Cummins/Onan — Cylinder Honing Procedure
Repair & overhaul · Cylinder block
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan CCK engine
Before you start
- Do not use solvent or gasoline for cleaning.
Procedure
- Remove stock to 0.002 in less than finished bore with coarse hone (100 grit).
- Anchor block; use drill at 250 to 450 rpm.
- Lower hone into cylinder until it protrudes 1/2 to 3/4 in past end.
- Rotate adjusting nut until stones contact narrowest point.
- Loosen nut until hone turns by hand.
- Move hone up and down about 40 cycles per minute.
- Change to fine stones (300 grit) when within 0.002 in.
- Clean block thoroughly.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Crosshatch angle 23 degrees
- Finish 300 grit
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.