The Cummins/Onan QSX15-G9 is a 15 L 6-cylinder turbocharged, air to water aftercooled engine rated at 1800 rpm, producing up to 24.1 kW. It powers generator sets from Cummins/Onan and MQ Power, including the C450D6, C500D6, DFE and CG500C2. It holds 91 L (24.0 gal) of oil and 24 L (6.3 gal) of coolant.
Also known as: Cummins QSX15-G9
Part of the Cummins/Onan QSX15 engine family — 8 variants share parts & fitment.
| Oil capacity | 91.0 L |
|---|---|
| Coolant capacity | 24.0 L |
| Displacement | 15.0 L |
| Cylinders | 6 |
| Aspiration | Turbocharged, Air to Water Aftercooled |
| Rated speed | 1800 rpm |
| Gross power | 24 kW |
Shared across brands: Cummins/Onan, MQ Power
| Code | Meaning |
|---|---|
| 1471 | Over Current |
| 2342 | Too Long in Idle |
| 2968 | AVR Fault |
| 2972 | Field Overload |
| 441 | Low Battery Voltage |
| 442 | High Battery Voltage |
| 2331 | Low AC Voltage |
| 2358 | High AC Voltage |
| 427 | CAN Datalink Lost Message |
| 781 | CAN Datalink Lost Messages |
| 1245 | CAN - Engine Shutdown |
| 1246 | CAN - Unknown Engine Fault |
| 1247 | CAN - Engine Unannounced Fault |
| 1248 | CAN - Engine Warning Fault |
Fault codes and symptom→remedy steps extracted from this engine’s service/owner documentation; verify against the official manual before servicing.
| Part # | Description | Category |
|---|---|---|
| AF25544 | Recommended air cleaner element - (heavy duty) primary element | air_filter |
| AF25545 | Recommended air cleaner element - (heavy duty) secondary element | air_filter |
| 19802521 | ECM Dataplate | ecm |
| 3331096 | Cummins, Part No. 3331096 | fuel_filter |
| FS1007 | Fleetguard® Nelson®, Part No. FS1007 | fuel_filter |
| M-4376220 | Upper Gasket Set | gasket |
| M-4376221 | Lower Gasket Set | gasket |
| 3406810 | Combination Full-Flow/Bypass Lubricating Oil Filter Cummins Part No. 3406810 | oil_filter |
| 17200015 | Engine Shutdown | other_service |
| 17690172 | Engine Braking System | other_service |
| 17800006 | Engine Model | other_service |
| 3163156 | Service cable for InPower™ | other_service |
| 3822735 | Plastic bead media | other_service |
| 3886301 | InPower™ electronic service tool | other_service |
| 956-0120 | other_service | |
| 956-0220 | other_service | |
| 960-0132 | other_service | |
| 960-0174B | other_service | |
| TB3-5 | Generator Set Control Panel Terminal Block | other_service |
| TB3-6 | Generator Set Control Panel Terminal Block | other_service |
| ol204vt | Torque Peak | other_service |
| M-5473087 | Piston Kit | piston_kit |
| M-5484414 | Piston Pin | piston_pin |
| 3375044 | Torque Wrench | tool |
| 3375049 | oil filter wrench | tool |
| 3376807 | Coolant Filter Wrench | tool |
Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.
The Cummins/Onan QSX15-G9 engine has an oil capacity of 91.0 liters.
The Cummins/Onan QSX15-G9 has a displacement of 15.0 liters with 6 cylinders.
The Cummins/Onan QSX15-G9 powers 5 generator set(s), including Cummins/Onan C450D6, Cummins/Onan C500D6, Cummins/Onan DFE, MQ Power CG500C2, MQ Power EGC-500C.