Cummins/Onan — Cleaning Crankcase Breather Valve
Maintenance
From a Cummins/Onan service manual covering: 0.6MAJ, 1.0MAJ, 1.5MAJ, 1.5MAJ-224R, 1.5MAJ-232R, 2.5MAJ. Check it applies to your exact model before use.
Applies to: Cummins/Onan 2.5MAJ
Procedure
- Every 100 hours or sooner, remove breather tube.
- Wash valve (5/16 inch ball) in a solvent.
- Check breather tube for security and leaks.
Tools required
- solvent Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 5/16 inch ball
- 100 hours
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.