Service parts for the Spec C
Grouped by system, with how many of each the parts manual calls for.
Belts
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Oil capacity | 2.5 L |
|---|---|
| Voltage options | 115 V, 230 V |
Engine
| Oil capacity | 2.5 L |
|---|---|
| Displacement | 0.483 L |
| Aspiration | Four Cycle, Water-cooled |
| Rated speed | 1800 rpm |
Maintenance & consumables
for the Cummins/Onan YK| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | — | 500 hr | |||
| Fuel filter | — | 1000 hr | |||
| Oil filter | — | 500 hr | |||
| Battery | — | ||||
| Belt | Drive Belt | CS-1313-2 | Amazon eBay | ||
| Coolant | — | ||||
| Coolant filter | — | ||||
| Oil | 2.5 L | — | |||
| Spark plug | Check for an open ignition cable or low compression, Check for faulty choke operation, overly rich fuel mixture, or restricted air intake, Check for faulty crankcase breather hose, worn rings, or worn valve guides, Check for leaking intake manifold gaskets, lean fuel mixture, or incorrect ignition timing | — | 500 hr |
Common questions
Which engine powers the Cummins/Onan Spec C?
The Cummins/Onan Spec C is powered by the Cummins/Onan YK engine.
How much oil does the Cummins/Onan Spec C take?
The Cummins/Onan YK engine in the Cummins/Onan Spec C has an oil capacity of 2.5 liters.
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| GENERATOR OVERHEATING | Short in load circuit. Generator overloaded. Improper brush rig position. | Correct short circuit. Reduce the load, Refer to the GENERATOR section of MAINTENANCE - See Brush Rig. |
| ENGINE OVERHEATING | Improper lubrication. Poor ventilation, Dirty or oily cooling surfaces. Retarded ignition timing, Generator overloaded. | Provide ample ventilation at all times. Keep the engine clean, Retime ignition. Reduce load. |
| VOLTAGE DROPS UNDER HEAVY LOAD | Engine lacks power, Poor compression. | Tighten cylinder heads and spark plugs. If still not corrected, grind the valves. Replace piston rings if necessary. |
| VOLTAGE DROPS UNDER HEAVY LOAD (CONT) | Faulty carburetion, Dirty carburetor air cleaner, Choke partially closed. Carbon in cylinders or in carburetor venturi. Restricted exhaust line, Improper governor adjustment. | Check the fuel system. Clean, adjust or repair as needed. Clean and Service. Choke plate must be wide open at operating temperature. |
| ENGINE MISFIRES AT LIGHT LOAD | Carburetor idle jet clogged or improperly adjusted. Spark plug gaps too narrow. Intake air leak, Faulty ignition. | Clean or adjust. Adjust to correct gap - .025"{.018" for gas operation). Tighten manifold and carburetor mounting screws. Replace gasket if necessary. Clean, adjust, or replace breaker points, spark plugs, condenser, etc. |
| ENGINE MISFIRES AT HEAVY LOAD | Defective spark plug. Faulty ignition. Clogged carburetor. Clogged fuel screen. Defective spark plug cable. | Replace. Clean, adjust, or replace breaker points, spark plugs, condenser, etc. or retime ignition. Clean carburetor. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan Spec C troubleshooting guide (29 entries) →
Parts
2| Part # | Description | Qty | System | |
|---|---|---|---|---|
| CS-1313-2 | Drive Belt | 1 | Belt | Amazon eBay |
| 918-0100 | Service part / kit | Amazon eBay $19.00 |
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
Service manual — 918-0500 Onan MME Marne Genset Service manual (06-1990) (Cummins/Onan)Service manual — 920-0014 Onan CW series Genset & Magnet Installation & Service manual (small) (Cummins/Onan)Service manual — 920-0014 Onan CW series Genset & Magnet Installation & Service manual (Cummins/Onan)