Service parts for the 25 GEAF
Grouped by system, with how many of each the parts manual calls for.
Oil system
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Fuel | Natural Gas, Propane |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 25 kW |
| Standby kVA | 31 |
| Prime power | 25 kW |
| Controller | Engine Control Module |
| Oil capacity | 4.0 L |
| Phase | 60 Hertz |
| Battery voltage | 12 V |
| Coolant capacity | 11 L |
Engine
| Oil capacity | 4.0 L |
|---|---|
| Coolant capacity | 11.0 L |
| Aspiration | Turbocharged |
Maintenance & consumables
for the Cummins/Onan LRG-423 (Turbocharged)| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | — | 90 hr | |||
| Fuel filter | — | 90 hr | |||
| Oil filter | ENGINE OIL FILTER | LS1169s | Amazon eBay | ||
| Battery | — | ||||
| Belt | — | 90 hr | |||
| Coolant | — | ||||
| Coolant filter | — | ||||
| Oil | API viscosity grade for the temperature conditions | — | 200 hr | ||
| Spark plug | — | 360 hr |
Common questions
What size generator is the Cummins/Onan 25 GEAF?
The Cummins/Onan 25 GEAF is rated 25 kW standby (31.25 kVA).
What engine does the Cummins/Onan 25 GEAF use?
The Cummins/Onan 25 GEAF is powered by the Cummins/Onan LRG-423 (Turbocharged) engine.
What fuel does the Cummins/Onan 25 GEAF use?
The Cummins/Onan 25 GEAF runs on Natural Gas, Propane.
What's the oil capacity on a Cummins/Onan 25 GEAF?
The Cummins/Onan LRG-423 (Turbocharged) engine in the Cummins/Onan 25 GEAF has an oil capacity of 4.0 liters.
What is the coolant capacity of the Cummins/Onan 25 GEAF?
The Cummins/Onan 25 GEAF cooling system holds 11 liters (2.9 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.
What oil filter does the Cummins/Onan 25 GEAF use?
The Cummins/Onan 25 GEAF uses oil filter part number LS1169s.
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| PRE HET/LOP lamp lights. Engine continues to operate — engine has begun to overheat and engine temperature has risen to approximately 205°F (97°C) or coolant level is low | Engine has begun to overheat and engine temperature has risen to approximately 205°F (97°C) or coolant level is low | If generator is powering non-critical and critical loads and cannot be shut down: reduce load if possible by turning off non-critical loads; check air inlets and outlets and remove any obstructions to airflow |
| PRE HET/LOP lamp lights. Engine continues to operate — engine oil pressure has dropped to 30 psi (207 kPa) | Engine oil pressure has dropped to 30 psi (207 kPa) | If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow step 4; if engine can be stopped follow procedure in Steps 3 and 4 |
| HI ENG TEMP lamp lights. Engine shuts down — engine has overheated (engine temperature has risen above 215°F/102°C) or coolant level is low | Engine has overheated (engine temperature has risen above 215°F/102°C) or coolant level is low | Allow engine to cool down completely before proceeding with the following checks: check coolant level and replenish if low, look for possible coolant leakage points and repair if necessary; check for obstructions to cooling airflow and correct as necessary; check for a slipping fan belt and tighten if loose; reset control and restart after locating and correcting problem; contact an authorized service center if none of the above |
| LO OIL PRES lamp lights. Engine shuts down — engine oil pressure has dropped to 25 psi (172 kPa) | Engine oil pressure has dropped to 25 psi (172 kPa) | Check oil level, lines and filters; if oil system is OK but oil level is low, replenish; reset control and restart; contact an authorized service center if oil pressure is not in the range of 40 to 65 psi (275 to 448 kPa) |
| OVERCRANK lamp lights and engine stops cranking — possible fuel system problem | Possible fuel system problem | Check for empty fuel tank (LPG Vapor), fuel or leaks, or plugged fuel lines and correct as required; check for dirty fuel filter and replace if necessary (see Maintenance section); check for dirty or plugged air filter and replace if necessary (see Maintenance section); reset the control and restart after correcting the problem; contact an authorized service center for service if none of the above |
| Engine runs, shuts down, and LO OIL PRES lamp lights | See step 5 (OVERCRANK): check for empty fuel tank (LPG Vapor), fuel or leaks, or plugged fuel lines and correct as required; check for dirty fuel filter and replace if necessary; check for dirty or plugged air filter and replace if necessary; reset the control and restart after correcting the problem; contact an authorized service center for service if none of the above |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan 25 GEAF troubleshooting guide (49 entries) →
Parts
3| Part # | Description | Qty | System | |
|---|---|---|---|---|
| FS-1176s | Crankcase Oil and Filter | Gas mixer | Amazon eBay | |
| LS1169s | FILTER | 1 | Oil filter | Amazon eBay |
| D1400 | DONALDSONS D1400 SOLVENT | Service part / kit | Amazon eBay FridayParts $48.99 |
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
This page was generated from the 2 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.