Cummins/Onan — Compartment
Installation · generator set compartment
From a Cummins/Onan service manual covering: 3.0 AJ, 4.0 BFA, 5.0 BGA, 6.5 NH, T-012. Check it applies to your exact model before use.
Applies to: Cummins/Onan 4.0 BFA
Before you start
- Do not use flammable material directly above or around the generator set compartment.
- Be sure drain hole is not directly above muffler to prevent fire hazard.
- Separate installation area or compartment from living quarters by a vapor-tight wall to prevent entrance of noxious fumes to interior.
Procedure
- Install generator set in its own compartment separated from living quarters and fuel supply by a vapor-tight wall.
- Line compartment or separate set from living quarters with fire barrier of galvanized steel (22 gauge minimum) or equivalent noncombustible material.
- Seal compartment vapor tight to prevent noxious fumes entering motor home interior.
- Leave clearance as specified in individual installation guide; maintain one inch minimum for generator cooling air inlets on generator end.
- Compartment bottom must have minimal openings; use sheet metal base plate or plywood covered with sheet metal.
- Equip base with oil drain hole to outside of compartment, not directly above muffler.
- Do not use absorbent material on inside compartment floor.
- Construct compartment floor to prevent accumulation of oil, fuel or water in corners; use 1/2 inch diameter hole near each corner or other suitable drainage.
Specs & values
- 22 gauge minimum galvanized steel fire barrier
- 1 inch minimum clearance for cooling air inlet
- 1/2 inch diameter drain hole near each corner
Full service-parts list: Cummins/Onan 4.0 BFA →
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.