Truck in Sig.
Just replaced the VP44 last weekend. Sunday had no issue with starts, Monday morning cranked for about a minute and then started. Restarted fine till it sat for a couple of hours then long cranking to get fired back up. Tuesday started right up every time. Now this morning (Wednesday) long cranking to start again after overnight sitting.

Never did this before the VP44 replacement. What do I look at first.

Thanks

 

loose connection on the return lines, or the suck side of the LP, if there are air leaks there it will allow the fuel to syphon back to the tank, a faulty fuel cap will do this as well, did the new VP come with a new pressure relief valve? what fuel pressure do you have?

 

From the lift pump 14. Would a loose line leak fuel?

yes it came with the new relief valve but I did not do the install. I assume he put in on..... and did not reuse the old one.

 

We're having a simular problem on our '99 3500. Where is the relief valve located? We pulled the return banjo line off and didn't see anything in the VP.

EDIT: Found it. I have one of our guy's headed down to Pacific Cummins as I type this for a new relief valve/banjo fitting. We'll see if this cures this irritating issue.

 

check to be sure the relief valve isnt stuck open causing the pressure to bleed off and fuel syphon back to the tank. make sure there isnt any leaks anywhere.

also bump the starter a time or two to get the fuel pressure back to the vp44 before cranking. all that cranking with no FP is never good for it.

 

let us know if it works, i hear a lot of hard start complaints

 

i am having the same problem with my truck. I have the walbro setup on it. Where exactly is the relief valve located. This problem just started Sun. I show 21psi idle and 15-16WOT. dunno where to start. gonna look over all the lines and pump tomorrow and see if there are any leaks.

 

It's in the return line banjo fitting itself; at the IP.

 

thanks for the info