Classic/Antique Car Repair/1956 235 chevy carb

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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.

Classic/Antique Car Repair

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Brad Sears

Expertise

All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.

Experience

Automotive tech instructor. Syndicated auto columnist 1970's though the early 1990's. Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's TV Show "Last Chance Garage" 1980's PBS-TV syndicated. Auto instructor for the following companies: Fram Autolyte Holly Carter AMF Ford Motor University Of Conn Blue Hills Technical School Sugar River Technical Center Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.

Publications
Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.

Education/Credentials
More than I care to remember. Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.

Awards and Honors
Moto Award winner. And much more.

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