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Cranky
06-29-2015, 12:45 PM
I have a brand new car that I finally got fired up this weekend. Brand new fuel cell that was empty of course, I had a used 10" fuel filter log that I replaced the element and o-rings in,(had a metal filter and replaced with paper and made sure the element was facing the proper way), brand new Allstar mechanical Carter style fuel pump, Holley fuel regulator going into fuel log/carb. Filled up carb. bowls and engine fired right up. While at idle, only had 3/4 pounds of fuel pressure. Checked all connections for tightness, removed fuel filter to verify the flow direction was correct. Refired, had 3 pounds but then dropped to 0. Car was still idling but I turned it off as to not cause any damage. Any ideas? Anyone use the Allstar fuel pumps? I have ordered a new fuel filter log assembly but besides that, i'm puzzeled.

Matt49
06-29-2015, 12:54 PM
Did you bleed the fuel line from the tank to the pump?

Cranky
06-29-2015, 01:05 PM
Matt, I actually didnt. I presume you mean spinning the motor over and then cracking the line at the fuel pump? I guess, I assumed when it was idling the first time that I was getting fuel. I know what assuming gets me!!!

TheJet-09
06-29-2015, 01:44 PM
I personally don't run a regulator and might be reading your post wrong, but doesn't the regulator go after the carb and not between the pump and carb? It should regulate the pressure based on what it allows to pass through back to the fuel cell.

Matt49
06-29-2015, 02:10 PM
Jet, it can work either way depending on the regulator. Pressure is pressure so it doesn't matter where the regulator is in some cases.
Cranky,
What I mean by "bleeding the pump" is to make sure that it has a fuel head from the tank. It won't pump air.
Break loose the line running into the pump from the tank/filter (just back it out a couple of turns) and put a bucket under it. Then disconnect your breather from the tank and use a air hose nozzle to blow compressed air in (5 PSI is all it takes or you'll make a mess) until fuel starts to leak out the line at the pump. Tighten it back up and fire it up.

race4dad 31
06-29-2015, 02:15 PM
Cranky, I loosen the fuel line at the fuel pump and use an air hose at the fuel cell and blow air (where the breather line or filter is on cell) till I have fuel leaking out of the connection at the pump and tighten fittings. Seems to work well. I do try to use air from my compressor after running it through a air dryer.

race4dad 31
06-29-2015, 02:18 PM
Sorry I see Matt answered with the same post as I was typing.

Cranky
06-29-2015, 06:32 PM
Great guys, I will try the air hose trick to see if there's air trapped in my lines and give her another shot. I will probably wait until tomorrow evening when the new fuel filter log comes in. I will mount it and let you guys know what the outcome is. Thanks.

Brian Gray
06-29-2015, 08:17 PM
Definitely sounds like air. If it's only idling your not going to hurt it . I'd bet if you let it run just another minute it will bleed out the air and stabilize the pressure.

But putting air in the fuel cell will bleed it nicely. It's also a good way to get the fuel out as well.

late96
06-30-2015, 07:55 AM
Also be sure to bleed your line going to gauge once you get everything else bled out

ALF401
07-02-2015, 07:36 PM
I had s similar problem several years back. Turned out I had a bad connection inside the fuel cell. The fuel line was connected to the top of the fuel cell with a hose running down to the bottom of the fuel cell. Pump was pulling air from the pick up hose at the top of the fuel cell. The thing would idle fine but when the pump tried to pull more fuel it would just pull more air. Replaced the pick up hose and tightened the connection and everything was fine after that!