truck died?

[NMARSH]

a friend has a 94 3/4 ton that died driving thru town

at low speeds. he primed it and it started and ran a few- then died again. hes replaced the fuel hoses & the lift pump

already. could it be the overflow valve? thanks in advance.

 

[Joe G.]

It sounds like it is starving for fuel. It could be the overflow valve if it really went bad. I would suspect a plugged fuel filter or pre-filter.

 

[NMARSH]

thanks for the reply... . he says the filter is new. also it ran rough

after he primed it. what other options does he have?

 

[Joe G.]

Has he checked the pre-filter? It is a screen in the bottom of the lift pump.

 

[NMARSH]

he said he cleaned it when he installed the lift pump.

he also said the lift pump wasnt an exact match and that he had to kink the large rubber tube between the lift pump & the pre-filter during assembly. could the lift pump be the problem? i think hes leaning that way... thanks again joe.

nick

 

[Bigramguy]

Mine did something similar one night and with the help of some TDR members,I tracked it down to a small pinhole in the fuel heater assy. It could also be one of the "o"rings in there too,above the prescreen. Seems as if the little heater element fried and burnt a small hole into it,which sucked air and lost prime. If I primed it by hand I could get it to run for a bit,then it would run for a bit then sputter and quit. What a pain to find it. I was really close to replacing the lift pump,but a few members guided my through it and I found it. It was actually right in the end of the connentor where it plugs in. I filled it with silicone to get it back to the shop to be repaired. Another sign was the wires going to it were slightly melted. Might want to check it and see. I used to have pics of it but I can't find it. I think it was Hemi@Dart that also had some good pics of it,maybe he still has them ??

 

[Joe G.]

Nick,



These lift pumps are pretty hardy. A lot of them get replaced when the problem is really somewhere else. I think I would look closely at the kink in the hose. Maybe replace it with a longer one that does not kink. The lift pump is pretty expensive so I would exhaust all other possiblities before replacing it. Chris mentions another possibility. There could be something wrong from the pump installation to cause an air leak. PITA to find!

 

[NMARSH]

thanks for the help guys.

its amazing how many people have saved time & money from this site... hes going to check the pre-heater and the hose. hopefully he'll throw 35 bucks towards a membership too! i know i learn something new every time i read a post. thanks again

Nick

 

[Extreme1]

It could also be the fuel line in the tank being chaffed through. If it goes away with the addition of a couple gallons of fuel, it is probably that.