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 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. | Indicates engine has begun to overheat and engine temperature has risen to approximately 205°F (97°C) or coolant level is low. | A. Reduce load if possible by turning off non-critical loads. b. Check cooling air inlets and outlets and remove any obstructions to airflow. |
| HI ENG TEMP lamp lights. Engine shuts down. | Indicates engine has overheated (engine temperature has risen above 215°F/102°C) or coolant level is low. | A. Check coolant level and replenish if low. Look for possible coolant leakage points and repair if necessary. b. Check for obstructions to cooling airflow and correct as necessary. c. Check for a slipping fan belt and tighten if loose. d. 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. | Indicates engine oil pressure has dropped to 14 psi (97 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. | Indicates possible fuel system problem. | A. Check for empty fuel tank (LPG Vapor), fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace (if installed on fuel line). c. Check for dirty or plugged air filter and replace if necessary (see Maintenance section). d. Reset the control and restart after correcting the problem. Contact an authorized service center for service if none of the above. |
| Engine runs and then shuts down, OVERSPEED lamp lights. | Contact an authorized service center for service. | |
| SWITCH OFF lamp flashes. | Indicates Run/Stop/Remote switch is in the Stop position which will prevent automatic starting if an automatic transfer switch is used. Move the Run/Stop/Remote switch to the Remote position for automatic starting. |
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 (26 entries) →
Parts
4| Part # | Description | Qty | System | |
|---|---|---|---|---|
| FS-1176s | Crankcase Oil and Filter | Gas mixer | Amazon eBay | |
| LS1169s | FILTER | 1 | Oil filter | Amazon eBay |
| 928-0606 | 1 | Service part / kit | 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.