370 ISL fuel line: Rubber or Steel

[Golden Gopher]

Does anyone know what the fuel line is constructed of?

This will help in my discussion with the repair shop for the small diesel leak on my DSDP.

Thanks!

[MnTom]

It depends on where the particular line is located. There are both steel and rubber on your coach.

[Gary RVRoamer]

The fuel system is provided by the chassis builder, not Cummins. It may vary by chassis model.

[Golden Gopher]

The leak was found to be the lift pump.

Found Conntryfit and Dutchstar411 posts on tightening the 3 bolts that hold the pump.

Problem looks to be ULSD in pre2007 Cummins engines causing gasket shrinkage.

This is not unlike ethanol causing same issue in gas engines.

Bolts were tightened, leak has stopped, we are good to go!

Thanks to all!

[Smitty77]

Glad the snugging up of the bolts worked for you...!
G

[JC2]

Originally Posted by Golden Gopher

The leak was found to be the lift pump.

Found Conntryfit and Dutchstar411 posts on tightening the 3 bolts that hold the pump.

Problem looks to be ULSD in pre2007 Cummins engines causing gasket shrinkage.

This is not unlike ethanol causing same issue in gas engines.

Bolts were tightened, leak has stopped, we are good to go!

Thanks to all!

Maybe, maybe not. ULSD apparently did/does not play well will the gasket material for lift pumps back in the general time frame mentioned. Ours was leaking also but not from loose bolts. We had the lift pump replaced with a new/improved version() several years ago and have had no problems since. Keep an eye on it for possible further leakage cropping up.