Archived Bad Lift Pump?

[T Smith]

Another fuel problem... '00 CTD



I changed the fuel filter, and completely drained the canister. Numerous times I did the bump the key and let the lift pump run while holding the Schrader valves open to let air out.



After about 10 times, and still no fuel coming out, I decided to take the cover off, and found about a half inch of fuel in the bottom.



Ran the lift pump with the cover off, and no fuel. Unplugged the feed fuel line at the lift pump, no fuel, and cannot feel any suction from the lift pump.



Truck has half full fuel tank, the fuel filter cannister was full when the filter was removed.



Do you think it's a bad lift pump?



Thanks for the help!!



TSmith

 

[Whitmore]

Sounds like a bad one to me too, I would get a meter and check to make sure you are getting power to the pump before I replaced it... ... ... ... ... ... ... ... ... ... ... ... Kevin

 

[T Smith]

Poblem Fixed!

I talked with Cummins and Dodge techs about the problem and they both said that when I completely drained the filter canister, that it most likely lost prime in the pump. Both (I'm not just a little paranoid about that lift pump!) said that the lift pump should not have been damaged.



The fact that everything was working fine before the filter change led them to believe that the pump had just lost prime, and should not have been damaged at all by the 'dry' running of the pump. I guess we'll see...



To fix the problem:



- I filled the canister with clean fuel to help prime the pump.



- I ran the pump two cycles while holding the Schrader valves open. I immediately could see fuel coming out.



- Truck started after about 15-20 seconds of cranking.



TSmith

 

[Ron Bissett]

Re: Poblem Fixed!

Originally posted by T Smith

I talked with Cummins and Dodge techs about the problem and they both said that when I completely drained the filter canister, that it most likely lost prime in the pump. Both (I'm not just a little paranoid about that lift pump!) said that the lift pump should not have been damaged.



The fact that everything was working fine before the filter change led them to believe that the pump had just lost prime, and should not have been damaged at all by the 'dry' running of the pump. I guess we'll see...



To fix the problem:



- I filled the canister with clean fuel to help prime the pump.



- I ran the pump two cycles while holding the Schrader valves open. I immediately could see fuel coming out.



- Truck started after about 15-20 seconds of cranking.



TSmith

Now you will not know if its good or bad . Get a fuel pressure guage and know what is going on all the time don't leave home without one . Your choise . Ron in LOUISVILLE KYOo. Oo. Oo.

 

[Bigsaint]

Lost prime to the lift pump

The last time I changed my pump, I also had 1/2 a tank of fuel. Normally I take a good soaking in diesel when changing the pump ( mine is aftermarket and located on the frame next to the tank). When I disconnected the compression fitting I use to connect the braided line to the OEM hardline, coming from the tank, it dribbled out and then stopped. There was no continous flow. Now doubt that, coupled with the fact that your pump is probably mounted in it's original location, would cause difficulties for the Carter pump to pull the fuel all that distance. Yet another good reason to move the pump back by the tank. If you lose siphon flow with the pump by the tank, it only has to draw the fuel a few feet, rather than the length of the truck from the tank to the block.



I would still do a pressure check on that pump, bet it's not at the psi's it should be. IMHO it should have had the resolve to pull the fuel from the tank, even with a loss if siphon flow.

Scott W.

 

[abledog]

This is just a WAG but could the tank be under a vacume?



If fuel in tank is hot at shutdown it may be possible to pull vacume as it cools.



Terry