Gas leak help
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Joined: Oct 2012
Posts: 86
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From: Lucas TX
Gas leak help
i just picked up a 76 4 speed that is going to need some help. First problem is a fuel leak at the carb. Last owner put a EB 1411 on a EB intake and added an electric fuel pump after the mechanical in the engine bay. There is some sort of pressure regulator before the carb. The carb wll leak 3 drops then pause then 3 drops again at rear of carb on PS. Would too high a pressure cause it to leak? Any other ideas?
Le Mans Master
Joined: Oct 2006
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From: Gladstone MO
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Having an electric pump after the mechanical is pretty much a wasted effort. A mechanical pump will supply all the fuel needed until you get into some really big horsepower.
Your leak may be as simple as a fitting needing an o-ring replaced, or a galled fitting that is seeping. I'd look at taking the electric pump and regulator off, re-plumbing as necessary, and then chasing any leaks.
If the fittings installed are flare type fittings, it could be that a flare on a tube is cracked, or the PO mixed automotive 45* flares and -AN type that are 37*. THe automotive 45* flares are designed to be a double flare- that is the end of the tube is upset with a die, and then folded back in on itself making a double wall in the seat.
Your leak may be as simple as a fitting needing an o-ring replaced, or a galled fitting that is seeping. I'd look at taking the electric pump and regulator off, re-plumbing as necessary, and then chasing any leaks.
If the fittings installed are flare type fittings, it could be that a flare on a tube is cracked, or the PO mixed automotive 45* flares and -AN type that are 37*. THe automotive 45* flares are designed to be a double flare- that is the end of the tube is upset with a die, and then folded back in on itself making a double wall in the seat.
Thread Starter
Advanced
Joined: Oct 2012
Posts: 86
Likes: 2
From: Lucas TX
Thanks. Though I have only had it a few days, I keep finding lots of bubba fixes. Two fuel pumps was the most obvious. He did not use hard lines, so he didn't mix AN and double flair. He used some type of clear tubing and clamps. Removing the electric pump will be my first move. It does not seem to be leaking from the fittings, though. I see gas pooling inside the rear of the carb and leaking out the side.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
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Going to hard lines will possibly save your car. Even the braided lines like the ones everyone likes are a bit spooky to me. In avaition, the braided lines that carry fuel are coverd with a sleeve so that IF they leak, the leak can be contained and not spray onto something hot.
If the float level is too high, the level of fuel in the carb can be up to the point that it could leak thru the gaskets. Without seeing it, it's hard to say where it's really coming from. Looks like you've got a project on your hands. Get the fuel problems solved, get it running good and enjoy.
If the float level is too high, the level of fuel in the carb can be up to the point that it could leak thru the gaskets. Without seeing it, it's hard to say where it's really coming from. Looks like you've got a project on your hands. Get the fuel problems solved, get it running good and enjoy.
