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Deceleration System: Description

This system is used to reduce emission levels during deceleration. The valve is activated by intake manifold vacuum and positions the throttle plate to prevent an overly rich mixture. The system is composed of a deceleration (Solex) valve, a vacuum unit, and 3 connecting hoses.

The deceleration valve contains a check ball, a vacuum diaphragm, a barometric compensating bellows, and 3 ports. The vacuum unit is simply an adjustable diaphragm with linkage to the carburetor throttle flap.