Cummins/Onan — Ignition Timing Check and Adjustment
Adjustments · magneto
From a Cummins/Onan service manual covering: 10C, 10CW, 10CW-150R, 5CW, 6CW-51R, 7.5C, 7.5CW, 9CW. Check it applies to your exact model before use.
Applies to: Cummins/Onan 10CW-150R
Procedure
- Remove end cap from magneto.
- Adjust magneto breaker points to a gap of .015-inch at full separation.
- Remove air cover from right hand cylinder to expose flywheel housing timing hole.
- Slowly turn engine until IGN timing mark centers in timing hole; a sharp click should be heard.
- If click occurs before or after mark, loosen two magneto mounting screws and turn magneto slightly.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Magneto breaker points gap .015 inch
Full service-parts list: Cummins/Onan 10CW-150R →
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.