Cummins/Onan — Governor Cup Service
Repair & overhaul
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan MCCK
Before you start
- Camshaft center pin cannot be pulled outward nor removed without damage.
Procedure
- Remove snap ring from camshaft center pin.
- Catch flyballs while sliding cup off.
- Replace any flyball that is grooved or has a flat spot.
- If arms of ball spacer are worn or damaged, replace entire timing gear set.
- Governor cup must spin freely on camshaft center pin without excessive looseness or wobble.
- If race surface of cup is grooved or rough, replace it.
- When installing, tilt engine so gear is up, put flyballs in place, install cup and snap ring on center pin.
- Hold cup against flyballs when measuring; camshaft center pin extends 3/4 inch from end of camshaft.
- This provides in and out travel distance of 7/32 inch for governor cup.
- If distance is less, remove center pin and press new pin in only required amount; otherwise grind off hub of cup as required.
Specs & values
- Camshaft center pin extension: 3/4 inch
- Governor cup travel: 7/32 inch
Full service-parts list: Cummins/Onan MCCK →
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.