The Cummins/Onan 4B3.9 engine line groups 4 variant designations. Parts and fitment are pooled here so a cross-reference found on one variant surfaces for the whole family.
| Part # | Description | Category |
|---|---|---|
| 982-0200 | Air Filter | Air filter |
| 300-3606 | Voltage Regulator Installation (PMG-Excited Generators), Rev. P | Avr |
| 300-3607 | Voltage Regulator Installation (Self-Excited Generators), Rev. G | Avr |
| 220-4289-31 | Main stator assembly (broad range generators) | Service part / kit |
| 220-4289-32 | Main stator assembly (broad range generators) | Service part / kit |
| 220-4289-33 | Main stator assembly (broad range generators) | Service part / kit |
| 220-4289-34 | Main stator assembly (broad range generators) | Service part / kit |
| 220-4289-35 | Main stator assembly (broad range generators) | Service part / kit |
| 220-4298-31 | Main stator assembly | Service part / kit |
| 220-4298-32 | Main stator assembly | Service part / kit |
| 220-4298-33 | Main stator assembly | Service part / kit |
| 220-4298-34 | Main stator assembly | Service part / kit |
| 220-4298-35 | Main stator assembly | Service part / kit |
| 220-4298-36 | Main stator assembly | Service part / kit |
| 300-4111 | Auxiliary Relay Board (ARB), Rev. E | Service part / kit |
| 319-0969 | QS-Series Power Distribution Panel Wiring, Rev. G | Service part / kit |
| 612-6487 | 7-Light DC Control Wiring Diagram, Sh 1 and 2 of 2, Rev. V | Service part / kit |
| 612-6488 | 12-Light DC Control Wiring Diagram, Sh 1 and 2 of 2, Rev. W | Service part / kit |
| 612-6489 | AC Control Wiring Diagram (Without Meters), Rev. S, modified 6/2001 | Service part / kit |
| 612-6490 | AC Control Wiring Diagram (With Meters), Rev. ZB, modified 1/2002 | Service part / kit |
| 625-2164 | Generator Reconnection Diagrams, Sh 1 and 2 of 2, Rev. K | Service part / kit |
| 625-2256 | QS-Series Generator Connections When The Voltage Selector Switch Is Provided, Rev. B | Service part / kit |
| 965-0520 | Cooling Fan | Service part / kit |
| 625-2141 | Day Tank Pump Control Wiring, Rev. P | Pump |
Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.