Service parts for the RDJC
Grouped by system, with how many of each the parts manual calls for.
Air intake
1 requiredFuel system
1 requiredOil system
1 requiredBelts
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Fuel | diesel |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 15 kW |
| Alternator | YD (4-pole) |
Maintenance & consumables
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Element & Retainer, Air Cleaner | 140-0636 | Amazon eBay | ||
| Fuel filter | Filter, Secondary Fuel (Includes Cartridge) | 149-0408 | Amazon eBay | ||
| Oil filter | Filter, Oil | 122-0185 | Amazon Amazon eBay $19.55 eBay NAPA $12.88 | ||
| Belt | Belt, Fan | 511-0066 | Amazon eBay |
Service intervals
30| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Exhaust system | Inspect | 8 hr | ||
| Fuel supply | Check | 8 hr | See Note 1; if daily inspection shows water or excessive dirt in sediment bowl, check fuel handling and storing facilities | |
| Generator set | Inspect | 8 hr | ||
| Oil level | Check | 8 hr | Check oil level indicator after every 8 hours of operation; maintain at FULL mark | |
| Air cleaner | Check | 50 hr | Note 3: perform more often in extremely dusty conditions; remove and clean filter element after every 50 hours | |
| Crankcase oil | Change | 100 hr | First service — drain while engine still hot, first oil change after break-in | |
| Cylinder head bolts and valve clearance | Adjust | 50 hr | First service — Note 2: tighten head bolts and adjust valve clearance after first 50 hours on new and overhauled engines, then adjust valve clearance each 500 hours thereafter | |
| Head bolts / valve clearance | Adjust | 50 hr | First service — after first 50 hours on an overhauled engine (Note 3) | |
| Valve clearance | Adjust | 50 hr | First service — Adjust after first 50 hours on new and overhauled engines (Note 3) | |
| Battery | Inspect | 100 hr | Check battery condition | |
| Fuel transfer pump sediment bowl and filter | Clean | 100 hr | See Note 1 | |
| Governor linkage | Clean | 100 hr | Carefully pull neoprene governor ball joints apart and clean them; do not lubricate | |
| Oil filter | Replace | 200 hr | ||
| Sediment bowl and filter on fuel transfer pump | Clean | 100 hr | See Note 1 | |
| Air cleaner element | Replace | 200 hr | ||
| Battery condition | Check | 200 hr | ||
| Battery electrolyte level | Check | 200 hr | Check level of electrolyte at least every 200 hours of operation | |
| Crankcase breather | Clean | 200 hr | ||
| Crankcase breather tube | Clean | 500 hr | 500 hour interval coincides with valve lash adjustments | |
| Start-disconnect circuit | Check | 500 hr | ||
| Valve clearances | Check | 500 hr | Note 4: contact an authorized service center for service | |
| Primary fuel filter | Change | 600 hr | ||
| Torsional washers | Inspect | 1500 hr | Note 5: check yearly on non-commercial sets | |
| Generator | Clean | 2000 hr | ||
| Holes in rocker box oil line | Clean | 2000 hr | ||
| Nozzle spray pattern | Check | 2000 hr | See Note 2 - trained diesel injection personnel required | |
| Valves | Other | 2000 hr | Grind valves (if required); Note 4 | |
| Secondary fuel filter | Change | 3000 hr | ||
| Engine | Other | 5000 hr | General overhaul (if required) | |
| General overhaul | Other | 5000 hr | If required; Note 4 |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Service specifications
60| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Clearance | Camshaft bearing clearance limit (original) | 0.0015-0.0030 | in (0.038-0.076 mm) | |
| Clearance | Camshaft bearing clearance limit (replacement) | 0.0012-0.0049 | in (0.030-0.123 mm) | |
| Clearance | Camshaft end play | 0.007-0.039 | in (0.2-1.0 mm) | |
| Clearance | Center main bearing clearance (original) | 0.0024-0.0052 | in (0.061-0.132 mm) | |
| Clearance | Connecting rod end play | 0.010-0.015 | in (0.254-0.381 mm) | |
| Clearance | Cylinder bore maximum allowable out-of-round | 0.001 | in (0.025 mm) | |
| Clearance | Cylinder bore maximum allowable taper | 0.005 | in (0.127 mm) | |
| Clearance | Fan belt deflection | 1/2 | in (13 mm) | about 15 lb (67 N) applied midway between water pump pulley and belt tightener pulley |
| Clearance | Front and rear main bearing clearance (original) | 0.0030-0.0043 | in (0.076-0.109 mm) | |
| Clearance | Piston ring gap | 0.010-0.020 | in (0.25-0.51 mm) | |
| Clearance | Rod bearing clearance | 0.001-0.0033 | in (0.025-0.084 mm) | |
| Clearance | Valve guide clearance, exhaust | 0.0030-0.0050 | in (0.076-0.127 mm) | |
| Clearance | Valve guide clearance, intake | 0.0015-0.0030 | in (0.038-0.076 mm) | |
| Gap | Centrifugal switch point gap | 0.040 | inches | |
| Gap | Start-disconnect centrifugal switch point gap | 0.020 | in (0.51 mm) | |
| Other | Battery specific gravity when 75 percent charged | 1.290 to 1.225 | 75 percent charged | |
| Other | Centrifugal switch closes (start-disconnect) | about 900 | rpm | |
| Other | Cranking limiter limits cranking time | 45 to 90 | seconds | depending on ambient temperature |
| Other | Exhaust valve face angle | 45 | degrees | |
| Other | Governor speed variation (no-load to full-load) | not more than 3 | hertz | |
| Other | High altitude power derate | 4 | % per 1000 ft (310 m) above sea level, after first 1000 ft | |
| Other | Intake valve face angle | 42 | degrees | |
| Other | Valve seat angle | 45 | degrees | |
| Other | Valve seat width | 0.047-0.062 | in (1.19-1.57 mm) | |
| Other | Valve spring load, valve closed | 45-49 | lb (200-218 N) | |
| Other | Valve spring load, valve open (RDJC prior to Spec P) | 83-93 | lb (369-414 N) | |
| Other | Valve spring load, valve open (RDJF, RDJC begin Spec P) | 87-97 | lb (388-432 N) | |
| Other | Voltage adjust rheostat adjustment | plus or minus 5 | percent | |
| Pressure | Cooling system pressure cap rating | 15 | psi | |
| Pressure | Cranking compression pressure at ~300 rpm | 350-400 | psi (2415-2760 kPa) | RDJF and RDJC begin Spec P |
| Pressure | Cranking compression pressure at ~300 rpm (RDJC prior to Spec P) | 300-350 | psi (2068-2415 kPa) | |
| Pressure | Delivery valve maintained line pressure | 300 to 600 | psi (2070 to 4140 kPa) | |
| Pressure | Engine oil pressure at operating temperature | 35 to 55 | psi (241 to 379 kPa) | at operating temperature |
| Pressure | Engine oil pressure, normal operating | 25 or more | psi (172.5 kPa) | |
| Pressure | Exhaust total back pressure of all system components | must not exceed maximum back pressure limits | ||
| Pressure | Fuel injection nozzle opening pressure (factory) | 1900 to 1950 | psi (13,110 kPa) | |
| Pressure | Fuel injection nozzle reset opening pressure | 1750 | psi (12,075 kPa) | |
| Pressure | Fuel transfer pump pressure | 12-14 | psi (83-97 kPa) | at 1800 rpm |
| Pressure | LO OIL PRES shutdown at engine oil pressure | 14 | psi (97 kPa) | |
| Pressure | Low oil pressure shutdown trip point | 20 | psi (138 kPa) | at governed speed |
| Pressure | Maximum cylinder-to-cylinder compression variation | 30 | psi (207 kPa) | |
| Pressure | PRE LO OIL PRES lamp lights at engine oil pressure | 20 | psi (138 kPa) | |
| Resistance | Battery electrolyte specific gravity, fully charged (corrected) | 1.260 | specific gravity | corrected to 80°F (27°C) |
| Resistance | Brushless exciter field leads resistance | 12.2 + 10% | ohms | at 20 C (68 F.) |
| Resistance | Brushless exciter rotor lead pairs T1-T2, T2-T3, T1-T3 | 0.5 to 0.6 | ohms | at 20 C (68 F.) |
| Resistance | Charge battery if specific gravity is below | 1.215 | specific gravity | |
| Resistance | Commutating reactor CMR21 any terminal to reactor frame | infinity | ||
| Resistance | Commutating reactor CMR21 between 1-2 and 3-4 | 0.4 | ohms | |
| Resistance | Commutating reactor CMR21 between 1-3, 2-3, 1-4, or 2-4 | infinity | ||
| Resistance | Generator rotor resistance | 2.05 | ohms @ 20°C (68°F) | 20°C (68°F) |
| Resistance | Generator rotor resistance | 2.30 | ohms @ 20°C (68°F) | 12.5 kW |
| Resistance | Generator rotor resistance | 2.45 | ohms @ 20°C (68°F) | 20°C (68°F) |
| Resistance | Generator rotor resistance | 2.50 | ohms @ 20°C (68°F) | 12.5/15.0 kW |
| Resistance | Generator rotor resistance | 2.70 | ohms @ 20°C (68°F) | 14.5/17.5 kW |
| Resistance | Generator rotor resistance | 2.76 | ohms @ 20°C (68°F) | 20°C (68°F) |
| Resistance | Generator stator resistance | .220, ~, .087, — | ohms @ 20°C (68°F) | Voltage codes 18, 518, 3C, 53C |
| Resistance | Generator stator resistance | .340, ~, 172, — | ohms @ 20°C (68°F) | Voltage codes 18, 518, 3C, 53C |
| Resistance | Generator stator resistance | .460, 498, 224, .294 | ohms @ 20°C (68°F) | Voltage codes 18, 518, 3C, 53C |
| Resistance | Generator stator resistance | 162, 143, 066, .089 | ohms @ 20°C (68°F) | Voltage codes 18, 518, 3C, 53C |
| Resistance | Generator stator resistance | 220, 198, 087, 110 | ohms @ 20°C (68°F) | 12.5/15.0 kW; Voltage codes 18, 518, 3C, 53C |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Recommended fluids
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Coolant | Permanent type anti-freeze / water 50-50 | 11.36 L | Initial fill 1-1/2 gallons anti-freeze with 1-1/2 gallons water (3 U.S. gallons total radiator capacity) | ||
| Engine oil | 5W-30 (multi-grade) | API CD/SE or CC/SE | below 0°C | recommended for ambient 32°F and colder | |
| Engine oil | SAE 10W, 10W-30, 30, 40 (per viscosity chart) | API CD/SD or CD/SE; CC for first fill only | 6.15 L | 6 U.S. quarts plus 1/2 quart for oil filter change; fill to FULL mark | |
| Engine oil | SAE 15W40 | API Classification CC/CD, CD/SG or CE/SG | 6.5 U.S. quarts (6.0 l) | Table 9-2 viscosity/temperature chart: 5W30, 15W40, 10W30/10W40; 15W40 preferred summer. Limited use of 10W-30 for easier starting below 23°F (-5°C) | |
| Engine oil | 15W-40 or 20W-40 | CD/SE | 10°C to 32°C | ambient range 15°F (-10°C) through 90°F (32°C), Onan J Diesel liquid cooled engines | |
| Fuel | ASTM 2-D (No. 2 Diesel) or ASTM 1-D (No. 1 Diesel) | minimum Cetane number of 45; viscosity above 1.3 cSt; low-sulfur fuel with cloud point at least 10 degrees below lowest expected fuel temperature | below 0°C | Use number 1 diesel fuel when ambient temperatures are below 0°C (32°F) or during long periods of light engine load | |
| Fuel | ASTM 2-D (best economy) or ASTM 1-D | ASTM 2-D / 1-D | below 0°C | use 1-D below 32°F (0°C) or during long periods of light/no load; minimum Cetane number 45; low sulfur, pour point at least 10° below lowest expected temperature | |
| Fuel | ASTM 2-D or 1-D diesel | Minimum Cetane number 45 | Use 1-D below 32 F (0 C), during long light/no-load periods, and when pour point requires; use 1-D below 32 F |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Fault codes
12| Code | Name | Meaning | Severity | Action |
|---|---|---|---|---|
| FAULT 1 | Fault 1 (red lamp) | Indicates an undedicated fault; may be field programmed as shutdown or non-shutdown, and as timed or non-timed fault (normally set for timed shutdown). | Shutdown | Nature of fault determined at installation design; correct the fault and reset the control. |
| FAULT 2 | Fault 2 (red lamp) | Indicates same features as Fault 1 (normally set for timed shutdown). | Shutdown | Nature of fault determined at installation design; correct the fault and reset the control. |
| HI ENG TEMP | High Engine Temperature (red lamp) | Indicates engine has shut down because of critically high engine temperature (above 230°F / 110°C) or low coolant level. | Shutdown | Allow engine to cool; check coolant level and replenish; check for obstructions to cooling airflow and slipping fan belt; reset control and restart. |
| LO FUEL | Low Fuel (yellow lamp) | Indicates fuel supply is marginally low. | Warning | Check fuel supply and replenish as required. |
| LO OIL PRES | Low Oil Pressure (red lamp) | Indicates engine has shut down because of critically low oil pressure (14 psi / 97 kPa). | Shutdown | Check oil level, lines and filters; replenish oil if low; reset control and restart; contact service center if oil pressure is 20 psi (138 kPa) or lower. |
| LOW ENG TEMP | Low Engine Temperature (yellow lamp) | Lights if engine temperature is marginally low for starting (70°F / 21°C or lower); may indicate an inoperative coolant heater. | Warning | Check coolant heater power supply, coolant level and heater operation. |
| OVERCRANK | Overcrank (red lamp) | Indicates engine has failed to start during the cranking period. | Shutdown | Check for loss of engine prime, empty fuel tank, fuel leaks, or plugged fuel lines; check filters; reset control and restart. |
| OVERSPEED | Overspeed (red lamp) | Indicates engine has shut down because of excessive speed. | Shutdown | Contact an authorized service center for service. |
| PRE HI ENG TEMP | Pre-High Engine Temperature (yellow lamp) | Indicates engine temperature is marginally high (approximately 220°F / 104°C) or coolant level is low on optionally wired sets. | Warning | Reduce load if possible; check air inlets and outlets and remove obstructions to airflow. |
| PRE LO OIL PRES | Pre-Low Oil Pressure (yellow lamp) | Indicates engine oil pressure is marginally low (20 psi / 138 kPa). | Warning | Reduce load or prepare to shut down; follow troubleshooting step 5/6 procedures. |
| RUN | Run (green lamp) | Comes on when starter circuit opens after set starting. | Info | Indicates all engine systems are normal; no corrective action required. |
| SWITCH OFF | Switch Off (flashing red lamp) | Indicates generator set is not in automatic start mode. | Warning | Move the Run/Stop/Remote switch to the Remote position for automatic starting. |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
12Battery Charge Rate Adjustment adjustment
⚠ Avoid overcharging.
- Set slide tap on adjustable resistor R21 in generator air outlet to give about 2 amperes charging rate.
- If charge winding AC output is below 19 volts on 12 volt battery charge models, 38 volts on 24 volt models, 50 volts on 32 volt models, test charging circuit for opens or grounds.
- If a separate automatic demand control is used, adjust charge rate for maximum 4.5 amperes.
Centrifugal Switch Adjustment adjustment
⚠ Shut down the set and disconnect the battery cable, negative (-) terminal first, before setting the breaker point gap
- Locate the start-disconnect centrifugal switch on the side of the engine, above the oil filter.
- If necessary, loosen the stationary contact and adjust the point gap to 0.020 inch (51 mm).
- Replace burned or faulty points.
Charge Rate Adjustment adjustment
⚠ Avoid overcharging the battery
⚠ Do not smoke or allow any flame, sparks, or arc-producing devices in the battery area
- Locate the adjustable resistor slide tap in the charging circuit, found in the generator air outlet.
- If necessary, increase the charging rate slightly by moving the slide tap up.
- Make small increments of change until the proper rate has been determined.
- Adjust this slide tap only when the engine is stopped.
Fan Belt Adjustment adjustment
⚠ Be sure to tighten nut securely.
- Loosen the nut on the belt tightener pulley shaft.
- Move the shaft left or right in the elongated slot in the pulley mounting bracket.
- Adjust until a deflection of 1/2 inch (13 mm) is obtained with about 15 pounds (67 N) of force.
- Apply force at a point midway between the water pump pulley and belt tightener pulley.
Generator Voltage Check and Adjustment adjustment
⚠ High voltages can cause injury or death; use extreme caution when working on electrical components
Tools: Screwdriver, Wrench
- Move the Run/Stop/Remote switch on the engine control panel to the Run position.
- Move the Phase Selector switch to read generator output current and voltage.
- Insert a screwdriver into the Voltage Adjust potentiometer and carefully loosen the locking nut with a wrench.
- While observing the voltmeter, slowly turn the screwdriver clockwise to increase voltage or counterclockwise to decrease voltage.
- Adjust to the rated nameplate voltage.
- Tighten the locking nut, being careful not to change the adjustment.
- Move the Phase Selector switch to the Off position.
Governor Sensitivity Adjustment adjustment
- Turn the sensitivity adjusting ratchet to adjust governor sensitivity (no-load to full-load speed droop).
- Radiator cooled sets: turn the ratchet clockwise for more sensitivity (less speed drop at full load).
- Radiator cooled sets: turn the ratchet counterclockwise for less sensitivity (more speed drop).
- City water cooled sets: turn the ratchet counterclockwise for more sensitivity.
- After making the sensitivity adjustment, readjust the speed.
Governor Speed Adjustment adjustment
⚠ Excessive droop may be caused by engine misfiring; correct before adjusting governor.
Tools: tachometer
- Turn governor spring nut clockwise (more spring tension) to increase rpm.
- Turn counterclockwise to reduce governed speed.
- Hold a tachometer against the flywheel-crankshaft cap screw or observe a frequency meter.
Valve Clearance Adjustment adjustment
Tools: feeler gauge, socket wrench
- Check valve clearance with engine at room temperature, about 70 F (21 C).
- Turn flywheel until the cylinder to be adjusted is on its compression stroke.
- Turn flywheel clockwise an additional 10 to 45 degrees.
- Loosen locknut to increase clearance; tighten to reduce clearance.
- Check clearance between rocker arm and valve using a feeler gauge.
- Adjust in firing order (1-2-4-3) sequence.
- For #2, #4 and #3 cylinders, turn flywheel 180 degrees clockwise between each.
Voltage Calibration Adjustment adjustment
Tools: AC voltmeter
- If set has a voltage adjust potentiometer (R22) on the meter panel, set pointer halfway between minimum and maximum positions.
- With unit running at no load, turn generator voltage potentiometer R26 on VR21 clockwise to increase output voltage; turn R26 counterclockwise to decrease output voltage.
Voltage Stability Adjustment adjustment
- With generator set running at no load, turn potentiometer R27 to a position where voltage tends to be unstable or hunt.
- Turn R27 clockwise slowly until voltage first stabilizes.
Battery Checkout diagnostic
Tools: hydrometer
- Check charge condition of battery with a hydrometer.
- Specific gravity should be between 1.290 and 1.225 when 75 percent charged. If not, recharge the battery.
- Check electrolyte level. Add approved water to keep electrolyte at its proper level.
- If battery will not recharge, replace it. Keep battery connections tight and clean.
Centrifugal Switch Check diagnostic
Tools: feeler gauge
- The start-disconnect switch is located on the gear cover on the side of the engine above the oil filter.
- The switch opens when engine stops and closes when engine speed reaches about 900 rpm.
- Check switch contacts for pitting. If necessary, loosen stationary contact and adjust point gap at 0.040 inches.
- Replace burned or faulty points.
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Voltage reconnection
| Voltage | Phase | Connection | Leads | Notes |
|---|---|---|---|---|
| 100 | 1 | V4-V1 | 4 lead reconnectable | 50 Hz |
| 100/200 | 1 | V4-V1 | 12 lead reconnectable | 50 Hz |
| 110 | 1 | 518 | V1 | 50 hertz |
| 110 | 1 | V4-V1 | 4 lead reconnectable | 50 Hz |
| 110/190 | 3 | 53C | V1 | 50 hertz |
| 110/190 | 3 | V4-V1 | 12 lead reconnectable | 50 Hz |
| 110/220 | 1 | 518 | V1 | 50 hertz |
| 110/220 | 1 | 53C | V1 | 50 hertz |
| 110/220 | 1 | V4-V1 | 12 lead reconnectable | 50 Hz |
| 110/220 | 3 | 518 | V1 | 50 hertz |
| 115 | 1 | 518 | V2 | 50 hertz |
| 115 | 1 | V4-V2 | 4 lead reconnectable | 50 Hz |
| 115/200 | 3 | 53C | V2 | 50 hertz |
| 115/220 | 3 | V4-V2 | 12 lead reconnectable | 50 Hz |
| 115/230 | 1 | 518 | V2 | 50 hertz |
| 115/230 | 1 | 53C | V2 | 50 hertz |
| 115/230 | 1 | V4-V2 | 12 lead reconnectable | 50 Hz |
| 115/230 | 3 | 518 | V2 | 50 hertz |
| 120 | 1 | 3C | V1 | 60 hertz |
| 120 | 1 | 518 | V3 | 50 hertz |
| 120 | 1 | V4-V1 | 4 lead reconnectable | 60 Hz |
| 120 | 1 | V4-V3 | 4 lead reconnectable | 50 Hz |
| 120 | Single | 3-wire generator, single phase | T1, T2, T3, T4 | Ungrounded load wire and grounded load wire connections |
| 120/208 | 3 | 3C | V1 | 60 hertz |
| 120/208 | 3 | 53C | V3 | 50 hertz |
| 120/208 | 3 | V4-V1 | 12 lead reconnectable | 60 Hz; jumper wire connection on voltage regulator VR21, per representative reconnection diagram (YD generators) |
| 120/208 | 3 | V4-V3 | 12 lead reconnectable | 50 Hz |
| 120/240 | 1 | 3C | V1 | 60 hertz. Connect X1 to VR21-5 for 50 hertz and X1 to VR21-6 for 60 hertz generators. Jumper W10 on VR21 must connect VR21-V4 to V1, V2, or V3 as listed. |
| 120/240 | 1 | 518 | V3 | 50 hertz |
| 120/240 | 1 | 53C | V3 | 50 hertz |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Common questions
How many kW is the Cummins/Onan RDJC?
The Cummins/Onan RDJC is rated 15 kW standby.
What kind of fuel does the Cummins/Onan RDJC run on?
The Cummins/Onan RDJC runs on diesel.
What alternator comes on the Cummins/Onan RDJC?
The Cummins/Onan RDJC uses a YD alternator. It has 4 poles.
Which oil filter part number does the Cummins/Onan RDJC take?
The Cummins/Onan RDJC uses oil filter part number 122-0185.
What fuel filter does the Cummins/Onan RDJC use?
The Cummins/Onan RDJC uses fuel filter part number 149-0408.
What air filter does the Cummins/Onan RDJC use?
The Cummins/Onan RDJC uses air filter part number 140-0636.
Troubleshooting
7Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Engine does not crank. | Battery dead, loose connections, incorrect wiring, or faulty starter motor. | Check 12 VDC to ground at battery BT1 and at starter motor Bl. Check B+ present at TB11, K13, S1, and M11. Check battery cables for polarity and tightness at battery and starter motor. If battery is dead, check if centrifugal switch S1 is open to ground. Replace S4 or charge battery. Jumper battery cable connection to ground at starter. Check starter motor. With S11 at START, jumper K11 contacts to starter solenoid. Start relay K11 is defective; replace it. |
| Engine cranks but does not start. | Faulty switch or lead connections. | Check 12 VDC present between start terminal on S11 and ground (TB11-1) with S11 at START. Check 12 VDC present between M11-B+ and ground TB11-1 with S11 at START. Replace faulty switch S11 if necessary. Check lead from TB12-4 to fuel pump; check fuel pump and replace if necessary. |
| Engine starts but stops when start switch is released. | Faulty switch or lead connections. | Connect voltmeter from 12 VDC to ground at battery BT1 and at starter motor Bl. Check B+ present at TB11, K13, S1, and M11. Check battery cables for polarity and tightness at battery and starter motor. If battery is dead, check if centrifugal switch S1 is open to ground. Replace S4 or charge battery. Jumper battery cable connection to ground at starter. Check starter motor. With S11 at START, jumper K11 contacts to starter solenoid. Start relay K11 is defective; replace it. |
| No build up of AC output voltage. | Is Field Breaker CB21 on control panel ON? If not, step 2. Connect jumper wire across terminals of Field Breaker, CB21. Does AC output voltage build up? If yes, replace Field Breaker. If no, push to reset Field Breaker. Does AC output voltage build up? If yes but is high, low, unstable, or causes tripping of Field Breaker, refer to Tables B, C, or D. If no, step 4. Disconnect alternator stator leads 1 & 2 from TB21-1 and TB21-2 on VR22. Is reference voltage across 1 & 2 20 VAC or more? If not, refer to step 14. | |
| AC output voltage builds up, but is unstable. | Are there any loose or broken wires or connections on voltage regulator assembly VR22? If yes, step 3. Is W9 (exciter field) wiring harness from VR22 to End bell OK? If no, replace PC Board VR21. Do not replace the printed circuit board until the trouble not on the PC board has been located and corrected to avoid damage to new PC board. | |
| AC output voltage builds up, but is high or low. | Is set running at correct RPM? (See appropriate engine manual to set RPM) If no, step 3. Does adjustment of Voltage Adjusting knob for R22 on VR22 result in correct output voltage? If no, step 4. Does adjustment of potentiometer R26 on VR21 result in correct output voltage? If no, refer to step 5. Is correct voltage reference V4 to V1, V2, or V3 on VR21 being used? Refer to Figure 6. If no, replace voltage regulator PC board VR21. Do not replace the printed circuit board until the trouble not on the PC board has been located and corrected to avoid damage to new PC board. | |
| AC output voltage builds up, but Field Breaker trips. | Does AC output voltage build up to 140% or more of rated voltage before Field Breaker trips? If yes, are there any loose or broken wires or connections on VR22? If no, is diode CR15 on VR21 OK? If no, are T21 windings and connections OK? If no, are generator stator leads properly connected? Refer to Figure 6. Replace VR21 if necessary. Are diodes CR1, CR2, CR3, CR4, CR5, CR6 in rotating rectifier assemblies OK? Check all diodes - more than one may be defective. Is brushless exciter stator winding OK? Is generator rotor field winding OK? If no, is brushless exciter rotor windings OK? |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Repair guides
31- Air Cleaner Service
- Automatic Starting and Stopping
- Battery Cleaning and Specific Gravity Check
- Bleeding Fuel System
- Break-In
- Centrifugal Switch Adjustment
- Charge Rate Adjustment
- Contractor Model Air Cleaner Cleaning
- Crankcase Breather Cleaning
- Draining Cooling System
- Emergency Stop
- Exercising the Generator Set
- Fan Belt Adjustment
- Generator Voltage Check and Adjustment
- Governor Sensitivity Adjustment
- Governor Speed Adjustment
- Governor Speed Adjustment
- Normal Stop
- Oil Change
- Oil Filter Change
Step-by-step procedures compiled from the Cummins/Onan service manual for this model.
Parts
67| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 110-0546 | Gasket, Glow Plug | 4 | Gasket | Amazon eBay $9.95 |
| 110-1852 | Gasket, Head | 2 | Gasket | Amazon eBay |
| 120-0547 | Pump Assembly, Oil | 1 | Pump | Amazon eBay $295.00 |
| 120-0580 | Gasket Kit, Oil Pump | 1 | Gasket | Amazon eBay |
| 122-0185 | Oil Filter | 1 | Oil filter | Amazon Amazon eBay $19.55 eBay NAPA $12.88 |
| 122-0188 | Gasket, Oil Adapter | 1 | Gasket | Amazon eBay |
| 122-0325 | Filter, Fuel - Primary | 1 | Fuel filter | Amazon eBay $75.00 NAPA $35.18 |
| 122-0326 | Filter, Fuel - Secondary | 1 | Fuel filter | Amazon eBay $65.00 NAPA $37.59 |
| 132-0072 | Gasket - Water Pump | 1 | Gasket | eBay |
| 132-0082 | Repair Kit, Water Pump (Includes Shaft and Bearing, Impeller, Fan, Hub and Gasket) | 1 | Pump | eBay |
| 132-0101 | Seal | 1 | Seal | Amazon eBay |
| 132-0105 | Fresh water pump, with metal impeller | 1 | Pump | eBay |
| 132-0110 | Pump, Water | 1 | Pump | Amazon eBay |
| 132-0114 | Impeller | 1 | Impeller | Amazon eBay |
| 140-0584 | Gasket, Air Cleaner | 1 | Gasket | Amazon eBay |
| 140-0636 | Element and Retainer, Air Cleaner | 1 | Air filter | Amazon eBay |
| 147-0043 | Nozzle Only (Component of Nozzle & Holder Assembly) | 1 | Gasket | Amazon eBay |
| 147-0044 | Nozzle Only (component of Nozzle & Holder Assembly) | 4 | Injector | Amazon eBay $24.95 |
| 147-0136 | Nozzle & Holder Assembly | 1 | Injector | Amazon eBay |
| 147-0231 | Pump, Injection (Includes Buttons 2, 4, 11, 12, Retaining Ring, Injection Lines and Governor Linkage Ball Joint) | 1 | Pump | Amazon eBay |
| 147-0232 | Pump, Fuel - Injection (includes mounting gasket) | 1 | Pump | eBay |
| 149-0408 | Filter, Secondary Fuel (Includes Cartridge) | 1 | Fuel filter | Amazon eBay |
| 149-0428 | Cartridge, Secondary Fuel Filter | 1 | Fuel filter | Amazon eBay NAPA $20.57 |
| 149-0455 | Gasket, Secondary Filter - Cartridge to Head | 1 | Gasket | Amazon eBay |
| 149-0456 | Gasket, Secondary Filter Bowl to Cover | 1 | Gasket | Amazon eBay |
| 149-0493 | Gasket, Secondary Filter - Cartridge to Retainer | 1 | Gasket | Amazon eBay |
| 149-0517 | Gasket, Fuel Pump Bowl | 1 | Gasket | Amazon eBay |
| 149-0792 | Gasket, Fuel Pump Mounting | 1 | Gasket | Amazon eBay |
| 149-0846 | Cartridge (For 149-1078 Filter) | 1 | Fuel filter | Amazon eBay $39.88 |
| 149-1020 | Pump, Fuel (includes mounting gasket) | 1 | Pump | eBay |
| 149-1046 | Repair Kit, Fuel Pump | 1 | Pump | Amazon eBay |
| 149-1078 | Filter, Fuel - Mounted Between Fuel Tank and Transfer Pump | 1 | Fuel filter | Amazon eBay |
| 154-1057 | Gasket, Exhaust Manifold | 4 | Gasket | Amazon eBay |
| 168-0100 | Gasket Kit, Engine | 1 | Gasket | eBay |
| 193-0104 | Sender Unit - Water Temperature | 1 | Sensor | Amazon eBay |
| 193-0108 | Sender, Oil Pressure Gauge | 1 | Sensor | Amazon eBay $119.99 |
| 212-1064 | Brush, Collector Ring | 1 | Brush | eBay $34.95 |
| 300-0688 | Switching regulator | Avr | eBay | |
| 300-1006 | Board Assembly, Regulator | 1 | Avr | eBay |
| 300-1540 | AVR-A VOLTAGE REGULATOR | Avr | Amazon eBay | |
| 305-0534 | Regulator Assembly, Voltage (Complete) | 1 | Avr | eBay |
| 309-0130 | Thermostat | 1 | Thermostat | Amazon eBay $55.00 NAPA $35.33 |
| 309-0145 | Gasket, Thermostat Cover / Thermostat Chamber | 1 | Gasket | Amazon eBay |
| 309-0178 | Switch, High Water Temperature Alarm - Optional | 1 | Sensor | Amazon eBay $350.00 |
| 309-0179 | Switch, High Water Temperature | 1 | Sensor | Amazon eBay |
| 333-0106 | Plug, Glow - 12 Volt (includes gasket) | 4 | Glow plug | Amazon eBay |
| 503-0204 | Hose, Radiator Curved | 1 | Hose | eBay |
| 503-0400 | Hose, Radiator | 1 | Hose | eBay |
| 509-0086 | Seal, Crankshaft Rear | 1 | Seal | Amazon eBay |
| 509-0088 | Seal, Governor Shaft | 1 | Seal | Amazon eBay |
| 509-0090 | Seal, Oil - Intake Valve | 2 | Seal | Amazon eBay |
| 511-0066 | Belt, Drive | 1 | Belt | Amazon eBay |
| 511-0067 | Belt, Centrifugal Water Pump | 1 | Belt | Amazon eBay NAPA $4.76 |
| 110-1221 | Spring, Valve | 8 | Service part / kit | Amazon eBay |
| 110-1278 | Valve, Exhaust | 4 | Service part / kit | Amazon eBay NAPA $93.84 |
| 110-1320 | Valve, Intake | 1 | Service part / kit | Amazon eBay $49.99 NAPA $215.34 |
| 110-1501 | Guide, Valve | 8 | Service part / kit | Amazon eBay |
| 130-0626 | Pencil, Zinc (Included in Heat Exchanger) | 1 | Service part / kit | Amazon eBay |
| 132-0111 | Repair Kit | 1 | Service part / kit | Amazon eBay |
| 149-0463 | Valve, Check | 1 | Service part / kit | Amazon eBay |
| 304-0500 | Resistor, Tapped (Adjustable) | 1 | Service part / kit | eBay $109.95 |
| 308-0155 | Part 308-0155 | 1 | Service part / kit | Amazon eBay |
| 309-0169 | 1 Begin Spec G 25 26 | 1 | Service part / kit | Amazon eBay |
| 333-0054 | Heater, Water Jacket | 1 | Service part / kit | eBay |
| 522-0212 | Overhaul Kit, Set | 1 | Service part / kit | eBay |
| 522-0264 | Overhaul Kit, Set | 1 | Service part / kit | eBay |
| 625-2758 | Reconnection Diagrams (drawing No. 625-2758, Rev. A, modified 12/1/93) | Service part / kit | eBay |
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.
Available documents
Spec sheet — 967-0221 Onan DJB (spec A-AC) Genset Parts manual (10-1988) (Cummins/Onan)Operator's manual — 974-0124 Onan RDJC RV Operator's Manual (6-1980) (Cummins/Onan)Operator's manual — 974-0127 Onan RDJC Operator's Manual (8-1994) (Cummins/Onan)Parts manual — DK-Kohler (Cummins/Onan)Service manual — 900-0184 Onan YD Generators & Controls Major Service manual (10-1975) (Cummins/Onan)Service manual — 974-0753 Onan RDJC RDJF Diesel Engine Service manual 09-1984 (Onan)
This page was generated from the 6 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.