LB7: Fuel Prob.

[sarman59]

Hey yall, Im new to this sight and having a problem with my truck. It will not stay primed . It shut off on me one day, I can prime back up and will start but i noticed that the plunger on the priming pump is slowly being sucked down and shoortly after the truck will die. Have already rebuilt the filter head but to no result. Please help
. Thanks

 

[BlkMax]

Hey yall, Im new to this sight and having a problem with my truck. It will not stay primed . It shut off on me one day, I can prime back up and will start but i noticed that the plunger on the priming pump is slowly being sucked down and shoortly after the truck will die. Have already rebuilt the filter head but to no result. Please help
. Thanks

Welcome to the site!
:welcome7:
It will help greatly if you fill out your signature and tell us what kind of truck/engine you have.

Are there any strange sucking noises, fuel on the ground after it is parked, etc? Did you replace the fuel filter and get everything snugged up correctly?

 

[sarman59]

2002 2500 HD LB7
No it just cut out on me one day. Changed filter aand rebuilt head unit. No fuel on ground and dont hear any sucking noise.

 

[Burn Down]

Try leaving your fuel cap loose, it might not be venting properly. If not that, take some 1/2" fuel line and stick it in a jug of fuel and hook the other end to the supply on the filter head. You may have gotten something in the tank plugging the pickup tube.

 

[JoshH]

I'm going to move this to the fluids and maintenance forum, so maybe you'll get a little more help. It sounds like you definitely have a restriction in the system somewhere causing the fuel system to pull a really strong vacuum. I can't imagine how much of a vacuum it would take to suck the plunger down. Check all the soft sections of fuel line for kinks.