mhammer73

I have been fighting a high fuel pressure problem for a while now. It started last winter and has been the same since. For a little background I'm running a frame mounted carter 7 psi pusher pump along with the stock pump. When this was done I was running a electric gauge and it ran about 20 to 22 psi at idle. It was that way for probably a year. Then I went to a edge juice with attitude for my fuel gauge. Everything was fine for about two months then the idle pressure started to climb. It is measured at the inlet banjo on the injector pump.

I changed the sending unit on the gauge and then checked it with a mechanical gauge when this was going on. It now idles at 30 to 32 psi. I replace an IP this fall and the return check valve on the pump. I still am running the 30 to 32 psi.

I checked my pumps and I'm pretty sure this is being caused by a restriction on the return. It will idle at 18 to 20 for just a little bit at start up and then go to 30 to 32 psi.

Has anybody had this problem? How is the return set up where it goes into the tank? Is there a screen or filter I dont know about?

Any help would be much appreciated!!

Thanks,
Matt

dozer12216

Take the return line loose at rear of engine and add a hose to a catch can for testing. If pressure is now normal, you might assume a restriction exist. I'm not sure running pumps in tandem is recomended. It may very well be that a pump at earlier time was not working correctlly and cleared itself eventually, causing overpressure. JMHO

mini14

the only restriction that i know of is the overflow valve on the pum, should start to bleed off @ 15 lbs, pull it and check to c if it is...i have the 4601hp on the frame and the stock lp and all i c is 15-17lbs, did u put a filter or screen before the pump inlet to the pusher ? it is recommended, if u did change that out, if u didnt do it. when running pumps in tamdem u add the psi value together to get acutal psi. nothing wrong with adding a pusher.7 psi+ 15psi(factory pump)=21psi thats the most u should c.

Gear Poet

Might be a check ball issue in the stock lift pump. Normally if the check ball assembly fails, pressure bounces around. However, on my second stock pump failure, I saw pressure rise like that and remain constant.

Zeus1987

i have noticed that when i take my harness off my f/p sender for my juice/attitude that the display will read 32-33 psi. check to make sure there is not any water or corrosion.

high bid

I'm running fac LP and a holley blue in tandem. Replaced all filters pre-holley and factory...still psi was about 30. Anything over 25 psi and your factory filter canister will begin to leak around the top where the rubber sensor is. I installed the regulator that came w/the holley and have it as low as it will go which now gives me 20 at idle and 15WOT. I think mini14 is correct about adding the pumps psi output.