Author Topic: fuel starvation  (Read 920 times)

Offline leanburn

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fuel starvation
« on: July 22, 2010 - 09:01:21 PM »
i recently removed my electric fuel pump and went back to mechanical and now i'm running out of fuel in the high rpm's. i read through some old posts and so far i have removed sending unit to make sure it was clean, i replaced the last 5 ft of the steel line cause it had a small kink, any rubber fuel line was replaced with fuel line that has that steel braided coating, tried with fuel cap off, blew through the line. what else could i try? it worked fine with the electric but that was obviously a band aid.
 it is a warmed over 340 with the stock 5/16 line, fuel filter is between pump and carb,  it was before the pump so i changed it but no didn't make a difference.  i haven't dropped my tank yet, is there anything else i can look at.




Offline moper

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Re: fuel starvation
« Reply #1 on: July 22, 2010 - 09:47:34 PM »
Have you actually seen the presssure drop off at high rpm? Might be worth it to rig up a filled gage so you can really see it. You should have plenty of fuel, but carb setup and float levels could make it seem like you're losing pressure.

Offline 422STROKER

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Re: fuel starvation
« Reply #2 on: July 22, 2010 - 10:25:44 PM »
Could be the ignition too.

Tom
Tom
12.77 @ 108.87 15" Street Drag radial tires 3.23 gear

Offline leanburn

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Re: fuel starvation
« Reply #3 on: July 22, 2010 - 11:56:41 PM »
i rigged up a gauge and taped it to the windshield.

Offline Chryco Psycho

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Re: fuel starvation
« Reply #4 on: July 23, 2010 - 02:31:14 AM »
you could try the high volume mechanical pump or use a mallory quiet electric pump

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Offline 73Chally

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Re: fuel starvation
« Reply #5 on: July 23, 2010 - 08:58:32 AM »
My guess would be you might need to change the float levels and possibly change the jets.  Did you have more pressure with the electric pump before you switched t the mechanical?

Offline leanburn

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Re: fuel starvation
« Reply #6 on: July 23, 2010 - 09:18:15 PM »
i had a steady 6 psi with the electric wich is the same as the mechanical. with the mechanical it's good in first, it starts to drop midway of second and in third she's at 0 psi by 5500 rpm.

Offline Chryco Psycho

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Re: fuel starvation
« Reply #7 on: July 26, 2010 - 09:16:02 AM »
you need more fuel flow than the mechanical pump is suppling so either get a High Volume mech pump or you need to go back to an electric , Mallory has the quietest pump

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