Cummins/Onan — Generator Set Disassembly
Repair & overhaul
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan HDKA
Before you start
- Disconnect battery cables, negative lead first; generator set components are heavy - use appropriate lifting techniques.
Procedure
- Remove the set from the vehicle and place it on a sturdy work bench.
- Remove the AC control box cover and disconnect all stator leads; mark leads with tape.
- Remove the bonding strap between the stator assembly and the drip pan.
- Remove the two bolts through the rear generator set mounts.
- Prop up the engine-to-generator set adapter with a wooden block and remove the two rubber vibration isolators.
- Remove the end bell cover and disconnect F1 (outer) and F2 (inner) lead wires from the brush holder.
- Pull each brush away from the commutator rings and insert stiff wire into the brush holder hole.
- Remove four nuts and lock washers from the stud bolts; remove the end bell cover and pry the end bell free.
- Pull the stator/wrapper assembly with the control boxes off the rotor and set aside.
- Remove the four bolts holding the adapter and fan guard to the engine-to-generator adapter.
- Loosen the six rotor drive disk bolts in an alternating pattern.
- Pull the rotor, fan and drive disk assembly off the flywheel.
Tools required
- Wooden block approximately 3.5 inches wide Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Full service-parts list: Cummins/Onan HDKA →
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.