Flooding Holley
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,072
Likes: 331
From: Clear Lake Shores Texas
2016 C3 of Year Finalist
Flooding Holley
I had the original Holley carb for my 72 LT-1 rebuilt a few months ago after which it ran reasonably well. The car sat for a few months and when I started it last weekend after about 30 seconds gas started running out of the rear bowl vent and the engine stalled. I have changed out, one at a time, the rear float, the needle/seat assembly and the power valve. None of these helped. Does anyone have any suggestions?
Thanks.
Thanks.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
I had the original Holley carb for my 72 LT-1 rebuilt a few months ago after which it ran reasonably well. The car sat for a few months and when I started it last weekend after about 30 seconds gas started running out of the rear bowl vent and the engine stalled. I have changed out, one at a time, the rear float, the needle/seat assembly and the power valve. None of these helped. Does anyone have any suggestions?
Thanks.
Thanks.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,072
Likes: 331
From: Clear Lake Shores Texas
2016 C3 of Year Finalist
Melting Slicks
Joined: Oct 2003
Posts: 2,169
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From: Chapel Hill NC
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One time when I replaced a float I accidentally bent it resulting it moving freely when the bowl was off the carb but it would hit the metering plate when installed. Another time when I replaced the power valve the gasket was slightly askew, causing major flooding. Both times I fixed one problem but created another.
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
Until you get it sorted out you'd better be very careful not to have a cylinder fill up with raw fuel while turning the engine over. Not only is it not good for your rings to be washed with fuel, but you can experience a hydraulic lock. This is where the engine can't turn over because the fuel has filled a cylinder and been trapped with both valves closed. When it locks with the engine spinning it can hammer the rotating assembly, doing damage requiring a tear down. If you think you've dumped much raw fuel into the cylinders you can pull the sparks plugs to let the cylinders drain and dry out. Squirting a little oil into the plug holes before firing it up would help re-lube the cylinder walls with oil. Good luck.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,072
Likes: 331
From: Clear Lake Shores Texas
2016 C3 of Year Finalist
Until you get it sorted out you'd better be very careful not to have a cylinder fill up with raw fuel while turning the engine over. Not only is it not good for your rings to be washed with fuel, but you can experience a hydraulic lock. This is where the engine can't turn over because the fuel has filled a cylinder and been trapped with both valves closed. When it locks with the engine spinning it can hammer the rotating assembly, doing damage requiring a tear down. If you think you've dumped much raw fuel into the cylinders you can pull the sparks plugs to let the cylinders drain and dry out. Squirting a little oil into the plug holes before firing it up would help re-lube the cylinder walls with oil. Good luck.
Last edited by dan1495; Jun 12, 2015 at 05:45 PM.
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
I was worried about that too. At the first sign of gas coming out of the vent I would shut it down, remove the carb and soak up any residual gas in the intake with a rag. I have nother carburetor I am going to run until I figure this out. I'm going to change the oil and filter as a precaution. Thanks for the reply.
