Throttle Positioner

Connected to carburetor throttle lever, it prevents throttle from fully closing during deceleration. Diaphragm of throttle positioner is controlled by vacuum from the vacuum chamber of the coasting valve. When engine speed decreases to 1200±50 RPM, control box de-energizes coasting valve solenoid. This shuts off vacuum to throttle positioner diaphragm and allows carburetor throttle lever to return to normal idling position.