69 350/350 Carb Issue
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,188
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From: Tank sticker? I ain't got no tank sticker! I don't need no tank sticker! I don't have to show any stinking tank sticker!
69 350/350 Carb Issue
Here's a carburetor question for the group: 69 Corvette, 350/350. Q-Jet recently rebuilt, appropriate places sealed with Dev-Con, new gaskets, needle/seat assembly, etc, brass float height set carefully per specs (float not leaking and sunk). This car does NOT have what I believe was original equipment: a fuel return line back to the tank from the fuel filter. It has just one line from the fuel pump to a filter, then into the carb. The problem is fuel bubbling up through the air horn and accelerator pump, and leaking all over the manifold. I have twice checked float height and needle/seat assembly for function and tightness, the seat gasket is in place, and there is no leakage past the needle/seat when held down manually. Yet the float chamber is overfilling. Any ideas?
Le Mans Master
Joined: Jan 2006
Posts: 8,319
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
What kind of fuel pump do you have? is it new and related to your problem? im thinking fuel pressure may be too high, buty Lars is the reputed forum Guru on Carbs, shoot him a message
tim
tim
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,188
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From: Tank sticker? I ain't got no tank sticker! I don't need no tank sticker! I don't have to show any stinking tank sticker!
69 350/350 Carb Issue
Tim
It has a new stock fuel pump from major Corvette parts vendor so presume it is in the 7 psi range.
It has a new stock fuel pump from major Corvette parts vendor so presume it is in the 7 psi range.
Melting Slicks
Joined: Jun 2001
Posts: 2,340
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From: Moro IL
I'm thinking along the same lines as everyone else, either your running too much fuel pressure overcoming the needle and seat assembly or the float for one reason or another isn't able to hold enough pressure on the seat to keep it from overfilling.
Pat Kunz
Pat Kunz
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,188
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From: Tank sticker? I ain't got no tank sticker! I don't need no tank sticker! I don't have to show any stinking tank sticker!
To answer questions - yes there is a vented cap and things were fine until the carb was rebuilt. Hot or cold it leaks fuel.
Thanks
Thanks
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Le Mans Master
Joined: Jan 2006
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
this may sound silly
Originally Posted by SILENT BOB
To answer questions - yes there is a vented cap and things were fine until the carb was rebuilt. Hot or cold it leaks fuel.
Thanks
Thanks
). Is it possbile by not having it its causing your problem?Just a thought
tim
Intermediate
Joined: Apr 2005
Posts: 38
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From: Antelope Valley CA
Did you put the wire clip of the needle into any of the holes in the float? I believe the clip is not supposed to do this, it just hangs on the bar of the float without going into any hole.
