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Vacuum Switch: Description and Operation


Description

The 4 inch Hg vacuum switch is controlled by carburetor ported vacuum and has a normally closed electrical contact that indicates a closed throttle condition. The switch is opened by a 4 inch Hg vacuum level.

The 10 inch Hg vacuum switch is controlled by manifold vacuum. When open, the switch indicates a deep throttle condition, a non-cruise engine operating condition.