Just stumbled across this site while surfing for information on cummins lift pumps. I've been glued to this site for two days. I have learned more about my truck in these two days than in the last year I have owned it.

On my 1994, I have a small heating element which mounts to the top of the lift pump/strainer assembly that is burnt up along with a very short segment of the wiring that operates it. If I understand correctly from my local dealer, I have to replace the ENTIRE assembly (over $300) to get the heating element and wiring I need. Truck has 173K, starts great and runs great once its warm. Do I need to be concerned with getting this element replaced? Is there performance that I am sacraficing or damage I might do operating without this heating element. Should I plan on replacing the lift pump while involved with this project since the lift pump has 170K+ miles on it?

Any help appreciated.

 

I wouldn't replace the lift pump unless it's bad. The device you speak of is separate from the lift pump and is the fuel heater. You may or may not need it in Kansas, I certainly would want it if I drove in temps below zero very much. The parts are available separately from Cummins, heater element 3907766-s $35.18 or cable harness 3843722-s $49.39

 

Thanks for the information, we only have a limited number of below zero days so it sounds like I can possibly get along without replacing the fuel heater.

I have never had any starting problems with this truck, it sounds like a new one at idle. I can prime it several strokes after changing the fuel filter and it typically fires right up, it may idle rough for a little while but smooths out whinin minute or so.

Ever since I have owned this truck though, (my first diesel which I have absolutely fallen in love with) it has not ran smooth, even during warm and even hot summer weather when you try to start it up and drive off. It wants to smoke and sputter for a while, if you try to push on the accelerator it acts like the bottom drops out especially when its cold, and then within a few minute it's like it gets the fuel it needs and it will take off and run like a scalded dog until you shut it off and let it cool down again.

Where do I start looking on this? I have been researching this site, which is absolutely awesome, and have a few ideas but I know there is a library of information available here that can sure help. I have never removed and checked the fuel strainer on the bottom of the lift pump assembly for potential blockage, what about the overflow valve I have been reading about, or could it be a fuel leak somewhere in a fuel line?

Any idea on the plan of attack would be appreciated, thanks!

 

I would start by replacing the overflow valve, might be all it needs.

 

Thanks for your advice. Do you think a parts store like NAPA will have the overflow valve I need? What should I expect to pay?

 

Precision Diesel Injection and Turbo Inc.
Marty Tompkins
888-734-7349
$35 + $7 shipping and handling.


As Infidel would tell ya, Marty is a good guy to do business with and you won't find a better price, including the shipping.
Dave

 

If you're not going to replace the fuel pre-heater element and wiring harness, don't unplug the harness from the element. The pins inside are known to leak and you'll end up getting air in your fuel lines. It happened to me.

 

berner,
Your post is interesting because of the fact that the heating element along with the mounting bracket and a short section of wiring were completely toasted. I removed the two allen head screws that mount it to the top of the assembly, removed what was left of the burnt element and never replaced it. Do you think that is causing some of my performance problems?

I have noticed over the last couple months some exhaust smell in the cab that is getting worse, do you think might also be looking at a plugged up cat? The exhause looks solid but I'm quite sure it is factory.

Thanks for the information.