In 52 the model "B" carb was revised and the ball in the bottom of the accelerator pump well was eliminated along with the screen and passage for the pump. Look down the carb throat at the airhorn cross bar. If there are only two small holes in the center of the cross bar you have the revised carb. The carb should be mounted to the manifold using either a double thickness flange gasket or an insulator, but not both. There is a vacuum port on the bottom of the carb for the power jet. Make sure that port is not blocked off by the gasket. If it is you have the wrong gasket. If you use the insulator instead make sure it not upside down. The notches should be facing up.
