Cummins/Onan — Replacing Diodes
Repair & overhaul · Exciter rectifier bridge
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan DFAA, Cummins/Onan DFAB, Cummins/Onan DFAC, Cummins/Onan DFBF, Cummins/Onan DFCB, Cummins/Onan DFCC, Cummins/Onan DFCE, Cummins/Onan DFE
Procedure
- Make sure the replacement diode is of the correct polarity.
- Disconnect the pigtail; unscrew the old diode.
- Apply heat-sink compound under the head; keep off threads.
- Torque diodes to 36 to 42 in-lbs (4 to 4.8 Nm).
- Torque pigtail terminals to 24 in-lbs (2.7 Nm).
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Diodes 36 to 42 in-lbs (4 to 4.8 Nm)
- Pigtail terminals 24 in-lbs (2.7 Nm)
Full service-parts list: Cummins/Onan DFBF →, Cummins/Onan DFCC →, Cummins/Onan DFCE →, Cummins/Onan DFE →
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.