Carburetor - Carter BBD 2-Bbl: Description

The Carter BBD carburetor is a 2-barrel downdraft model. The BBD has four basic fuel metering systems. The float (fuel inlet) system, idle (low speed) system, accelerator pump system and the main metering (high speed) system.

The float system maintains fuel level. The idle system is used for idle and initial part-throttle operation. The main metering system is used for part-throttle and cruise operation. The pump system provides additional fuel during acceleration.

An electric choke with a choke diaphragm is used. A stepper motor is used to control air flow in metered air bleeds in the main fuel metering circuit. A Solevac vacuum solenoid is used to keep idle speed constant when load is placed on engine.