Clutch: Description and Operation

The clutch is a diaphragm-spring clutch of a dry single disc type. The diaphragm spring is of a tapering finger type, which is a solid ring in the outer diameter part, with a series of tapered fingers pointing inward.

The disc, carrying four torsional coil springs, is positioned on the transmission input shaft with an involute spline fit.

The clutch cover is secured to the flywheel, and carries the diaphragm spring in such a way that the peripheral edge of the spring pushes on the pressure plate against the flywheel (with the disc in between), when the clutch release bearing is held back. This is the engaged condition of the clutch.

Depressing the clutch pedal causes the release bearing to advance and pushes on the tips of the tapered fingers of the diaphragm spring. When this happens, the diaphragm spring pulls the pressure plate away from the flywheel, thereby interrupting the flow of drive from flywheel through clutch disc to transmission input shaft.

The clutch pedal position switch is mounted above clutch pedal. This switch is in the electric circuit of starting motor, and operates according to movement of clutch pedal. When starting the engine, the clutch pedal should be fully depressed in order to turn on this switch. If the clutch pedal is released or is not depressed all the way, this switch is OFF and the starting motor will not run even if the ignition key is in the START position.