Re: Anti puddle valve

Posted by John Sauser On 2010/7/30 10:33:48

The manifold drain was on the prewar engines. I have 3 356 cars and none has that drain, and there is no provision for it. I also have 3 pre war engines, 32 and 35 std 8 which do have it so I do know what I am looking at.

The drain was for draining fuel that had acumulated in the manifold if the car was started and then shut off before the engine and intake got up to operating temperature.

When a cold engine is started the fuel is not fully vaporized and the droplets will form puddles in the cold intake manifold, if the engine is shut down at this time the liquid fuel will drain out. If the engine is brought up to operating temperature the manifold will warm up and this puddled fuel will vaporize and be carried into the cylinders and burned. If there is any fuel coming out of the drain after the engine has been run up to temperature then carburetor has a problem as fuel should not run into the manifold when the engine is shut down.

John

Edit: The 32 doesn't have the drain as it has an up draft carb.