Cummins/Onan 205AJ — Timing the ignition
Adjustments · magneto
For the Cummins/Onan 205AJ, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan AJ series
Procedure
- See that point gap is properly adjusted.
- Install flywheel loosely with key in place.
- Turn flywheel in rotation direction until mark aligns with proper degree mark on gear cover.
- Points should just separate at this point.
- If not, remove flywheel and loosen magneto backplate mounting screws slightly.
- If points separate too soon, shift backplate clockwise; if too late, counterclockwise.
- Retighten screws and recheck; ensure flywheel key is in place.
Specs & values
- Ignition timing advance: 25° B.T.C. above 1800 rpm; 19° B.T.C. for 1800 rpm plants
Full service-parts list: Cummins/Onan AJ series →
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.