[polaris_paul]

On my 01 when I go to start it after it sits a day the vp44 is lacking fuel. Changed fuel filter and the dodge in tank lift pump works great. If I just bump the starter befor start it's fine. What is causin the prime loss or can I rig something up so the prime pump runs longer than the initial 2 seconds. Thanks

 

[nickg]

try parking nose down hill first, if truck starts right up(after sitting all night) then you have an air leak on the return side, could be crossover tube o-rings or a faulty tank vent or fuel cap, also relief valve on VP next to fuel pressure test port can cause the same symptoms,

parking nose down or leaving the fuel cap loose will confirm that you have fuel being syphoned back to the tank,

when you bump the starter you should see 20sec or so of priming, tring to get it to prime longer is not going to fix your issue, its just masking it

 

[Ram4Sam]

Make sure the fuel filter cap is tight. I forgot to tighten mine properly after changing the filter one time and had the same problem.

Sam

 

[polaris_paul]

Thanks. So if parkin down hill solves the problem then to find out wHich problem it could be. Fuel cap and vent I can just listen to see if air is commin in quickly when I remove the cap. How about the return line o rings and such

 

[nickg]

on the fuel cap the center button can stick, use your key to push the center to see if its stuck, if you test just by opening it you may or may not hear the whoosh, depending on how long the truck had been running/fuel shoshing, and there should be a small amout of vacuum anyway as it helps pull enstrained air from the fuel.
as for the o-rings they are relatively cheap(under 20$) and you can change the fairly easily, they will usually allow air in (because of tank vacuum) but not leak fuel when the truck is running, if they are excessively bad you might see some small fuel seepage, around the head where the fitting screws in

 

[polaris_paul]

where is this crossover pipe o ring or rings?

 

[rmk4ever]

where is this crossover pipe o ring or rings?

It is what your fuel lines connect to on the head, Pull the lines, use a small std. screwdriver to "pry" them away from the head. O-rings on there!
GOOD LUCK

 

[polaris_paul]

thanks, and what could be wrong withe the relief valve on VP?

 

[spike00]

is it low on fuel? when mine gets to about a 1/4 left it struggles to start but i put nice fresh diesel in and she fires right up every time