I replaced my lift pump and overflow valve a month ago and suddenly it act like the lift pump is dead. I was wondering about throwing a electric pump on frame. Anyone been there?

 

I wouldn't, but that's me. Do you have a pressure gauge to verify?

 

I used an electric pump to prime mine...
It seemed to push through the mech lift pump fine.

 

When you start running big hp, you usually need to go to a electric lift pump since the stocker won't keep up. Nothing wrong with a FASS/Airdog on a 12v.

 

Does the cam that runs the lift pump ever round out therfore moving the pump arm less?
I can primer button up to 20ish psi but as soon as I start the truck she slowly goes to 0 psi and then the truck starts to run crappy and white smoke comes from under the truck like you are at a KISS show. I have a new LP coming under warranty from Geno's that is going in on Weds.

 

Many peope run a holley blue or black WITH the lift pump.

If you want to eliminate the lift pump, you need to do an AirDog or FASS.

I did an AIrDog almost 2 years ago and wouldnt have it any other way.

 

Unless you're running or planning on running in excess of 500hp keep the mechanical set up.
Very economical and reliable.

 

i dont think i have 500 hp and everyone told me to keep it mechanical, even though the parts were new i had a lot of problems so i finally broke down and went with a new air dog 2 which eliminates the filter, prescreen and heater. It runs so much better and keeps 45 psi of fuel pressure under 70 psi of boost....go electric if you got the coin.

 

mechanical lift pumps are very reliable.... I'd check to see if something is releasing pressure before replacing.

replaced LP at 120k miles on my old 97 12v... mistake... the old one was fine. the problem was the pressure relief valve leaking down. by the way replacing mechanical lift pump is a major PITA!

putting a gauge on is the best way to diagnose. find instructions in the sticky section.

first thing to do is take a long handled tool... like a extra large screwdriver. then use tool on lift pump button to manually pump up to pressure. when you hear the pressure relief valve release. then it's at highest pressure valve will allow.

after pumping up.. quickly start your motor before pressure leaks back down. if this procedure works ... then probably bad relief valve

 

Ditto on the mechanical. They will push enough fuel for 99% of owners.