Specifications
Ratings spec sheet not in our library yet — see the documents below.
Filters & service parts
model family| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | 00-031 | 0 hr | eBay | ||
| Fuel filter | 149-2206-01 | 1000 hr | eBay | ||
| Oil filter | 122-0645 | 200 hr | eBay | ||
| Belt | — | find | |||
| Coolant | — | 1000 hr | |||
| Oil | 1.7 l | — | 200 hr |
Compiled from this model's family documentation — may include parts for closely-related variants. Confirm the exact part for your serial number.
Common questions
What oil filter does the Cummins/Onan E125 use?
The Cummins/Onan E125 uses oil filter part number 122-0645.
What fuel filter does the Cummins/Onan E125 use?
The Cummins/Onan E125 uses fuel filter part number 149-2206-01.
What air filter does the Cummins/Onan E125 use?
The Cummins/Onan E125 uses air filter part number 00-031.
Troubleshooting
5Symptoms & remedies
| Symptom | Remedy |
|---|---|
| Engine Overspeeds | - Check Governor adjustment - Check Throttle cable |
| Engine Power Output Low | - Check Governor - Check Throttle cable - Check Carburetor choke - Check Fuel filter - Check Air cleaner element - Check Fuel pump - Check Carburetor - Perform checks in Step 01 - Perform engine leak down test |
| Engine Runs Rough or Misfires | - Check Spark plugs - Check Fuel supply - Perform checks in Step 01 - Check Fuel filter - Check Fuel pump - Check Carburetor choke - Check Carburetor - Check Spark plug wires - Check Ignition coil - Check Engine electrical ground |
| Engine Surges | - Check Fuel supply - Check Fuel filter - Check Fuel pump - Check Plugged idle jet - Perform checks in Step 01 |
| Lubricating Oil Consumption Excessive | - Check: -01 - Oil consumption report - For external oil leaks - For overfilled oil pan - Oil specifications - For fuel contamination - Oil change interval - For engine oil in torque converter - Perform checks in Step 01 (0.4 hours) - Check: - Oil temperature - Air compressor oil consumption - Turbocharger seal - Crankcase blowby - Perform checks in Step 02 if problem not located in Step 01 (additional 0.6 hours, total 1.0 hours) |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Parts
44model family| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 00-026 | Intake manifold gaskets | - | Gasket | eBay |
| 00-037 | Troubleshoot − Engine Starts But Will Not Keep Running | 1 | Engine | buy |
| 00-101 | Engine - Remove and Install | 1 | Engine | buy |
| 00-203 | Engine - Rebuild (Gas Engine) | 1 | Engine | buy |
| 01-112 | Crankshaft - Remove and Install | 1 | Crank | buy |
| 01-121 | Gear Cover - Remove and Install | 1 | Cover | buy |
| 01-1AB | Governor, mechanical | Mechanical | buy | |
| 01-304 | Crankshaft Seal,Front − Replace | 1 | Seal | buy |
| 01-308 | Crankshaft Seal, Rear - Replace (Horizontal) | 1 | Seal | buy |
| 01-311 | Crankshaft seal, front | Seal | buy | |
| 01-3AB | Gear Cover Gasket - Replace | 1 | Gasket | buy |
| 01-541 | Cylinder Block - Hone or Bore | Block | buy | |
| 02-104 | Cylinder Head - Remove and Install | - | Head | buy |
| 02-302 | Valve guides | Guide | buy | |
| 02-3AA | Cylinder Head Gasket - Replace | - | Gasket | buy |
| 02-513 | Valves - Grind | Valve | buy | |
| 122-0737 | Filter | 1 | Oil filter | eBay FridayParts $42.99 |
| 140-2331 | Air Cleaner Element | Air filter | buy | |
| 140-2335 | Air Cleaner Element Wrapper (If Equipped) | Element wrapper | buy | |
| 149-2206-01 | Fuel Filter | 1 | Fuel filter | eBay |
| 167-0765 | Spark Plug | Spark plug | buy | |
| 00-021 | Troubleshoot − Engine Cranks But Will Not Start | 1 | Service part / kit | FridayParts $39.70 |
| 00-024 | Troubleshoot − Engine Difficult To Start | 1 | Service part / kit | buy |
| 00-027 | Fuel pump | - | Service part / kit | eBay |
| 00-028 | Carburetor | - | Service part / kit | eBay |
| 00-031 | Ignition coil | - | Service part / kit | eBay |
| 00-040 | Engine mounting | - | Service part / kit | eBay |
| 00-044 | Troubleshoot − Engine Will Not Crank Or Cranks Slowly | 1 | Service part / kit | buy |
| 00-045 | Exhaust system | - | Service part / kit | eBay |
| 00-901 | Administrative Time - Open/Close Repair Order (Shop) | 1 | Service part / kit | buy |
| 01-140 | Piston and connecting rod assembly | 1 | Service part / kit | buy |
| 01-1AA | Connecting Rod - Remove and Install | 1 | Service part / kit | buy |
| 01-3AC | Piston Rings - Replace | 1 | Service part / kit | buy |
| 01-3AD | Governor linkage | Service part / kit | buy | |
| 01-3AE | Camshaft | 1 | Service part / kit | buy |
| 12-18 | (12-18 lb-in) | Service part / kit | buy | |
| 35-40 | Flywheel Capscrew ............-. | 29 | Service part / kit | buy |
| 90-102 | Service part / kit | buy | ||
| 965-0174 | E124V Floorcare | Service part / kit | buy | |
| 965-0178 | E125V/ E140V | Service part / kit | buy | |
| 965-0179 | E125H I E140H | Service part / kit | buy | |
| 965-0180 | P218V I P220V | Service part / kit | buy | |
| 965-0183 | P248V Floorcare | Service part / kit | buy | |
| C851D8 | pin (1/8 inch drill bit) | 1 | Service part / kit | buy |
Compiled from this model's family documentation — may include parts for closely-related variants. Confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.
Available documents
Operator's manual — 965-0165 Onan E125V Operator's Manual (2-1989)Parts manual — DK-Kohler (Cummins/Onan)Service manual — 900-0602C Onan Elite E124-E140 Repair Times (Cummins/Onan)Service manual — 965-0178 Onan E125V E140V Elite series Operator's manual (07-1997)Service manual — 965-0179 Onan E125H E140H Elite series Engine Operator's manual (07-1997)Service manual — 965-0180 Onan P218V P220V Performer series Engine Operator's manual (07-1997) (Cummins/Onan)Service manual — 965-0758 Onan E125H E140H Elite series Engine Service manual 01-1996 (Cummins/Onan)