1957 Cadillac carburetor/fuel trouble

[Johan Boltendal]

  Hi 

 

A 1957 Cadillac with a 4 barrel Rochester is flooding the engine under braking due to fuel coming out of the two vent pipes on top of the carb,. My friend is a mechanic and into old cars rather well.

Knows his carburetors and has tried several option to get grip on the situation, without result . Most knowledge is with German made carbs as you will understand. But then that should not be that big a difference.

He concluded that the fuel, under braking,is coming out of the two vents on top of the carb, flooding the engine.It kind of builds up and find it's way out into the secondary part.Float level is by the book float are tight and the car is running well till the brakes are applied and the fuel spill starts.  Could there be a plate/part or gaskets missing, that prevents this fuel escape under braking ? Thanks for your attention to this question    Johan

[carbking]

GUESSING!

 

Rochester used what was called a "balance spring" to add additional pressure to the float's buoyancy. I would check to make certain some previous rebuilder did not remove the spring; and if the spring is present, that the tang on the float is resting against the spring in such a manner that the spring is actually supplying pressure.

 

Jon.

[Johan Boltendal]

Good morning Jon,  thank you spot on , both springs missing, there is a spare carb , with the owner, let's find out of they are present within that one, if not can you supply them or have a source? regards Johan