The Cummins/Onan 4BTA3.9-G2 is a 3.9 L 4-cylinder after-cooled, turbo-charged engine rated at 1500 rpm. It powers generator sets from Cummins/Onan, including the C55 D5. It holds 11 L (2.9 gal) of oil and 8 L (2.1 gal) of coolant.
Part of the Cummins/Onan 4BTA3.9 engine family — 4 variants share parts & fitment.
| Oil capacity | 11.0 L |
|---|---|
| Coolant capacity | 8.0 L |
| Displacement | 3.9 L |
| Cylinders | 4 |
| Aspiration | After-cooled, turbo-charged |
| Rated speed | 1500 rpm |
| Part # | Description | Category |
|---|---|---|
| 012046 | Air Cleaner | air_filter |
| 012040 | Battery | battery |
| 012041 | Fan Belt | belt |
| 012045 | Coolant Overflow Reservoir | coolant_filter |
| 2.4L | Engine | engine |
| 012044 | Oil Drain Hose | fluid |
| 012042 | Oil Filter | oil_filter |
| 012043 | Oil Fill Cap | oil_filter |
| A046K020 | Oil Filter | oil_filter |
| 0L2090-C | 60 kW (2.4 L) | other_service |
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 4BTA3.9-G2 engine has an oil capacity of 11.0 liters.
The Cummins/Onan 4BTA3.9-G2 has a displacement of 3.9 liters with 4 cylinders.
The Cummins/Onan 4BTA3.9-G2 powers 1 generator set(s), including Cummins/Onan C55 D5.