The determine demonstrates the vacuum clutch system. This sort of clutch works by using the existing vacuum from the motor manifold to work the clutch. The vacuum clutch is made up of a reservoir, non-return valve, vacuum cylinder with piston, and solenoid valve.  To understand how a clutch is effective, https://clutch-plate80368.azzablog.com/33180340/5-essential-elements-for-clutch-plate