Fuel pressure problem

[mopar1968]

:? Ok to start this, fuel pressure is running at 15 psi on pressure gauge, would not adjust down, replaced regulator with holley regulator, ran couple times, guess what 15 psi again, ordered a billet regulator from Ron Owens installed guess what ? you guessed it 15 psi again, i have adjustment screw all the way down flush with top of regulator to get 7 1/2 pounds. Any answer's to what may be going on? plugged filter? bad pump?

[zipper06]

Gage, not right, if the carbs are not leaking by i doubt if you really have have 15psi to the carb. I'm not a carb person, totally injection, so i could be way off o this one.

JMO

Zip.

[hammertime]

1st thing I'd do is replace the gauge.

[Scooterz]

Mopar: I have replaced 3 Holley reg's in 6 months... one of which had a good diaphram, but was allowing fuel by it from faulty machining... causing fluctuating fuel pressure. I have one guage on the dual feed, & another liquid filled unit separately now so I can check them against each other to make sure the pressure is right.

[mopar1968]

:? I have allready replaced the gauge with a liquid filled one, three regulator's later still high pressure, no fuel flowing in carb, needles holding properly. :?: :?: By the way the gauge is mounted to one side of regulator and line to carb on other side of regulator :!: :!:

[hammertime]

Which fuel pump do you have ?

[mopar1968]

holley blue pump.

[Scooterz]

You don't have a return right? Man.... that does not make sence... I can see why you are stumped right now. I wonder if a air is entering into the fuel system somehow...

[mopar1968]

Right no return. I would love to go to fuel injection but know nothing about it.

[Scooterz]

Amen to that... same here. The Holley blue... is it maxed at 15psi/output?? or can it produce more?

[mopar1968]

Well i don't know, all i know is when i look at the gauge it is against the needle stop @ 15 psi, i am sure it will pump more due to having to run a regulator with it. Just checked summit website 15 psi is max pressure. Just thought i would let you know this on my cuda not my dart.

[Scooterz]

WTH?? as I have said before, I am no expert, but this is pretty abc... that is frustrating!! So you are maxed out psi, 2 guages, no overflow/flooding, reg is good, but adjustments make no difference. No return. depending if there were any blockage, I would think that would lower the psi... thinking out loud here.... I wonder if air is getting in.... causing this somehow. Pump sucking air & forcing it in the fuel lines???

[mopar1968]

I f this helps this started when i made a intake and carb swap, this is when we noticed fuel pressure, let me ask a dumb question, If the filter before the pump is dirty seem's like the pump might pump harder to get fuel to engine? less flow to pump from cell?

[Scooterz]

Heres the thing... in terms of knowing what you are doing, you are probably more expirenced than I. But this is something simple I think... I don't know that your filter being dirty is the cause (depending on style) but I wonder if it is like the "AN" style like on mine witch could cause more pressure if backwards... it would be easy to do, & not so easy to notice. (They look the same ft to back)

[mopar1968]

Never had filter off or any lines loose since building car, only lines @ regulator for intake swap. then bam this happens? Filter is a russel 8an style in line filter.

[Scooterz]

This is hurting my brain... the psi should not be relavent to an intake/carb swap.... WTH?? I am going to ask my race-eng mentor tommorrow & see what he says. when you fix this, please let us know what you find too... this would frustrate the hell out of me if it were my ride.

[mopar1968]

I am a auto tech by trade for 27 years and it has me baffeled, tried everything, before coming here and looking stupid.

[hammertime]

I am a auto tech by trade for 27 years and it has me baffeled, tried everything, before coming here and looking stupid.

I am baffeled also here, been thinking and I am going to say we are missing something esay on it.

Does the gauge read the same no matter if the engine compartment is warm or not ? I've had gauges go screwy on me when the motor gets warm.

[mopar1968]

no doesn't matter hot or cold

[fishman1]

If the filter is before the pump and the filter was plugged the pump would caviate and you would loose pressure and flow

take your gauge and run it into the fuel rails that go into the front and back of the carb and see what happens.

also if u have liquid filled gauge drain the fluid out of the gauge as the fluid is glcerin if i know how to spell and fuel gauges are recommend dry to read probably

if you really had 15 psi at the carb your seats and needles wouldn't seat and you would flood the carb as they are designed for 9 psi

Like i said the gauge and mounting location has to be the problem, or i could be wrong but i would try it

[mopar1968]

The gauge location has been the same since the car was built.

[Scooterz]

Mopar: any luck yet? I have not been on Rj for almost a week....

[mopar1968]

Well maybe i talked with Ron Owens on the phone and the only thing he could come up with is maybe either the pressure spring in the pump is broken or the pressure valve is stuck in the pump, causing it to pump full pressure and over come the regulator, he is sending me a pump to try and see if it cures this problem. I want to thank all you guy's for your input and help! thanks again. Mark

[mopar1968]

:D :D Just to let everyone know Ron Owens hit the nail on the head, installed fuel pump he sent and fuel pressure problem solved, Thank everyone for your help. Mark

[dparker]

Not to say your gauges aren't accurate but I've never seen any needle seats that could withstain 15lb of pressure with out bleeding over. Maybe your reading gauge pressure before regulator, or one or both gauges are reading inaccuratly.

[fla1976]

Sounds like you need a bumper sticker "RESCUED BY RON". It's nice to have a parts supplier that is also a thinker.

[mopar1968]

:D :D You got that right, if i had a sticker you bet it would be on my car, has helped me more than once. :!: :!:

[dparker]

Hey Mopar what was the problem with the 15psi? Did you get it fixed?

[mopar1968]

Yes got it fixed thanks to Ron Owens, the pump was stuck wide open, relief valve wasn't working. got a pump from Ron everything back to normal.