Cummins/Onan 627.20199 — Tappet Adjustment
Adjustments · valve train
For the Cummins/Onan 627.20199, from the Cummins/Onan owner's manual.
Applies to: Craftsman 627.20199
Procedure
- Remove valve covers.
- Facing flywheel, slowly crank engine until left-hand intake valve opens and closes.
- Continue about 1/4 turn until flywheel mark and TC mark align.
- Check each valve clearance with thinner gauge passing freely and thicker gauge not.
- Turn adjustable self-locking screw to correct clearance.
- To adjust right-hand cylinder, crank engine one revolution and align marks again.
- Repeat adjustment procedure for right-hand cylinder valves.
Tools required
- Feeler gauge Amazon
- Standard automotive-type wrench
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Intake 0.006 to 0.008 in
- Exhaust 0.015 to 0.017 in
Full service-parts list: Craftsman 627.20199 →
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.