxi
143. ury or death Do not smoke if you smell gas or gasoline vapors or are near fuel tanks or fuel burning equipment or are in an area sharing ventilation with such equipment Keep flames sparks pilot flames electrical arcs and switches and other sources of ignition well away LPG is flammable and explosive and can cause asphyxiation NFPA 58 Section 1 6 requires all persons handling LPG to be trained in proper handling and operating proce dures Air Cleaner Assembly Disassembly 1 Remove the crankcase breather hose and air preheater hose gasoline gensets only from the air cleaner housing 2 Remove the air cleaner housing center caps crew and lift off the housing and air filter 3 Remove the three capscrews that secure the air cleaner adapter to the carburetor and lift off the adapter One of the screws is inside the throat of the adapter 24 4 For LPG gensets Spec H only disconnect the leads at Relay K5 or remove the relay and bracket from the air cleaner adapter Reassembly Reassembly is the reverse of disas sembly Use a new gasket between the adapter and the carburetor Take care not to cross thread the in side adapter mounting screw Carburetor And Intake Manifold Assembly Disassembly 1 Remove the air cleaner assembly 2 Disconnect the fuel line and governor rod from the carburetor Large volumes of LPG can be released in the process of disconnecting a liquid withdrawal type of LPG supp
144. ust be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The vent openings in the Clean as necessary stator are restricted with oil and dirt 2 The generator windings are Clean as necessary covered with oil and dirt 3 A rotor or stator winding is Test and service according to TESTING THE GENERATOR in shorted or grounded Generator 4 Voltage regulator VR1 is Test and service according to TESTING THE VOLTAGE REG faulty ULATOR in Generator 96 THE PHASES ARE UNBALANCED 3 PHASE GENSETS There are hazards present in troubleshooting that can cause equipment damage severe personal injury or death Troubleshooting must be performed by qualified persons who know about the hazards of fuel electricity and machinery Read Safety Precautions inside the front cover and observe all instructions and precautions in this manual Possible Cause Corrective Action 1 The connected loads are Shut down the genset and redistribute the loads so that there is distributed unevenly among a difference of less than 10 percent between phases the phases 2 Improper connections have Shut down the genset and reconnect according to the appropri been made at terminal block ate connection diagram in Generator TB1 or the power output cir cuit breakers CB1 CB2 a
145. ve spring retainer for wear Check for height and squareness by placing the spring on a flat surface next to a square Rotate the spring against the square edge to measure its distortion Check the spring tension at the installed height in both the valve open and closed positions using a valve spring tester Replace a weak broken worn or distorted spring Reconditioning Valves and Valve Seats See Figure 69 The interference angle method of valve seating is used on these engines The valve face angle is 44 degrees The valve seat angle is 45 degrees This 1 degree interference angle results in a sharp seating surface between the valve and the top of the valve seat The valves must not be hand lapped because the sharp contact between the valve and the seat will be destroyed This is especially important where chrome cobalt faced valves and seats are used Valve faces must be finished to 44 degrees in a ma chine Each valve must have a minimum of 1 32 inch 0 8 mm margin Figure 70 If the valve has less margin than this it will heat up excessively It will re tain this heat during the compression stroke and pre ignite the mixture causing loss of power and economy This valve is also susceptible to warping and breakage Not all valves can be reconditioned A badly warped valve must be replaced because the amount of grinding required to make it seat correctly removes its margin To make a valve gas tight remove all pit ting f
146. w head such that it will allow equal 2 Turn the main fuel mixture adjusting screw adjustment in either direction If no load frequency has changed because of idle mixture adjustment repeat Step 1 Check output voltage See Generator if output voltage cannot be adjusted to within 10 percent of rated voltage Table 4 Main Fuel Mixture and Droop Adjustments The frequency specifications for 60 Hz gensets are fol lowed in parentheses by the specifications for 50 Hz gensets 1 30 Connect rated load A Load watts is the product of volts V and amps A For Single phase Output Load watts V x A For Three phase Output Load watts 1 73 x V x A average of the three phases A 1 0 power factor obtainable with a re sistance load bank is assumed True rated output might not be obtained if appliances are used as part of the load B See Generator if output voltage cannot be adjusted to within 10 percent of rated volt age Table 4 clockwise until the frequency drops and then counterclockwise until it drops again Adjust it to obtain the highest possible stable frequency For closer adjustments use a CO meter to ad just to 6 896 CO gasoline or 2 496 CO LPG See Troubleshooting if the engine runs roughly Push the adjustment limiter cap on over the mixture screw head such that the cap pointer indicates the current altitude Disconnect the load and readjust the governor speed adjus
147. without all the cooling system components in place See the Installation Manual regarding the minimum free area required for the air inlet to the compart ment or enclosure and the minimum clearance re quired at the discharge opening The engine will overheat if the inlet and outlet openings are too small or are obstructed or if dust has accumulated on the cooling fins Discharge air from the engine can include deadly exhaust gas Therefore do not use engine discharge air to heat the interior of the vehicle PMG See Figure 9 Beginning Spec J the genset is equipped with a PMG permanent magnet genera tor The PMG consists of a multi pole stator bolted to the engine gear case concentric with the crank shaft and six rotating permanent magnets mounted 18 in the flywheel The stator leads exit around the bot tom right side of the engine and terminate in con nector J8 P8 in the vicinity of the starter motor PMG output is regulated by battery charging voltage reg ulator VR2 Output from the PMG recharges the cranking battery and provides the signal for the en gine control board A1 to disconnect the starter and to continue operation when the START switch S1 is released FLYWHEEL PERMANENT MAGNETS STATOR FIGURE 9 PMG BEGINNING SPEC J IGNITION SYSTEM These gensets are equipped with an electronic igni tion system consisting of a rotor module coil ca pacitor spark plugs and associated wiring Energ
148. y for ignition is supplied by the 12 volt cranking bat tery Rotor See Figure 10 The ignition rotor is keyed to the en gine crankshaft The ends have opposite magnetic polarity north and south One pole switches on the ignition module and the other pole switches it off once each revolution of the crankshaft The rotor should not normally require replacement Module The ignition module is secured and grounded to the generator engine adaptor by two cap screws It is an electronic switch in the primary circuit of the igni tion coil See Wiring Diagrams for the appropriate wiring diagram It is switched on and off once each revolution by the rotor The module contains no ser viceable parts and should not normally require re placement Coil See Figure 11 The ignition coil is a transformer that fires the spark plugs at roughly 20 000 volts each revolution when the ignition module opens the pri mary circuit causing the coil field to collapse The leads connected at the low volt age terminals of the ignition coil Figure 11 should not be routed so as to pass between the high voltage terminal posts Otherwise false signals can be induced in the low voltage wires leading to erratic operation ENGINE GENERATOR ADAPTOR IGNITION MODULE IGNITION ROTOR CRANKSHAFT FIGURE 10 IGNITION ROTOR AND MODULE HIGH VOLTAGE TERMINALS LOW VOLTAGE TERMINALS PRIMARY WINDING SECONDARY WINDING FIGU

Caution: This document contains mixed page sizes (8.5 x 11 or 11 x

Contents

Download Pdf Manuals

Related Search

Related Contents