How Much Do You Know About Vacuum Clutches Vacuum clutches use the existing vacuum in the engine manifold to operate the clutch. The vacuum clutch consists of an oil tank, a check valve, a vacuum cylinder with a piston, and a solenoid valve.
When the throttle valve is open, the pressure in the intake manifold increases as a result of which the valve check valve closes. It separates the reservoir and manifold so there is always a vacuum...