Cummins/Onan — Crankcase Breather Service
Maintenance · Crankcase breather (turbocharged engines)
From a Cummins/Onan owner's manual covering: 4A2.3, 4A2.3-GS/GC, 6A3.4-GS/GC-1, 6A3.4-GS/GC-2, 6AT3.4-GS/GC, ES-1788. Check it applies to your exact model before use.
Applies to: Cummins/Onan ES-1788, Cummins/Onan 4A2.3 engine
Before you start
- Overtightening of the clamp will tear breather cap.
Procedure
- Remove breather cap and lift out breather element.
- Clean breather cap and element in cleaning solvent.
- Dry thoroughly with low pressure air, under 35 psi (241 kPa).
- Install clean or new breather element in valve cover; do not pack element into valve cover.
- Install clamp, breather cap, and connect breather tube.
Specs & values
- Air pressure: under 35 psi (241 kPa)
Full service-parts list: Cummins/Onan ES-1788 →
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.