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loosing fuel rpessure ?

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loosing fuel pressure ?

So I finally get to drive my coronet, make it 2 miles from my house and it dies. Starts, stumbles and dies. was able to keep it running with external fuel source. When I bought the car I had a feeling the tank was shot, well now it was time to address it. Inside of tank was disgusting, loose crap covered the bottom. I replaced the fuel tank, sending unit, main fuel line. New fuel pump, filter and rebuilt the carb. Added an earls bronze filter and pressure gauge. replaced rubber hose from pump to carb. Start the car, 6psi .... after running for a few minutes can watch the gauge slowly trickle down to zero but the car stays running. I'm stumped. fuel pump pushrod is good, I checked and measured before I put the pump in. Could it be an issue with the advance auto fuel pump ? Maybe heat related ?
 
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What grade of fuel are you running?
Do you have a phenolic plate between the carb and intake?
What kind of carb is it/does it have bowl sight glasses?
 
What grade of fuel are you running?
Do you have a phenolic plate between the carb and intake?
What kind of carb is it/does it have bowl sight glasses?

I run 93 octane, no carb spacer. Holley 650 on aluminum intake. No bowl sight plugs, but I have adjusted the bowl level with no issues.
 
How long does it stay running? There is enough fuel in the bowls to let it idle for a minute or so, maybe longer. If you crack the throttle (rev it up a couple of times) what does the fuel pressure do?
 
Get back under the fuel tank and look at the rubber fuel hose that connects the fuel sending unit to the fuel hard line, is it kinked?
 
Fuel filter is between pump and carb. The car will stay running until I shut it off. I drove it yesterday like this ! Fuel pressure doesn't move at all when rev it up. Just went out and messed with it again, no rubber hose collapsing. I did notice if I give the hose going into the gauge a quick squeeze the needle will jump up then back down. Solid 6psi on start up, eventually will creep down to zero, even just idling in the garage.

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Get back under the fuel tank and look at the rubber fuel hose that connects the fuel sending unit to the fuel hard line, is it kinked?

Nope, all that has been replaced. New hoses, clamps, etc .... Straight shot from sending unit to Main line.
 
Try a different gauge.

X2. If the cars drives regardless what the gauge says, get a new gauge. I was racing my new build a couple years ago and had weird fuel pressure problems but the car ran fine. When I was discussing the problems, a veteran racer friend of mine immediately ask me "Is your gauge liquid filled?" It was. I replaced it with a non-liquid filled gauge and no issues since.
 
My problem was created by myself. Found out the hard way that liquid filled gauges don't do well under the hood. Drained the fluid and vented the rubber plug, reading is steady at 6psi. Stupid gauge ! Thanks guys, no problem goes unsolved !
 
Glad you found the problem. By the way, mine was mounted outside on the cowl.
 
Would not have thought that..

Yeah tell me about it. It was killing me and I was going nuts trying to figure out why I had no fuel pressure ! A quick google search helps from time to time. Needless to say I will not be buying any liquid filled gauges anymore ! Apparently Auto-meter does not make anymore liquid filled fuel pressure gauges for this exact reason. You'd think companies would have a way to vent the internal pressure out of the gauge and keep the liquid in.
 
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