Cummins/Onan — Crankcase Breather Service (DFW, DFY)
Maintenance
From a Cummins/Onan owner's manual covering: 450 DFW, 450 DM, 500 DM, 600 DFY, 750 DFZ. Check it applies to your exact model before use.
Applies to: Cummins/Onan 450 DFW, Cummins/Onan 450 DM, Cummins/Onan 500 DM, Cummins/Onan 600 DFY, Cummins/Onan 750 DFZ, Cummins/Onan VTA-28-GI engine, Cummins/Onan VT-28-G engine, Cummins/Onan VTA28-G2 engine, Cummins/Onan KTA-38-GI engine
Procedure
- Remove wing nut, flat washer and rubber washer; lift cover away from filter assembly.
- Lift out breather element, vapor element and gasket.
- Clean all parts with approved solvent; dry with compressed air (30 psi maximum OSHA).
- Inspect all parts, replace if necessary.
- Reassemble filter assembly, replace cover and secure.
Tools required
- compressed air Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Air pressure 30 psi maximum
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.