Objectives • Describe the basic clutch parts • Explain the operation of the clutch • Compare differences in clutch design • Describe the different methods of releasing the clutch
Pressure Plate • Pressure plate is cast iron plate – Part of cover assembly • Cover assembly is bolted to the flywheel – Clutch disc is wedged between pressure plate and flywheel – Space between pressure plate and flywheel is less than thickness of clutch disc – Engine and transmission are physically connected when clutch pedal released
Coil Spring Clutch • Pressure plate springs are preloaded when clutch cover assembled at factory – Springs are compressed further when cover assembly is bolted to flywheel – Clutch is engaged: pressure plate exerts 1000- 3000 pounds force on the disc – Disc worn out: ten percent more torque carrying capacity left in the clutch than engine can deliver
Clutch Cable • Some cars use a cable to operate the clutch – Adjustment remains the same as the engine moves – Develop friction and wear with repeated use • Linkage can push on clutch arm – Cable can only pull on it • Pivot point of fork – Must be on the outside of input shaft • Away from cable end