so i've replaced the lift pump and overflow valve in the last week.

just did the overflow 15 minutes ago.

reads 10psi at idle and drops right to 0psi under any load.


i have my gauge hooked up right at the banjo bolt going into the pump. drilled and tapped banjo and then have an 1/8" compression fitting into 1/8" hard plastic line to the gauge in the cab. is this wrong?


whats going on....

 

What was your fuel pressure after you replaced the lift pump, and before you replaced the overflow valve?

 

was high... like 40ish but thats because i put a bic pen spring in the overflow to get by.


wondering if my gauge is toast, i didnt have a needle valve for the first few days i had the gauge in...


got a valve and it didnt seem to do anything like it still shuddered. so i'm leaning towards gauge being toast.

its starts easier and runs smoother than it did before doing overflow.

 

get a new guage the pulsations will kill it fast...

 

Sounds to me

like one of two things, i have gotten a bad OFV before, without a spring in it, which caused my low FP, second of all, runnin the gauge without a NV, i think is what killed ur gauge, or its innaccurate, Have u performed the spring mod on this second OFV? That might be worth a try, since the OFV can come bad as well. Sounds like u have the gauge correctly plugged in, I cant think of anything else, if u say the truck runs and starts better with the new OFV, id suggest a gauge, but do perform the spring mod to see what it does, just out of curiousity..

Rick