Cummins/Onan — Flash the exciter field
Repair & overhaul
From a Cummins/Onan service manual covering: 4A2.3, 6A3.4-GS, 6AT3.4-GS, DL4, DL6, QSA3, QSA4, QSA6. Check it applies to your exact model before use.
Applies to: Cummins/Onan DGAB, Cummins/Onan DGAC, Cummins/Onan DGAD, Cummins/Onan DGAE, Cummins/Onan DL4, Cummins/Onan DL6
Before you start
- Incorrect flashing procedure can damage the voltage regulator.
Procedure
- Assemble 12-volt battery, 10-ampere fuse, momentary-on switch, and 12-ampere diode.
- Connect positive lead to voltage regulator terminal 9 and negative to terminal 10.
- Start genset and operate at normal speed.
- Close switch until output voltage builds, but not longer than five seconds.
- Check output voltage, shut down, restart, and verify voltage builds without flashing.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Do not keep excitation circuitry connected longer than five seconds.
Full service-parts list: Cummins/Onan DGAB →, Cummins/Onan DGAC →, Cummins/Onan DGAD →, Cummins/Onan DGAE →, Cummins/Onan DL6 →
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.