The Rochester Model B carburetor was used primarily on 4 and 6 cylinder General Motors products from 1950 to 1967. It was also sold as a service replacement for the 1932 and up Carter or Stromberg carburetors on Chevrolet engines.
The first design used a leather accelerator pump with a flat, slotted stem. These were used on Chevrolet cars up to 1956 and trucks to 1962.
The second design, from 1957 onwards in cars and 1963-up in trucks uses a round stem pump with a rubber cup.
Depending on the type of choke employed, the carbs were designated B, BC or BV. The plain model B was the manual choke version. BC carbs used a choke thermostat mounted on the side of the carburetor - attached to the air horn (top third). BV carburetors used a crossover choke where the choke coil is mounted on the manifold in a heat stove.
Carburetor Numbers
Early carburetors had the number on a triangular brass tag. Later models used an aluminum tag. Model B carbs were not stamped with the carburetor number, though the last 4 digits of the carb number may have been stamped on a protruding edge of the original factory airhorn gasket.
Rochester carburetors listed by carburetor number
Rochester Model B Articles
More detailed information on Rochester Model B versions, parts and master kits