carb\fuel pump question

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Shippee123
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carb\fuel pump question

Postby Shippee123 » Sun May 15, 2016 9:19 pm

Im trying to adjust and tune my motor so I can take it for a test drive tomorrow. I found that when I rev the motor up to 2400 rpm it starts falling off after a few seconds. I have an air tech in line pump mounted at bottom of the tank. Is this enough of a pump for a stock 454 with a rv cam and a Holley 650 with vacuum secondary's? I am not a carburetor person but it seems that once it revved up to a certain rpm the pump would be what would make it start falling off.

Thank You for any input you can provide. Itchinching for a test ride but I want it to be right first.
Art
11'6"x7' Royal craft with a 0300a Continental swinging a 74"two blade Super Snapper

One Eyed Gator
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Re: carb\fuel pump question

Postby One Eyed Gator » Mon May 16, 2016 8:16 am

Put a fuel pressure gauge on it you will know for sure.

Rich Andrews
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Re: carb\fuel pump question

Postby Rich Andrews » Mon May 16, 2016 10:59 am

This problem you are having can cause you to rebuild your motor if u don't figure it out. I'd start off w a pressure gauge,and maybe run some additional fuel line before your pump not after to build up more fuel capacity in the fuel line so that it doesn't need to suck more from the tank and deliver it straight up to the carb.

That 650 may be the problem as well.
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Shippee123
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Location: Paisley,fl

Re: carb\fuel pump question

Postby Shippee123 » Mon May 16, 2016 9:04 pm

Finally found the problem. My new fuel hose apparently was full of dirt dobbers from Napa. Had meal worms in fuel water separator as well as after it . Carb fuel inlets were severely stopped as well. New needle and seats and some line flushing and it is up and running .
Still have some prop tweaking to do and should work great.

Thanks for the input.

Art
11'6"x7' Royal craft with a 0300a Continental swinging a 74"two blade Super Snapper


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