How to Assemble the Throttle Body Shaft for Carter BBD Carburetors

The Carter BBD two-barrel carburetor was used from the 1950s through the 1980s, mainly on DeSoto, Chrysler and Jeep products with six-cylinder or small-block V8 engines. As the name implies, the BBD has two barrels, or fuel circuits that deliver fuel to the engine. The airflow is controlled by two throttle plates that are attached to the throttle shaft.

Instructions

1

Slide the throttle shaft through the left-hand, or drivers side, of the carburetor body. You want the threaded end of the shaft to be sticking out of this end of the body.

2

Turn the carburetor over, so you are looking at the bottom. The carburetor has two holes in it, where the throttle-plates sit. The throttle shaft has two slots in it that the throttle-plates slide through, and each slot has two screw holes in it. Turn the shaft so the threaded ends of the screw holes are facing away from you.

3

Turn the shaft in a clockwise direction until the slots are facing you.

4

Look at the throttle plates. They have two holes in them that match the screw holes in the throttle shaft. The edges of the plates are beveled at a 45-degree angle. They only go in one way. Hold the throttle plate so the short edge, where the bevel starts, is facing into the carburetor and toward the threaded holes in the throttle shaft.

5

Slide the throttle plate into the shaft. Line up the holes. Turn the shaft in a counterclockwise direction, so the throttle-plate sits against the sides of the carburetor body. The bevel on each side of the throttle plate should fit flush against the carburetor body and the screw holes should be facing you. If not, take out the plate, turn it over and put it back in. Install and tighten the two screws with a small flat-head screwdriver. Repeat for the other plate.