Float Level 1954 Carbs-Leaking-Help
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
Float Level 1954 Carbs-Leaking-Help
I just put kits in the carbs and set the float level to 1/2" and on running car does great.Purrs like a kitten but when you shut it off with the engine warm the carbs leak.I talked to MaryJo and she said this is normal but there was a bullitin from GM on how to fix this.I could see a tiny dribble that would be caught by the air cleaner.In this case the fuel is enough it finds its way to the pavement.I've noticed other applications for this carb set the float lower like 3/4" is this the common fix?Thanks in advance.
Race Director
Joined: Apr 1999
Posts: 10,866
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From: Beverly Hills/Pine Ridge Florida
I'd set the floats lower for starters.
Did you use the correct needle valves? They're the 3 piece needle valves, consisting of the valve itself, a spring, and a little pin that goes inside the needle valve itself.
Is there "junk" in the seat area preventing closure?
Chuck
Did you use the correct needle valves? They're the 3 piece needle valves, consisting of the valve itself, a spring, and a little pin that goes inside the needle valve itself.
Is there "junk" in the seat area preventing closure?
Chuck
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
Thanks Chuck I'm in the process of lowering the level now.No junk in seat area.These neeedles and seats came in a kit from MaryJo Rohner and they are the 3 piece units.I was going to set the floats at the Corvair level which is 3/4 but I'm not sure the float will drop far enough to even open.I'll report back -Thanks again.
Le Mans Master
Joined: Feb 1999
Posts: 5,840
Likes: 376
From: Mobile AL
From "The Corvette Restorer", I think.
The fix I used is drilling .030" bleed-back holes inside the fuel pump next to the check valves, one on the inlet side and one on the discharge side.
This absolutely works. It allows the heat-expanded gasoline to return to the tank. The holes are so small that they don't affect pump efficiency while the engine is running.
You can leave your float levels stock.
This absolutely works. It allows the heat-expanded gasoline to return to the tank. The holes are so small that they don't affect pump efficiency while the engine is running.
You can leave your float levels stock.
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
The fix I used is drilling .030" bleed-back holes inside the fuel pump next to the check valves, one on the inlet side and one on the discharge side.
This absolutely works. It allows the heat-expanded gasoline to return to the tank. The holes are so small that they don't affect pump efficiency while the engine is running.
You can leave your float levels stock.
This absolutely works. It allows the heat-expanded gasoline to return to the tank. The holes are so small that they don't affect pump efficiency while the engine is running.
You can leave your float levels stock.
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I think the float level did the trick(knock on wood).The carbs are dry at this point.Thanks Chuck,Jerry and Mike.
Jerry I went and opened the other pump up.Do you drill into the aluminum edge of the check valve or through the pump body?I'm not totally sure where to drill if your meaning the body of the pump.I think if I drill the edge of the check valve I can get over far enough towards the center that the gasket under the valve will not seal it back up.
Jerry I went and opened the other pump up.Do you drill into the aluminum edge of the check valve or through the pump body?I'm not totally sure where to drill if your meaning the body of the pump.I think if I drill the edge of the check valve I can get over far enough towards the center that the gasket under the valve will not seal it back up.
Le Mans Master
Joined: Feb 1999
Posts: 5,840
Likes: 376
From: Mobile AL
Roger, if you'll e-mail a photo of your pump check valve area to me at jerrybramlett@comcast.net, I'll try to help.
Safety Car
Joined: Jul 2006
Posts: 4,606
Likes: 210
From: Nevada City Ca.
2015 C1 of Year
I'd set the floats lower for starters.
Did you use the correct needle valves? They're the 3 piece needle valves, consisting of the valve itself, a spring, and a little pin that goes inside the needle valve itself.
Is there "junk" in the seat area preventing closure?
Chuck
Did you use the correct needle valves? They're the 3 piece needle valves, consisting of the valve itself, a spring, and a little pin that goes inside the needle valve itself.
Is there "junk" in the seat area preventing closure?
Chuck
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Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Race Director
Joined: Apr 1999
Posts: 10,866
Likes: 717
From: Beverly Hills/Pine Ridge Florida
The 3 piece needle valve is Corvette. The solid needle valve is Corvair.
Back in the old days, when you got carb kits, you got both. You also got 2 different lid gaskets, one Corvair, one Corvette.
Gotta use the right lid gasket too. Chuck
Back in the old days, when you got carb kits, you got both. You also got 2 different lid gaskets, one Corvair, one Corvette.
Gotta use the right lid gasket too. Chuck
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Thanks I checked the sight and its nice.I wish I would have known earlier.I paid 39.95 for each carb kit and theirs is 26.50.
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I had to trim the lid gaskets-looked like they stamped too many at one time.Hopefuly I wont have to do these carbs for another 5 years or so.
