Cummins/Onan — Mica undercutting
Maintenance · commutator
From a Cummins/Onan owner's manual covering: 10CW-150R, LOCW-150 R/, LOCW-3R/12 F. Check it applies to your exact model before use.
Applies to: Cummins/Onan 10CW-150R, Cummins/Onan Spec A, Cummins/Onan Spec B, Cummins/Onan Spec C, Cummins/Onan Spec D, Cummins/Onan Spec E, Cummins/Onan Spec F, Cummins/Onan Spec G
Before you start
- Avoid scratching the surface.
Procedure
- Remove brush springs and pull all brushes out of guides.
- Tag and disconnect leads; remove end bell.
- Use mica undercutting tool or hacksaw blade to cut mica between commutator bars to 1/32 inch depth.
- Avoid scratching commutator surface.
- Remove burrs and clean spaces between bars free of metallic particles.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 1/32 inch depth
Full service-parts list: Cummins/Onan 10CW-150R →, Cummins/Onan Spec A →, Cummins/Onan Spec B →, Cummins/Onan Spec C →, Cummins/Onan Spec D →, Cummins/Onan Spec E →, Cummins/Onan Spec F →, Cummins/Onan Spec G →
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.