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Cummins lift pump leaking

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Phil And Carol Upham:
A friend owns an 03 Winnie with a Cummins, I am not certain of the size.  He reported a slight leak in his Lift Pump.  He replaced it for about $700 labor and parts.  We have the Cat 330 and I asked him if it was the same for us.  Is this something all of us older motorhomes are going to have to repair/replace due to the new fuel?  Here is what he said:

"I would assume that a CAT has a similar setup, but not sure. From what I understand of it, the lift/transfer pump runs for a few minutes at startup to “prime” the engine. Then it shuts down. So it apparently does not have potential to leak a lot, or at least for a long time.  But apparently when it gets bad it can suck air into the fuel system, which is a potential bad scene.  The seals and/or gasket between the pump & block apparently dries out and shrinks from the lower lubricity in ULSD … only on engines that have previously run LSD."

Thanks,
Phil

Richard And Babs Ames:
http://www.enginebuildermag.com/Article/4720/cummins_lift_pump_leakage_due_to_ultra_low_sulfur_diesel_fuel.aspx

Here is an article about lift pump leakage and is seems to affect only certain Cummins engines. It is related to the seal material. CAT does not seem affected to date.

Phil And Carol Upham:
Thank you!
Phil

Joel Ashley:
I've heard the claim that ULSD, by way of lower sulfur content, has lost its lubricity.  But others argue against that notion, and I've come to believe ULSD actually has no less lubricity than its predecessor, so any concerns in that dept. are misplaced.

Bill Sprague:
After we owned our Beaver for awhile I was shocked to learn it was supposed to have a Cat!  We have a Cummins and the lift pump seal did develop a leak after running about 3,000 gallows of old diesel followed by about 2,000 gallons of ULSD.  We were in the Maritimes of eastern Canada.  Went to the nearest truck shop with a Cummins sign.  Cummins would not honor the warrantly unless the shop replaced the whole assembly.  The shop thought that changing the seal would fix it.  Cummins sent the new assembly, including pump and mounting bracket.  It was in a difficult location and took the shop about 5 hours to get the old one out and the new one it.  Cummins paid the entire bill.  I suspect Cummins wanted it back as a unit to analize the failure.  I'm pretty sure that most of it is history.  ULSD has been all you can get for long enough that any seals scheduled to fail would have by now.

Does anybody know why 2004 Montereys didn't get a CAT?  What other years and models were deprived of their heritage?

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