I need to replace the lift pump on my 93 W250. I picked up the pump a few days ago from NAPA. It says made in South Korea on the box, which probably isn't good? Anyway; I misplaced my FSM a while back, and was hoping someone would know the torque specs for the lifter pump bolts? Also; what type of gasket sealer is best to use on the included paper lift pump gasket?

 

I just looked at the FSM and it didn't give a torque spec. that i could find anyways. I just snugged them up good. I used some red high temp gasket maker from work, it seems to have worked alright.

 

Much obliged Hounddog, thanks!

 

I have always used Permatex 2 Form-a-Gasket Sealant NON-HARDENING for any such similar applications.

I ?think? this is the same stuff as the old tried and true Mr. Gasket stuff.


I smear a thin coating of this stuff on BOTH sides of the gasket and any subsequent future removal of the part results in a clean release of the gasket, allowing it to be reused AND no scraping needed.


As for the mounting bolts, just past snug is enough.

Too much and they will snap.

I have on hand a bunch of 8mm x 1.25 ?I think? studs that I intend to use to replace all the lift-pump and water-pump bolts in all of our engines, thus making it a lot easier to line things up.

I suggest you procur a set of studs/washers/nuts when you buy the new pump.

 

Now those are some good ideas. And I really like the studs for the lift pump and such...make life a lot easier.

 

BearKiller,
Thanks for those great tips! If the weather cooperates tomorrow, I hope to get the new pump installed.

 

If this is an un-molested factory-original style set-up, I suggest you also pick up a few feet of new diesel-rated fuel-hose, ?? 30RC I think ??, (those numbers may not have anything to do with fuel-hose; they just jumped into my head).

I am unsure if factory issue hose is 5/16 or 3/8; best to just get some of each, plus new clamps.

This new hose is to replace that short section between the frame-rail and lift-pump.


While you are at it, there is also a short section at the fuel-tank pick-up unit.


These are notorious to get all dry-rotted and crackledey and develop an air-intrusion leak, if not just break plumb off and shut you down somewhere inconvenient.

 

Bear,
Yes; this is a stock OEM setup. I have to see if I have the time to get the line back to the tank replaced. I need to get the old girl back on the road in about a week, in order to move some tables etc. out of a storage unit Would you or anyone else have a Dodge/Cummins part # for the OEM upper hard fuel line with the 17mm banjo bolt fitting, as well has the lower hard 90 degree fitting - which snaps into the fuel line. I guess I will need a Lyle style fuel line tool, in order to disconnect the lower line on the lift pump? Also; where's the best place to get fuel line - JEGS/Summit??

 

Since every last one that I have ever worked on has only ever had a plain old 1/4-NPT X hose-barb 90* EL and a plain old hose-clamp at that lower fitting, I just assumed they all did.

For just plain old black rubber fuel-hose, I just buy it by the roll (or by the foot) at NAPA on account of their hose being GATES brand.


A much better option than the factory hard-line is to forget the banjo fittings.

The top lift-pump fitting should be 14MM x 1.5 --- use a -06 JIC metric adapter there.

All the rest of the fittings, both sides of the filter and the injection-pump inlet should be 12MM x 1.5 --- use a -06 metric adapter at the filter head.

Use a -06 JIC x straight hose-swivel at the lift-pump.

Use a -06 x 90* hose-swivel at the filter.

Complete with a length of 3/8 rubber hose to fit.

The JIC fittings and flexible hose are much easier to work with and will not develop vibration cracks like rigid hard-line will.

 

Bear,
Thanks for the info on the JIC fittings! I will pick those up and get some fuel line from NAPA. Yeah; the lower 90 degree fitting on my 93 W250 lift pump has a fuel clip type connection, no hose clamp. If I had a digital camera I would take a pic of the clip, but my FUJI pic camera died awhile back. Thanks again for the help!

 

BearKiller or anyone else,
I just got around to replacing the oem fuel line, with 3/8" Gates fuel hose. I am going to replace the oem fuel line from the fuel filter to the fuel pump next, with 3/8" fuel hose as well. When I have the time, I will probably drop the tank and replace the suction line as well - Per BC in the sticky.
I am pretty sure there is no need to replace the oem return line? Would there be any benefit to changing this out to 3/8" fuel line as well? My plastic return line is still in fairly good shape. I don't think BC did, when he upgraded his fuel line and suction line to 3/8." I may be wrong though?

 

The return-line has no pressure on it to speak of, UNLESS one is running a bypass regulator, in which case a larger diameter return-line would be called for.

I would leave the plastic line alone, but I would go ahead and replace the sections of rubber line, 1/4" I think.

 

If you are staying stock the factory return should be fine but, if you upgrade to a 2nd gen pump or an electric one and use a bypass regulator you might want to consider it. Of course if you already replaced thee supply side you could use the factory supply line as an extra return. IIRC BC did this...

 

Thanks for the reply Bear and Marc! I am not running the 2nd gen pump, nor a by-pass pump (such as Air Dog etc.), so I am going to leave the factory plastic return line.

 

Bear; Marc etc.,
I finally finished plumbing my 3/8" fuel lines - from the tank to the lift pump, then from lift pump to fuel filter, and on to the fuel pump.
Now; I need to tighten the JIC6 straight barb fitting on the front of the fuel pump. I am having a hard time getting an open end wrench in there. Not a lot of room between the bottom of the pump and the timing cover! Do I need to loosen the fuel pump and rotate it, in order to get a wrench in there? Or; use either a crows foot with a socket extension and ratchet wrench. Or; use a stubby wrench? Any help is appreciated!