Cummins ISM in Monaco coach

[Hokiefyd]

Thanks guys. I will suggest Blackstone (they do the UOAs, I don't send them in). I will also suggest the injector pump. I'll report back if/when they find the problem.

 

[slammds15]

If the engine seems to be running smoothly/well and has no strange noise or excessive fuel consumption I would be willing to bet the pump is the culprit. The pump would have to be removed and properly pressure tested and inspected for a proper diagnosis. As long as fuel is found in the oil... Let us know how you make out.

 

[varmint]

I would have the fuel transfer pump check first. These have a
history of leaking into sump when seals go from using ULSD fuel. I think this is an ISL engine?

 

[varmint]

sorry wrong answer.I was thinking of something else.

 

[Hokiefyd]

Dad said it was diagnosed as a bad high pressure pump. Can the pump be rebuilt or have the seals replaced, or is entire pump replacement the only option? That pump is mighty expensive!

Thanks for the help so far!