Cummins/Onan 6GO — Ignition Timing
Adjustments · Distributor / ignition
For the Cummins/Onan 6GO, from the Cummins/Onan operator's manual.
Applies to: Continental Red Seal Y91-273 or Y91-264 engine
Before you start
- A continuous ping indicates the timing must be retarded.
Procedure
- Set the distributor contact points to 0.020 in gap at full separation.
- Remove the flywheel inspection hole cover and turn the engine until the No. 1 piston is coming up on the compression stroke.
- Slowly crank until the flywheel mark is on center in the inspection hole.
- Distributor rotor should point to the cap tower for the No. 1 spark plug wire and the points should just separate.
- If the rotor points to the No. 4 tower, remove the distributor, lift the drive shaft in the cylinder head and turn it one half turn.
- Start the plant and allow it to reach operating temperature, then test the spark advance by applying full electrical load.
- Slow the engine by pulling on the governor arm, then release and allow sudden acceleration; one or two pings should be heard.
- Advance or retard the timing by loosening the distributor clamp and turning the distributor body; retighten the clamp screw.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 0.020 in point gap
- Keep spark advanced as far as possible without pinging
Source: Cummins/Onan operator'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.