Cummins/Onan — Fuel Lines
Installation · fuel system
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
- Leakage of gasoline in or around compartment is a definite hazard.
- Because of fire hazard, do not tie electrical wiring to fuel line.
Procedure
- Follow chassis manufacturer's detailed installation instructions for all connections to vehicle fuel system.
- Install approved flexible non-metallic and non-organic fuel line between vehicle fuel system and engine to absorb vibration.
- Use seamless steel tubing and flared connections for long runs between fuel tank and flexible connector.
- Run fuel lines at top level of tank to a point as close to engine as possible.
- Keep fuel lines away from hot engine or exhaust areas to reduce chance of vapor lock.
- Flexible line must be long enough to allow for 4 inches of set movement.
- Install lines so they are accessible and protected from damage.
- Use metal straps without sharp edges to secure fuel lines.
- Do not run fuel line in conjunction with electrical wiring.
Specs & values
- Flexible line must allow 4 inches of set movement
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.