The figure shows the vacuum clutch mechanism. Such a clutch uses the prevailing vacuum from the motor manifold to function the clutch. The vacuum clutch includes a reservoir, non-return valve, vacuum cylinder with piston, and solenoid valve.  Together with your motor vehicle idling, pay attention to get a growling sounds https://clutch-kereta75307.blogproducer.com/39937843/new-step-by-step-map-for-clutch-plate