Chrisreyn

hey guys, usually post in the First Gen forums, but need some help with a second gen truck.
My son-in-law recently purchased a 1996 3500 4WD...
He was going down the road yesterday and it started cutting out on him, wouldn't stay running at an idle.
he had it towed to a shop and they have advised him it is the lift pump and quoted him over $300 for the R&R.

How different is the 2nd Gen pump from the first gen pump?
Wheres the cheapest place to get one and what else might cause this sort of issue?
I have already advised him to replace the fuel filter first.
how difficult is replacing the pump on a 2nd Gen?
any info will be appreciated!!!

shortround

Three (?) bolts and a connector plus a couple of line connections.
NAPA pumps seem to be good(fingers crossed). ~$100 depending on discount.
Seems odd to run at speed but not idle.
Guy at work had symptoms like that and it was the crankshaft position sensor (over by the starter) $35 and he's running strong.

Chrisreyn

ok, I mis-spoke... it cut out and wouldnt stay running and now wont start at all..
just got off the phone with the duaghter, and he hasnt even tryed bleeding the lines yet, after replacing the FF yesterday, so this thread may have been a little premature.
to me it sounds like his FF clogged or gelled and now he just needs to bleed the lines.. I guess he spoke to a shop on the phone who told him it was probably the LP and no-one has actually looked at it yet.

MikeR

The 94-98 lift pump is located in the same place as your 1st gen.
You can buy them for about 80-85 bucks directly from Cummins, and you need two mounting gaskets. They are easy for DIY.

As far as you needing it? maybe, probably. A fuel pressure test would show if you need it, or an overflow valve. But I would replace the overflow valve too just because of age and wear. And don't forget to reset your idle speed. The idle stop linkage is worn on all of them by now, and need to be re-adjusted anyway.
You could just start with a new fuel filter and see what happens.

Shortround,
12 valve motors don't depend on a crank sensor for anything. That's a 24 valve thing.

patdaly

Make sure the P7100 pump fuel shutoff lever is up....... Could be the shutoff relay or solenoid also!