Cummins/Onan — Brush Removal and Replacement (Power Drawer)
Maintenance · Power Drawer generator brushes
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan MCCK
Before you start
- Always replace brushes as a set; never use a substitute brush.
Procedure
- Remove the plastic end bell screens to reach the brushes.
- Measure brush wear by inserting a small, narrow scale into the top of the brush block.
- Remove and tag the wires connected to the brush blocks.
- Remove the brush blocks and lift them out of the end bell.
- Pull the brushes and springs out from the bottom of the brush block and clean the block.
- Install new brushes as a set; brush blocks are stamped BRG END facing the bearing end.
Tools required
- Small narrow scale Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Tighten brush block screws to 40 to 70 in.lb or 4 to 6 ft.lb (5 to 8 N·m)
- Maximum brush wear limit one inch (25 mm)
Full service-parts list: Cummins/Onan MCCK →
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.