Cummins/Onan — Brush Examination, Removal and Installation
Maintenance · generator brushes
From a Cummins/Onan owner's manual covering: 150UK2XN1A, 150UK5XN1A, 150UK6XN1A. Check it applies to your exact model before use.
Browse Cummins/Onan generators & specs →
Before you start
- Do not attempt to remove brush without first removing its spring and bracket.
- Never bend a spring back over its bracket.
Procedure
- Remove the exciter cover to examine brushes, brush springs, and slip rings.
- Remove screws from the left side of the exciter plate and swing the assembly outward.
- Openings in the alternator end bell permit access to the brush rig.
- To remove brush, press spring holder down and out as shown.
- Install brushes with bevelled top slanting down toward spring holder.
- Replace brushes when worn to approximately 1/2 inch long or when top of brush is below a point midway between outer and inner end of its guide.
- Do not attempt to remove the brush without first removing its spring and bracket.
- Never bend a spring back over its bracket.
Specs & values
- Replace brushes when worn to approximately 1/2 inch long.
Source: Cummins/Onan owner's 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.