Archived lift pump!?

[PhillipFleming]

Ok guys my 95 cummins has been runnen just fine upuntil today. i went to leave after it had sat for apx 4 hrs & outta nowhere it took 3 tries to keep er runnen. (mix of white & black smoke) then just normal pre boost black. went 6 blocks & she fell on her face! wouldent start! figured out that after hitten the primer button a S!&* load of times i couldnt hear the o/f valve bypassing fuel. after getting towed home ive found i have no fuel pressure & a S!@% load of bubbles when tryen to bleed the system. Bad lift pump?!? i got rid of the pre heater this weekend & just re installed the pre filter with no issues. im open for any ideas. also noted i took a while for the system to prime after heater was deleted but once it did prime had good pressure apx 30psi its also had the 'ticking" now & again from the lift pump. just given as much info as possable. Thanks!

 

[BigPapa]

Are you SURE you have fuel in the tank? Put some in there first. It's easy, it's cheap, and you have nothing to lose.

Mine ticks when I need to change the filter.

 

[PhillipFleming]

the gauge is reading over 1/4 tank & i have run it until the low fuel lite is on before with no issues. i can rock the truck & hear fuel sloshing in tank. ive got bleeder screw loose & when trying to prime itll just start pushing bubbles out around it.

 

[Missouri Mule]

Normal for air bubbles to come out. How many times are you pushing primer?

Squeaking noise from overflow valve mite be normal or not normal

 

[PhillipFleming]

i can push it until my arm hurts. just bubbles. ive always listened for the sqeek of the of the o/f valve the it pops rite off after a filter change. it wont build any fuel psi just foam. will a lift pump fail like this? or is a air leak in devloped in the course of a day more likely?

 

[Missouri Mule]

Try five gallons of diesel in the tank! Just to rule it out.



The Infamous Fuel Sending Unit can start sending bad readings to the gauge at anytime.



If that fails do a fuel pressure test. 20 psi or more at idle, at 2000 rpm should be 30 or a little higher. If it isn't at the correct readings squeeze the rubber return fuel line with pliers if pressure goes up it is the overflow valve if goes up slowly or doesn't go up lift pump.



Usually I have to tighten the bano bolt back up to get the overflow valve to squeak but the last time I did it the overflow valve(new) did not sqeak. But it was the first time I started the Mule without blowing white smoke for 30 seconds to a minute after I changed the fuel filter.



There is also a chance their is an air leak in the pick-up tube.

 

[HHhuntitall]

... . or it's leaking air somewhere by the prefilter. That's all suction, so if it's leaking any air, it's gonna lose prime.

 

[PhillipFleming]

fist off thank you guy for the help. & huntitall you were rite on the money! it was an air leak from the supply line that runs up the transmission to the pre filter. i had seen a few hair line cracks in it & thought why not replace it. & presto! it primed & ran! & it ran great ta boot! it hasnt run that good in a long time!! its never really given me the hard start that air leaks do so i never give it another thought. again thanks all. man thease things are air sensitive (spelled that wrong).

 

[HHhuntitall]

Alright!! Glad I was right about something this week!!! If you look for the Gates Barricade fuel line, used for fuel injection, it won't crack like regular fuel line. Or something biofuel compatible. I fix this crap all the time, and I hate it when I have to redo something I've already done..... The rubber fuel line you get today isn't worth buying. You'll be redoing it in a few years if you go cheap.

 

[seafish]

If you look for the Gates Barricade fuel line, used for fuel injection, it won't crack like regular fuel line. .

HH, do you know if this stuff will work with push lock fittings??