Engine/Transmission (1998.5 - 2002) D/C's Lift Pump Test

[PKleine]

I've been lurking in the background for a while now; plenty of great information gets posted here. But now it's time to make my first post.



I recently installed gauges and of course find my lift pump is marginal. Idling I see about 10 psi, running down the road at 70 mph/2000 rpm it show about 6-7 psi. WOT @ 2500 rpm gives about 2-4 psi. No codes are set. The question is: will D/C consider this pump defective? Does anyone know what test the dealer will perform to verify the pump is defective? -Thanks



Peter

 

[Thomas]

Diesel Transfer Pump Diagnosis



It's difficult to say what any particular dealer will do.

 

[PKleine]

TSB Link

Thomas, Thanks for the link to the TSB I suppose I should run that test before I take it to D/C, might save myself a few bucks if the pump tests good...

 

[DMC]

Mr. Kliene:



Have you checked the fuel line connections for tightness, and fuel filter. And also the prefilter, and overflow valve.

I am only making a suggestion.



Good luck



Don

 

[mpray]

Had much the same problem myself. Idle of 11, cruising at 70 about 7, wot could get down to 2. Went to dealer this last Thurs. they told me first that DC doesn't want to see press. below 5 at any time. After taking my truck in the shop to conduct their tests they brought it back out and said it was good to go. I talked with the shop manager about the pressure specs. He said that DC no longer deals with pressure from the lift pump that it is by volumn of fuel pumped. 48 ounces per 20 seconds min. 52 oz. max. Said my truck pumped 50 the first time and 51 oz the next time. This must all be done at idle as I never heard my truck rev up or leave the building. I was keeping a close eye on where it was and who was in it. Hope their right and I'm not left on the side of the road. They did tell me that the sending unit for my press. guage was shot as they could change press. readout just by snapping it with their finger.

 

[CFAR]

You might want to consider changing it yourself if they deny it. That way you get a new pump and have a spare.

 

[dresslered]

CFAR has some good advice. Your present pump sounds marginal, and unless you have a great dealer, just throw it under the rear seat for a spare. I think that you will notice quite a difference in pressure readings with a new pump.

 

[BarryG]

Mpray:

I believe they do this test without even starting the truck. They just turn the key on or bump the starter to get the lift pump to run so there is no load just free flow.

 

[Brand-X]

98. 5-2002 diesel transfer pump diagnosis

 

[kscheffler]

Just Buy the Damn Thing

I tihink I am going to just buy one. What is the current part number for the lift pump? I do not trust the local dealer they don't know squat about Diesels. . Thanks for the help... kts

 

[PKleine]

Cummins Part Mumber

KTS,



I've almost decided to buy the pump myself that way I'll have a spare. This link will take you to a thread with the part number in it. I haven't verified part number or checked the price. Good luck...



PK

 

[CFAR]

Don't know where you are in Northern CA.

Remember Cummins will be cheaper that the local Dealer.

Here is a link to the cummins service/parts locator.

http://www.cummins.com/service_locator/index2.cfm