Onan 7NHM-FA/26105F Service Manual Download Page 17

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Summary of Contents for 7NHM-FA/26105F

Page 1: ...f r A _ e Printed in U S A Service Manual 0 BGM NHM 965 0531 2 96...

Page 2: ...l applicable local state and federal codes GENERATOR VOLTAGE IS DEADLY Generator output connections must be made by a qualified electrician in accordance with applicable codes The genset must not be c...

Page 3: ...6 6 Cooling System 6 7 Ignition System 6 1 0 Cylinder Compression Test 6 13 Crankcase Breather Assembly 6 13 Governor and Carburetor Adjustments 6 14 Fuel System 6 19 Electric Starter 6 35 7 CONTROL 7...

Page 4: ...ter 9 1 Cylinder Heads 9 1 Valve System 9 4 Gear Cover 9 9 Governor Cup Mechanical 9 1 0 Timing Gears and Camshaft 9 1 0 Lubrication System 9 11 Piston Assembly 9 13 Crankshaft 9 1 7 Cylinder Block 9...

Page 5: ...andards 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 p...

Page 6: ......

Page 7: ...earance Cold 0 013 inch 0 33 mm 0 013 inch 0 33 mm Spark Plug Gap 0 025 inch 0 64 mm 0 025 inch 0 64 mm Spark Plug Tightening Torque 8 bs ft 1 0 N m 8 lbs ft 1 0 N m Ignition Timing Begin Spec F 12 BT...

Page 8: ...tening Torque Ignition Timing Begin Spec F Ignition Timing Prior to Spec F LPG Vapor Supply Pressure Range Vapor Withdrawal Only LPG Connection for Vapor Withdrawal LPG Connection for Liquid Withdrawa...

Page 9: ...n Ring 1 top Spec A B sets 0 080 0 081 0 080 0 081 Groove Width 2 03 2 06 mm 2 03 2 06 mm Spec C sets 0 0602 0 0612 0 0602 0 0612 1 53 1 55 mm 1 53 1 55 mm Piston Ring 2 Spec A B sets 0 080 0 081 0 08...

Page 10: ...009 Play 0 15 0 30 mm 0 13 0 23 mm Camshaft Journal 1 3740 1 3745 1 3740 1 3745 Diameter 34 900 34 912 mm 34 900 34 912 mm Camshaft Bearing 1 376 1 377 1 376 1 377 Diameter 34 950 34 976 mm 34 950 34...

Page 11: ...035 0 0025 0 0050 Clearance Exhaust 0 0508 0 0889 mm 0 064 0 127 mm Valve Lifter 0 7475 0 7480 0 7475 0 7480 Diameter 18 987 18 999 mm 18 987 18 999 mm Valve Lifter Bore 0 7500 0 7515 0 7500 0 7515 Di...

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Page 13: ...Manifold 6 10 8 14 Rotor Throuah Bolt 45 55 61 75 Starter Mountino Screws 30 33 41 45 Stator Clamp Screws 10 12 11 16 Adapter to Engine 25 27 34 37 Mounting Screws Adapter to Generator 25 34 Mounting...

Page 14: ...Exhaust Manifold 20 23 27 31 Intake Manifold 14 16 19 22 Rotor Throu_g_h Bolt 45 55 61 75 Starter Mounting Screws 30 33 41 45 Stator Clarno Screws 10 12 14 16 Adapter to Engine 25 27 34 37 Mounting Sc...

Page 15: ...and machines Be familiar with the equipment and know how to use it safely Use the correct tool for the job and check its condition before starting Comply with the warnings in this manual and take spec...

Page 16: ...ontrol Tools Rotor removal tool headless bolt Battery hydrometer Frequency meter Digital multi meter AC and DC Voltage Ohms and Diode Check Loadtestpanelandleads Voltage Regulator Testor and Adaptor 1...

Page 17: ...es into the air and can accumulate in explosive con 5 3 centrations Before disconnecting the LPG fuel line close the fuel shutoff valve s at the LPG container s and move the vehicle outside andawayfro...

Page 18: ...the vehicle framework Make sure that the genset is firmly supported before loosening any mounting bolts or support members A fork lift is recom mended to lift or move the genset IJiwARNINGI Gensets ar...

Page 19: ...erepersonal injury or death Only qualified service personnel with knowledge of fuel electricity and machinery hazards should perform service procedures Review safety precautions on inside cover page T...

Page 20: ...7 Excessive engine wear or damage to engine 8 Carburetor air preheater set incorrectly 2 9 Combustion chamber deposits Corrective Action 1 Reset spark plug gap 2 Replace air cleaner 3a Replace fuel f...

Page 21: ...vel b faulty carburetor float 1 2 1 Lean fuel mixture due to a incorrect float level 1 2 b incorrectly adjusted fuel mixture screws 1 c dirt in carburetor d vacuum leak 2 Contaminated fuel 2 3 Excessi...

Page 22: ...6 Governor mechanism worn excessively 7 Fuel supply problem caused by a Faulty fuel pump 2 b Contaminated fuel supply 2 c Vapor locking 2 d Plugged fuel filter 8 Carburetor icing 2 1 Prior to Spec F...

Page 23: ...e b fouled spark plug c rich fuel mixture 3 Low oil level 4 Low oil pressure switch defective 5 Faulty oil bypass valve 6 Excessive engine wear or faulty oil pump 1 Prior to Spec F only 2 Gasoline mod...

Page 24: ...the joint between the manifold and the muffler and the four mounting bracket screws on the ends of the muffler and withdraw the muffler When installing the muffler make sure the self aligning joint be...

Page 25: ...in severe personal injury or death AIR OUTLET lAWARNINGI Discharge air from the engine can include deadly exhaust gas Therefore do not use engine discharge air to heat the interior of the vehicle See...

Page 26: ...the top of the cylinder heads secure each TRIM STRIP RIGHT SIDE PANEL TRIM STRIP END PANEL 4 Remove the end panel which is secured by four remaining screws along its bottom edge Cooling System Disasse...

Page 27: ...ardening sealer on the flywheel capscrew threads and tighten according to Section 4 Torque Specifi cations 2 Make sure the pieces of insulation used to seal the openings in the inner bulkhead where th...

Page 28: ...is switched on and off once each revolution by the rotor The module con tains no serviceable parts and should not normally require replacement Coil See Figure 6 6 The ignition coil is a transformer t...

Page 29: ...rmine if the problem is in the ig nition system First recheck clean and tighten the connections at the ignition coil terminals See Sec tion 11 Wiring Diagrams for the proper connections at the and ter...

Page 30: ...ad wrench either a 3 8 inch Allen orTorx on the generator through bolt Replace the ignition module if voltage does not jump from approxi mately 1 volt to approximately 12 volts and then back again eac...

Page 31: ...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 cau...

Page 32: ...ect or unplug all voltage and frequency sensitive devices such as TVs ACTUATOR LEVER GOVERNOR ACTUATOR GOVERNOR ROD VCRs computers and other solid state elec tronic devices before making governor and...

Page 33: ...wires should not wrap around the gover nor rod 5 Move the actuator back and forth through its full movement to make certain there is no sticking or binding 6 After installing the top panel hook the sp...

Page 34: ...fuel mixture adjusting screw clockwise until the engine begins to stumble Then counting the number of turns turn the screw counterclockwise until it begins to stumble again Set the screw halfway in be...

Page 35: ...y by hand only 2 Start the genset and let it warm up for ten min utes under 1 2 to 3 4 rated load 3 Disconnect the load checkforzeroamps Pull the governor rod so that the tang on the throttle lever be...

Page 36: ...cap pointer indicates the current altitude gasoline carbu retors 6 18 4 Disconnect the load and readjust the governor speed adjusting screw to return no load fre quency to 62 63 Hz 5 Check and adjust...

Page 37: ...ls 4 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 Prior to Spec D gasoline and Spec F...

Page 38: ...g over the end of the preheater hose and insert it into the collar AIR PREHEATER AND HOSE gasoline gensets only MANIFOLD GASKET ADAPTOR TO CARBURETOR GASKET AIR CLEANER ADAPTOR AIR FILTER ELEMENT AIR...

Page 39: ...LTER AIR CLEANER ADAPTER CHOKE COVER FIGURE 6 16 AIR INTAKE ASSEMBLY PRIOR TO SPEC D GASOLINE AND SPEC F LPG INTAKE MANIFOLD AIR PREHEATER GOVERNOR ROD 0 _J l CARBURETOR 1 J__ v FUEL FILTER FIGURE 6 1...

Page 40: ...performed and 2 that the carbu retor is actually malfunctioning by carefully follow ing the troubleshooting procedures in Trouble shooting 6 22 LPG carburetors are usually not the cause ofprob lems Ma...

Page 41: ...at assembly parts then remove the hinge pin float and needle valve Cleaning and Inspection 1 Soak all metal components not replaced by the repair kit in carburetor cleaner Do not soak any rubber or pl...

Page 42: ...g to adjust the height lA CAUTION Remove the float before bend ing the tang so as not to damage the soft nose of the needle valve 3 Install the float bowl and the main mixture screw assembly 4 Install...

Page 43: ...position The marks on the choke housing are spaced at 5 intervals 5 Rotate the element cover as specified then tighten the cover mounting screws HOUSING ELEMENT COVER 6 Move the choke lever to test i...

Page 44: ...ke Pulloff Diaphragm Adjustment The choke pulloff diaphragm partially opens the choke plate after engine startup This inhibits flooding and promotes smooth engine operation as the set warms up 1 Remov...

Page 45: ...setting and clockwise for a leaner setting and retighten the screws The choke plate opening should be checked with a gauge each time the vacuum break is remounted Check and readjust the opening as fol...

Page 46: ...plied pump is being used If it is high when the vehicle engine is running 6 28 a separate fuel pickup tube in the fuel tank or equivalent means will be required If the fuel pressure is less than 3 5 p...

Page 47: ...ner 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...

Page 48: ...est 1 Connect a pressure gauge to the primary pres sure test port and a source of compressed air at least 80 psi 550 kPa to the inlet port 2 The gauge should indicate approximately 1 5 psi 1 0 3 kPa a...

Page 49: ...ing solvents are flammable and corrosive and can cause burns and inflammation Follow the manufacturer s instructions 6 Wipe the magnet clean of the particles it has collected 7 Install a clean filter...

Page 50: ...handling LPG to be trained in properhandling andoperatingproce dures SOLENOID PIGTAIL CONNECTIONS AT THE GENSET GAS SUPPLY HOSE TO THE CARBURETOR INLET MOUNTING BRACKET FUEL SHUTOFF SOLENOID VALVE VEN...

Page 51: ...nections at the genset 6 33 Demand Regulator Lock Off Pressure Test Lock off pressure is determined as follows by pres surizing the back vent side of the regulator dia phragm to simulate carburetor ve...

Page 52: ...er lock off pressure adjust ments have been attempted 4 If the genset is mounted in a compartment make sure the vent pressure balance hose is routed properly to the outside 5 Reconnect the hose to the...

Page 53: ...WASHER RETURN SPRING I i Starter Disassembly Motor Disassembly See Figure 6 31 Remove the starter from the genset The drive housing mo tor frame and end bell are separable after the motor through bol...

Page 54: ...MUTATOR BARS FIGURE 6 33 TESTING ARMATURE FOR GROUNDS 6 36 Testing Armature for Shorts Use a growler Fig ure 6 34 to locate shorts in the armature Place the armature in the growler and hold a thin ste...

Page 55: ...brush spring contact loop to bend the spring back so that each brush can be inserted into the holder Be sure that all brush wires are facing up 6 If the brushes are at least 0 430 inch 1 0 9 mm long r...

Page 56: ...H TERMINAL TORQUE TO 25 30 LBS IN 2 83 3 39 N M I NEGATIVE BRUSH TERMINAL shaft and line up the hole with a hole in the shaft C Support the plastic retainer with a vise or other solid surface Using a...

Page 57: ...speed governing electronic governor sets only SPARK PLUGS TOP ACCESS TO FRONT AND REAR PLUG OIL DRAIN KNOB 3 8 INCH SQUARE DRIVE POSITIVE BATTERY CONNECTION AC OUTPUT LEADS 60 INCHES 1 5 M LONG 4 __NE...

Page 58: ...e holder use only Onan supplied fuses Start Solenoid K1 The K1 start solenoid opens and closes the circuit between the starter motor and the battery The starting current load requires that the solenoi...

Page 59: ...regulator is protected from moisture and other contamination reducing the risk of com ponent failure The capacitor and the printed circuit board are encased in the regulator housing with a potting co...

Page 60: ...T STOP PANEL OPT IOI AL P2 1 I 1 sr r r 1 P1 P2 I i_ J LLJ I I I I L BUt LO UP EXCITOR I I I I A I I I I r 1 I 1d I I a ______________ I I I I Kll I a ___________ I I l I u_ ____ sh I U p 1 LP SHUTDOW...

Page 61: ...voltage activates the choke heater element through a separate connec tion opening the choke and powering the fuel pump and fuel solenoid Energizing K2 opens a set of contacts to de ener gize K4 and c...

Page 62: ...STATOR HOU BRUSH BLOCK ASSEMBLY VOLTAGE REGULATOR ASSEMBLY J3 CONTROL PANEL ASSEMBLY FIGURE 7 3 BGM NHM CONTROL COMPONENTS MECHANICAL GOVERNOR GENSETS ONLY 7 6 G1212 5...

Page 63: ...RY STARTER AND GENERATOR WIRING HARNESS CONNECTOR P1 ENGINE WIRING HARNESS CONNECTOR P3 REMOTE CONTROL WIRING HARNESS CONNECTOR P2 START STOP ES1774 SWITCH S1 RGURE 7 4 BGM NHM CONTROL PCB ASSEMBLY A1...

Page 64: ...see Figure 7 5 Control panel assembly Printed circuit board A1 Start Run Stop switch 81 Fuse Fi e Start solenoid K1 Fuel pump E3 and fuel valve solenoid Remote start control optional Circuit breaker...

Page 65: ...el pump E3 is energized at the same time that start solenoid K1 is energized Spec D gensets 7 9 E3 is activated through K4 contacts See the set schematic diagram in Section 11 of this manual Remote St...

Page 66: ...r can signal the governor controller board to shut the engine off un der the following adverse conditions If power B is lost to the controller If genset speed goes beyond 2700 RPM 7 10 If oil pressure...

Page 67: ...y _ I I I r I I I Y I l l 1 I I STAR fl I I 1 GOVERNOR 0 1 I I I I I c I r _ I I I I I I 1 I IOVFR SPEED I s I I I REMOTE _I J L I I 1 1 I I I I I I I I I I 1 I I I I I I I I I I I __ j L I __ _ __ NO...

Page 68: ...other circuit to the fuel pump and ignition coil af ter K3 is de energized Starter Lockout Run When the engine cranks the low oil pressure switch is bypassed until the engine reaches operat ing speed...

Page 69: ...GOVERNOR CONTROLLER 1 _ ASSEMBLY M VOLTAGE REGULATOR ASSEMBLY VR1 _ l MAGNETIC ____ J CIRCUIT BREAKERS CB1 CB2 FIGURE 7 8 BGMINHM CONTROL COMPONENTS ELECTRONIC GOVERNOR GENSETS ONLY 7 13 G1212 4...

Page 70: ...BATTERY STARTER ENGINE AND GENERATOR WIRING HARNESS CONNECTOR P1 FUSE F1 START STOP SWITCH S1 FIGURE 7 9 BGM NHM CONTROL PCB ASSEMBLY A1 REMOTE CONTROL WIRING HARNESS CONNECTOR P2 ES1774...

Page 71: ...utions on Inside cover page Trouble Possible Cause Engine Does 1 Control fuse F1 may be open Not Crank 2 If engine cranks at set but not at remote control panel fault is due to a PC board P2 J2 connec...

Page 72: ...rk plugs faulty plug wires faulty ignition coil or control module 2 Faulty tuel system due to low fuel level in tank supply valve not open sticking choke faulty fuel pump fuel solenoid or carburetor m...

Page 73: ...ontrol b No output voltage from generator 4 Defective control PC board A1 1 Weak or discharged battery due to a Low electrolyte level in battery b Long periods of non use c Improperly wired battery 2...

Page 74: ...rt stop switch S2 2 Open circuit between ground terminals on lamp or meters and terminal 1 on remote start stop switch 3 If battery condition meter and run lamp work but time meter does not operate ti...

Page 75: ...l to switch is burned out 6 1f remote switch functions OK starting and stopping genset but meters and run lamp do not operate current sensing resistor R4 on control board A1 has opened caused by a sho...

Page 76: ...the voltmeter should be grounded at connector 7 20 P1 8 If the voltmeter indicates zero volts re place control board A1 If the voltmeter indi cates at least 9 volts the problem is not with the control...

Page 77: ...C contacts of K2 Ignition coil E1 is energized Start solenoid K1 solenoid fuel valve E3 and fuel pump E2 are activated After initial start K2 on the control board is activated opening the exciter cir...

Page 78: ...ailure The capacitor and the printed circuit regulator housing with a potting compound The wiring harness plug in P4 is treated with a lubricant prior to connection Circuit Breakers CB1 CB2 AC output...

Page 79: ...set output load changes can significantly decrease or increase en gine speed If the governor does not maintain 8 3 proper engine speed too large a burden may be imposed on the voltage regulator for p...

Page 80: ...ATOR r STATOPRS CLAM THRO l l ocT _ l 11 J _ TERMINAL 11 LOCK TB1 SLIP RINGS o MOUNTING BRACKET CIRCUIT BREAKERS CB1 CB2 BRACKET RELAY ASSEMBLY F D f WIRE L ESS 0 TO LOAD START SOLENOID K1 MECHANICAL...

Page 81: ...pen circuit between generator windings 01 02 and voltage regulator 4 Open circuit between terminal block TB1 and voltage regulator wiring harness J4 leads 5 Brushes stuck in holder or not making good...

Page 82: ...e is incor rect voltage regulator is defective 5 Open grounded or short circuit in rotor or stator 1 Loose brush holder 2 Worn generator end bearing 3 Rotor and stator rubbing together due to a Varnis...

Page 83: ...use 1 Generator overloaded due to defective circuit breaker 2 Airflow restricted due to dirt or debris covering vent openings in stator housing 3 Stator windings covered with oil or dirt 4 Open ground...

Page 84: ...important safety instructions 5 Disconnect the leads to the charge resistor the low oil pressure cut off switch and the B terminal on the ignition coil 6 Remove the brush block cover and disconnect t...

Page 85: ...m the set 14 Disconnect the lead wires attached to the starter motor Loosen the fasteners that mount the starter to the stator housing and remove the starter 15 Remove the four capscrews lock washers...

Page 86: ...tor leads T1 T2 T3 and T4 from terminal board TB1 8 10 01 02 F1 and F2 from voltage regulator VR1 harness J4 81 and 82 from control printed circuit board harness J1 C Pull the stator leads from the co...

Page 87: ...Ignition Rotor Removal Replacement To remove the ignition rotor simply pry it off using a dull edged pry bar or other implement To install the ignition rotor place it over the end of the crank shaft l...

Page 88: ...pter The rotor end bearing should fit snugly into the bearing bore hole lA CAUTIONI Careless handling of the stator can resultIn damage to the statorwindings Do not brush the stator windings against t...

Page 89: ...e the brush block cover and inspect the brushes and brush holder for burns or other dam age If the brushes appear to be in good condition use a piece of wire marked as shown in Figure 8 9 to check for...

Page 90: ...Slip Ring Service Procedure 1 Remove the air cleaner cover and air cleaner filter 2 Disconnect the lead wires from the brush block terminals and then insulate the lead wire ends Tie the lead wires to...

Page 91: ...access to the slip rings remove the brush block cover Lift the brush lead wires and insert a brush retaining wire from outside stator housing through brush block assembly to hold the brushes off the...

Page 92: ...leads individually A read ing less than one megohm indicates a ground Re place a grounded stator with a new stator Open or Shorted Windings Test To test for opens disconnect the following leads Stator...

Page 93: ...G1214s FIGURE 8 13 TESTING STATOR FOR GROUNDS 8 17 TEST LEADS T1 f2 T3ff4 81 82 AND Q1 Q2 FOR OPEN OR SHORTED WINDINGS 81 82 G1214s 1 FIGURE 8 14 TESTING STATOR FOR OPENS OR SHORTS...

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Page 95: ...dapter 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 thread...

Page 96: ...ill be in contact with each other Install a flat washer and nut on each of the four bottom studs 9 2 COMPRESS HEAT TREATED WASHERS lljII NUTS HEAD 6 LONG 4 SHORT STUDS HEAD STUDS HEAD _HEAD GASKET M19...

Page 97: ...4 NHM CYLINDER HEAD TIGHTENING SEQUENCE BGM CLEARANCE M1871c NHM VALVE INSERT VALVE GUIDE VALVE STEM SEALONTAKE ONLY FIGURE 9 5 VALVE SYSTEM 9 3 VT10 U VT1005s ROTAIDR EXHAUST ONLY NOTE ON LPG NHM VAL...

Page 98: ...is exposed to intense heat Out of round wear re sults from warping when the seat is pounded by a valve whose head is not in line with the stem and guide If a valve face is burned or warped or the stem...

Page 99: ...egrees This 1 degree interference angle results in a sharp seating surface between the valve and the top of the valve seat see Figure 9 9 9 5 VT1021s FIGURE 9 9 VALVE INTERFERENCE ANGLE The valves mus...

Page 100: ...lso replaceable from the valve cham ber after the valve assemblies are removed first Valve Guide Removal Procedure 1 Before removing the valve guides use an elec tric drill with a wire brush to remove...

Page 101: ...1 After the old seat has been removed clean out carbon and metal burrs from the seat insert re cess Usea valve seat insert driverand a ham mer to install the insert 2 Insert the pilot of the driver in...

Page 102: ...haft until the TDC mark on the flywheel is lined up with the TDC mark on the gear cover This should place the left piston 1 at the top of its compression stroke Verify that the left intake and exhaust...

Page 103: ...the nylon lined smooth hole in the governor cup See Figure 9 15 2 Turn the governor cup so the nylon lined hole is at the three o clock position Use a small amount of grease to help hold the cup in po...

Page 104: ...s removed from the engine If necessary the engine may be tilted up to install the cup and flyballs 1 Put the flyballs between the spacer arms and install the cup on the center pin 2 Lock the cup in pl...

Page 105: ...he oil base Oil Pump The oil pump Figure 9 18 is mounted on the front of the crankcase behind the gear cover It is driven by the crankshaft gear The inlet pipe and screen assembly is attached to the p...

Page 106: ...follows 1 Remove the 3 8 24 x 7 8 in BGM or 3 8 24 x 1 in NHM capscrew behind the gear cover and under the governor arm 2 Remove the spring and plunger with a mag netic tool 3 Determine the proper val...

Page 107: ...he handle end of a hammer Be 9 13 careful not to scratch the crankpin or the cylin der wall when removing these parts 4 Mark each piston and rod assembly so they can be returned to their respective cy...

Page 108: ...ill cause pis ton damage Use only parts cleaning solvent for this job Make certain to follow the solvent manufacturer s Instructions When cleaning the connecting rods in solvent make certain to includ...

Page 109: ...eter to measure the piston diameter at the point shown in Figure 9 25 When the cylinder bore is see Cylinder Block section the piston diameter from the cylinder bore diameter to obtain the piston to c...

Page 110: ...then close until the expander ends butt together Locate the expander gap 180 degrees from the ring gap Make certain that the piston ring gaps are not aligned with one another EXPANDER CT1047s RGURE 9...

Page 111: ...e crank case Crankshaft Inspection Inspect the rod and main bearing journals If they are worn or scored and cannot be smoothed by polishing either the journals should be reground to fit one of the sta...

Page 112: ...by the cylinder block assuring alignment of the crankshaft and cylinder bores Cylinder Block Cleaning After removing the pistons crankshaft cylinder heads etc inspect the block for cracks and ex treme...

Page 113: ...as D the cylinder bore diameter perpendicular to crank shaft at the bottom of piston travel E Reading A subtracted from reading B and reading C subtracted from reading D indicates the cylinder taper...

Page 114: ...rt overlapping strokes about 40 times per minute Usually 9 20 the bottom of the cylinder must be honed first because it is smaller As the cylinder takes a uniform diameter move the hone up and down th...

Page 115: ...lubricating oil 9 21 2 Position the front bearing so that the oil hole in the bearing is aligned with the oil hole see Fig ure 9 33 in the block AUGN HOLE If ___ __ BEARING WITH HOLE IN BEARING BORE 7...

Page 116: ...ce bearing with attached thrust wash er as shown in Figure 9 35 Do not add an addi tional thrust washer to this front bearing 9 22 NOTE DO NOT ADD ADDITIONAL THRUST WASHER WHEN REPLACING FRONT BEARING...

Page 117: ...24 6 0 5 mm THIS SURFACE SHOULD BE CLEANED OF ALL OLD SEALING COMPOUND BEFORE GEAR COVER OIL SEAL INSTAlliNG SEAL FIGURE 9 36 OIL SEALS 9 23 REAR BEARING PLATE OIL SEAL THIS SURFACE SHOULD BE CLEANED...

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Page 119: ...and check that the choke is completely open Adjust governor mechanical governor gensets as speci fied in the Governor section of this manual lACAUTION IVoltage frequency sensitive equip ment such as V...

Page 120: ...t the generator set several times at the set control and remote control to verify that it func tions properly MECHANICAL Stop the generator set and inspect it for leaking gaskets loose fasteners damag...

Page 121: ......

Page 122: ...vered in this manual are listed below WIRING DIAGRAM DRAWING NO PAGE BGM NHM Spec A Schematic Wiring Diagram 611 1186 rev A 11 2 BGM NHM Spec B Schematic Wiring Diagram 611 1196 rev D 11 3 BGM NHM Spe...

Page 123: ...I E I E LOAD LOAD l 120VI _ffil l __ I I I I CB2 1 I I I I TBI b 120V GND VRI 14 P41 AI I I I I I I I I I I I I I I I I I II l wttr l I I I I _j 1 r d II Ill I ill 1 GJ J IL G2 T p CR9 S2 lPMI WIRING...

Page 124: ...RESISTOR FUEL PUMP RESISTOR BATTERY CHARGE RELAY FUEL PUMP RELAY STOP LATCH RELAY START SOLENOID CHOKE GASOLINE ONLY GENERATOR FUSE SLOW BLOW 5A FUSE SLOW BLOW 5A SOLENOID FUEL VALVE FUEL PUMP SPARK...

Page 125: ...3 l d b T b F f Pl b I II 1 j I I I i I I I jlI i 1 i I I I I I II I_A i I I Iu j I rl I I t I I Gl L_ l I Cl I F2 I 1 I 1 1 l I I il I I I f I I i I I 1 I 1 I I I I I I 1vR 1 I I l I i I I I II L ti...

Page 126: ...I S3 IGN MODULE l S2 I I I iSWITCH LOW OIL PRESSURE R I RES IS 1 OR BATTERY CHARGE K2 GOVERNOR ACTUATOR I RELAY START SOLENOID HI I CHOKE GASOLINE ONLY l G I GENERATOR F I FUSE I OA i E4 SOLENOID FUE...

Page 127: ...D I 120VI 1 4 120V GN CB2 1 1 d lBI I GJ J 7 II G2 Tl l I I I I I l I I I I I I I r A_ I ITJJ P21Lf 121 J I I I I I J START l 82 0 L_r WIRING DIAGRAM 11 4 I f Pl 6 PI G__ Al l IAIL__I I 1 f a L A GI F...

Page 128: ...N COIL IGN MODU E SWITCH LOW OIL PRESSURE RESISTOR BATTERY CHARGE GOVERNOR ACTUATOR RELAY START SOLENOID CHOKE GASOLINE ONLY GENERATOR FUSE lOA SCLENOID FLn VALVE FlEL Pl Ml OR FlEl FILTER LP SPARK PL...

Page 129: ...OAD LOAD L I 120VI rJ 120V GND I L J CB21 I II I TBI I LO VRI J IIc Y4 P 4 I j i HI J7 STOP START GJ II G2 Tl S2 I PMI WIRING DIAGRAM 11 5 2 Rl AI I I L lM __I I I l L L...

Page 130: ...EII PMT Ill Yll TAGE REGILATM IGN COIL IGN MODtli SWITCH lOW OIL PREsstRE RESISTOR BATTERY CHARGE RELAY GOVERNOR ACTUATOR RELAY START SOLENOID CKIKE GBERATOR FUSE lOA FUSE lOA SOLENOID FUEL VALVE FIE...

Page 131: ...trol circuit boards for proper functioning Two Onan product support bulletins are also reprinted in this supplement as follows Subject Page Set Dies When Switch Released PSB 563 A 7 Rotor Stator Check...

Page 132: ...nt side of the board up 7 1 8 2 P1 9 3 10 4 J2 11 5 12 6 0 i WI IN PLACE FOR R IIIII T ES2051 IAWARNING I Use extreme caution when working on operating generator sets Operating generator sets prG sent...

Page 133: ...2 1 P1 9 J2 1 P1 12 J2 1 P1 7 P1 10 Meter Reading 10 12 VDC 10 12 VDC 10 12 VDC 10 12 VDC 10 12 VDC RUN GENERATE MODE With the generator set running and the switch in the Center position Meter Test Le...

Page 134: ...the engine over Does the test light flash bright then dim Yes The module is ok do not replace the module No Go to Test 2 Note If the primary winding of the ignition coil is open the light will not co...

Page 135: ...MODE With the switch in the Center positiion and the unit not running Meter Test Lead Meter Reading P1 7 P1 1 12 13 VDC P1 7 J2 1 12 13 VDC Note Care must be taken not to touch more than one P1 pin a...

Page 136: ...1 4 J2 1 8 9 then 10 12 VDC P1 6 J2 1 9 10 then 11 13 VDC P1 12 J2 1 8 9 then 10 12 VDC RUN GENERATE MODE With the generator set running and the switch in the Center position Meter Test Lead Meter Rea...

Page 137: ...Lead U Check Rotor Stator and Brushes per PSB 564 L J Checks OK OVDC Check VDC between AVR Pin 10 and Ground 9 12VDC A1 Board Check 1 OK out per Card 900 0254 White Plug 900 0265 Blue Plug 1 93 Troub...

Page 138: ...Retest Stator Yes Dynamic running Check Unplug AVR P4 J4 Start the unit and apply Battery 12 VDC 1 to the Brushes and Jumper B to the Ignition Coil When Running Measure Output Voltages L1 LO P4 2 P4 3...

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Page 140: ...Onan Onan Corporation 1400 73rd Avenue N E Minneapolis MN 55432 1 600 688 0NAN 1 1 m ll ij Telex 275477 Fax 612 574 8087 r...

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