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  #1 (permalink)  
Old 04-25-2014, 07:44 AM
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Default Webers weeping

On 3 of the carbs one barrel of each carb is dripping fuel into the barrel after the motor us shut off. This is a new problem... Anyone know whats going on?
Jon
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Old 04-25-2014, 07:53 AM
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Quote:
Originally Posted by saltshaker View Post
On 3 of the carbs one barrel of each carb is dripping fuel into the barrel after the motor us shut off. This is a new problem... Anyone know whats going on?
Jon
User error, I suggest a Holley 650DP
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Old 04-25-2014, 09:33 AM
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There are several potential causes for this type of problem if you have not experienced it previously. 1) Fuel pressure regulator malfunctioning and increased pressure seen at the carbs, 2) Different gas formulation with increased content of alcohol resulting in fuel percolation after hot shut down, or 3) Higher ambient temperatures than previously experienced.

Since you mentioned that 3 out of the 4 carbs are exhibiting the symptoms, I have assumed that it is not a mechanical problem inside the carbs or foreign matter getting into your float seats.

Let me know if it is any of these causes. Just curious.

John
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Old 04-25-2014, 10:54 AM
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It's that garbage they sell for gasoline these days with the Ethanol in it. The gas with Ethanol has a lower boiling point than pure gasoline, so in a short "hot soak" the gas with Ethanol boils and percolates out of your carburetors, dripping raw fuel into your cylinders.

The effect can be minimized by using marina gas (it has no Ethanol) mixed with race gas. So far, 90 octane is the hottest marine fuel I can get around here, so I mix that about 75/25 with 108 octane race fuel - seems to help. Didn't have this problem back in Detroit when I could get gasoline that was not watered down with Ethanol.

You might also try opening your hood immediately after a run, and leave it open for awhile while the engine cools down. My next trick will be installing the phenolic spacers I bought for my Webers years ago.

Jeff
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Old 04-25-2014, 03:32 PM
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Default Your Right!

Ethanol ate the fuel line and the needle seats had to be cleaned....
Thanks
Jon
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Old 04-25-2014, 05:03 PM
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Quote:
Originally Posted by saltshaker View Post
Ethanol ate the fuel line and the needle seats had to be cleaned....
Thanks
Jon
See, user error
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Old 04-25-2014, 11:50 PM
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Quote:
Originally Posted by saltshaker View Post
Ethanol ate the fuel line and the needle seats had to be cleaned....
Thanks
Jon
Are you going to replace all your fuel hoses now Jon?
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Old 04-26-2014, 05:01 AM
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Default Fuel lines

Yes, i had hard lines to the pump and replaces all of them after the pump
Jon
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