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Fuel pressure not above 30 psi...

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zaydevhimself

Probationary Member
4
0
Jan 16, 2013
north wales, Pennsylvania
Hey guys. I havent ever posted here before but have always used the existing forums. I have kind of a very weird issue. The set up i have going n is a full blow twin intank pump set up. both Walbro 255HP pumps both rewired off the battery getting 13.6v each. 8AN feed line 6AN return line. Fuel lab 818 fuel filter 8an fittings obv. stock fuel rail 8an in 6an out. 1120cc FIC ball injectors. Aeromotive regulator in from the side. The first thing i thought was going on was the regulator was leaking so i replaced that with full brandy new. Nothing changed. Then i had changed both walbro fuel pumps and still nothing. checked the ohms on the ones that i took out and they are .8 so they were good all along. Im running out of ideas as to what is wrong. Before you ask the regulator is screwed all the way down and it still wont go above 30psi.
 
try pinching the return line to see if the pressure comes up that will tell you that there is something wrong with your regulator . if the pressure doesn't rise then it's somewhere else.
 
yeah i also replaced the gauge with one by the same company. The Screw doesn't adjust it at all. i mean i suppose it would if i unscrewed it all the way. As of thus moment i have a new filter screen 40 micron ss for my 818 fuel lab comming in tuesday so im going to try that along with a new fuel rail (i know that shouldnt be the problem but i figured i wanted one anyway for the hell of it so i ordered it from extreme to avoid paying an additional handling fee)
 
What about the dual pump setup itself? Possible one or both pumps are pushing back through one another? I always figured a dual pump setup would have a one way diaphram/valve on each pumps line before they "Y" together. Just a guess :idontknow:
 
Well i just replaced the fuel rail... And the fuel lab filter screen and im still at the same issue. I have checked the lines multiple times for kinks. I have hoses ran from the pumps to hardlines i ran under the car then hoses again etc. Does anyone have any other suggestions? I dont understand a fuel system is so basic but im at a complete loss...
 
Like i said get a pare of needle nose pliers and pinch the return line after the regulator . if the pressure rises then there is a problem with your regulator if it doesn't then your not getting enough fuel from your pumps or there is a restriction somewhere . it's all about process of elimination .
 
Like i said get a pare of needle nose pliers and pinch the return line after the regulator . if the pressure rises then there is a problem with your regulator if it doesn't then your not getting enough fuel from your pumps or there is a restriction somewhere . it's all about process of elimination .
I agree with Lou98GSX. Even though you have changed the regulator, lets start eliminating possible issues. Under a load does the pressure decrease or stay the same? Could the pumps be losing the power its needing under a load!? Just an idea!
 
I have found the issue. It was the internal fittings on the full blown housing itself on the inside of the tank. was leaving the pumps and leaking right past them. weird. tightened up the threads and the clamps presto chango everything works the way it should. Pauleyman FTW LOL
 
Awesome glad you found the issue! Always best to go by process of elimination!
 
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