Lift Pump?

[Farmboy]

I have been having random starting issues with my truck.. most of the time you hit the key and as quick as you can let go of the key again, it is started.. However, lately (and only every now and then) it will start and then immediatly stall.. almost like it is running out of fuel. Start it again and stab the throttle it will snap out of it.. When it is doing this it will idle very low until it gets warmed up and then it seems to idle just fine... Also even when it does this... seems to have great power still while pulling a trailer weighted down to about 10K

Does this sound like a lift pump? if not, does anyone have any other ideas?

[RCCUMMINS89]

Possibly, what I mean is.... It sounds like it is sucking air somewhere and fuel is draining back. Are you leaking fuel around any of your inj. lines or feed lines that you can see?

[Farmboy]

That is a good point. I will look. how about by the fuel filter? would that do it.. I think I remember seeing some moisture there..

[RCCUMMINS89]

Yes that could def. do it.

[PToombs]

If you saw moisture near the fiter, check the fuel heater. The o-ring is known to go bad and that will let air in. Maybe you can clean it with brake cleaner and pump the primer and see if it leaks. If not, clean it and run the truck.

[Farmboy]

Well I didn't get a chance to really get a close look at the fuel filter but I did notice the valve cover gaskets are weeping some... We were working on the brake controller wiring last night and I forgot to get a close look at the fuel filter. I will look at it a little closer tonight..

on another note, I believe this is the original lift pump on this truck so even if this is not the problem I probably should look into replacing it. What would be the best replacement, mechanical or electrical?

[Diesel]

I got a new napa mechanical. I think it's nice to keep these engines as mechanical as possible.

[Farmboy]

Just a stock, direct replacement from NAPA?

[Mark Nixon]

The absolute LAST pump I'd put on there is what's on there now.
If you're going to replace it with anything beside an electric one (recommended), do it with a LPPLP conversion, much more reliable and well worth the cost for the longevity.

The stock replacement aftermarket stuff is pure garbage, not even worth the effort to call on it, IMHO.

Mark.

[RCCUMMINS89]

What do you like with an electric? Personally, the one thing I like about our trucks is they don't have the electric bs that the new ones have.

But I agree go with a lpplp.....

[Mark Nixon]

What do you like with an electric? Personally, the one thing I like about our trucks is they don't have the electric bs that the new ones have.

An electric has literally ZERO chance of internal leakage allowing air into the system, unlike the stock 1st gen diaphragm types will do.
There's also the fact that, if need be, priming the supply side is a switch away, which we fat guys can really appreciate.

In reality, cheap electrics are competitively priced with even low-priced mechanicals, which means the cost to carry a spare is negligible, and usually about the same hassle to swap alongside the road as a mechanical, easier in some cases.

I've been running a Pro Comp Black on the Car Hauler for 5 years, probably the cheapest, most dependable low-end vane pump I have ever ran across.
No, at a purchase price of $60 (they are cheaper now, even), it's not the holy grail, but 5 years of inconsistent use (the hardest on a fuel system) and I can still go out, let it run 5 seconds and the truck fires right away and stays running.

The only thing that's probably going to happen, is the sealing gasket on the pump head will start to leak, which I keep an eye on and it hasn't happened yet.

Mark.

[bmoeller]

The piston style pumps prime MUCH faster than the typical diaphragm pump. Though, mine truck will usually start without having to prime it after a filter change. I just put my thumb over the center (clean side) hole, and fill it from a gallon jug I keep for that job. Fill almost to the top, put oil on gasket, set in and carefully spin it into place. Fires right up.

With my '97, I prefilled a bit, then the primer button worked quick and it fired right up as well.

[cmann250]

I don't see any reason to replace a lift pump with another stock one, unless you have way more will power than most people on this site As soon as you tune it up, even a brand new lift pump can't meet the need. That's why I have a LPPLP on my Dodge and a stock Delphi LP with under 5k miles on it on the shelf

[RCCUMMINS89]

I've never touched the primer bulb or filled the new filter with fuel... she'll idle low for a while but always keeps running.

[Farmboy]

Ok I definatly want a mechanical LP... Now, anyone have any suggestions on where to get one?