Classic/Antique Car Repair: 1956 235 chevy carb, ford carburetors, diaphragm type

Question
Stock 235 with a rodchester carb, Runs rich and fouls plugs in minutes. Soaked in carb cleaner, new gaskets, same thing. (manual choke is open) Floats set per specs. Don't know how to check what I believe is the power valve ( a rod pushing thru a jet that is ball bearing and spring loaded) Any help appreciated. Thanx

Answer
It does not sound like the power valve is causing the problem. In the Ford carburetors the power valve is a diaphragm type and will cause this but not in a Rochester. I would look at the float to see if it is a problem. If the carburetor is equipped with the old brass float, hold it up to your ear and shake it. If it is leaking it will have gas in it and you can hear it slosh. If the float is leaking it will sink and cause too much fuel to enter the float bowl. If the float is the black composition they get porous with age and then will sink and cause too much fuel or a high fuel level in the float bowl and cause rich condition as well. The  brass float can be soldered once you find the hole. I usually hold the float in a small pin vise and heat under it with a match. The fuel will heat up and the form a small jet flame at the hole. Once found a small drop of solder or even some J B epoxy will seal the hole.