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lutch Faults The following are the main faults: Slip — failure of the surface to grip resulting in the driven plate revolving slower than the engine flywheel : Clutch gets hot and emits an odor. Spin or drag — failure of the plates to separate resulting in noise from the gearbox when selecting a gear: most noticeable when the vehicle is stationary. Judder — a vibration which occurs when the clutch is being engaged , . when the vehicle is stationary. Fierceness — sudden departure of the vehicle even though the pedal is being released gradually. E The Clutches( supplementary contract) A clutch is a friction device used to connect and disconnect a driving force from a driven member. In automotive applications, it is used in conjunction with an engine flywheel to provide smooth engagement and disengagement of the engine and manual transmission. Since an internal bustion engine develops little power or torque at low rpm, it must gain speed before it will move the vehicle. However, if a rapidly rotating engine is suddenly connected to the drive line of a stationary vehicle, a violent shock will result. So gradual application of load, along with some slowing of engine speed , is needed to provide reasonable and fortable starts. In vehicles equipped with a manual transmission, this is acplished by means of a mechanical clutch. The clutch utilizes friction for its operation. The main parts of the clutch are a pressure plate, and a driven disk. The pressure plate is coupled with the flywheel, while the driven disk is fitted to the disk by the springs so that the torque is transmitted owing to friction forces from the engine to the input shaft of the transmission. Smooth engagement is ensured by slipping of the disk before a full pressure is applied. The automobiles are equipped with a dry springloaded clutch. The clutch is termed “dry” because the surfaces of the pressure plate and driven disks are dry in contrast to oilbath clutches in which the plate and disks operate in a bath of oil. It is called “springloaded” because the pressure plate and the driven disk are always pressed to each other by springs and are released only for a time to shift gears or to brake the automobile. In addition to the plate and disk, the clutch includes a cover, release levers, a release yoke, pressure springs and a control linkage. The clutch cover is a steel stamping bolted to the flywheel. The release levers are secured inside the cover on the supporting bolts. The outer ends of the release levers are articulated to the pressure plate. Such a construction allows the pressure plate to approach the cover or move away from it, all the time rotating with the cover or move away from it, all the time rotating with the flywheel. The springs spaced around the circumference between the pressure plate and the clutch cover clamp the driven disk between the pressure plate and the flywheel. The springs are installed with the aid of projections and sockets provided on the cover and pressure plate. The pressure plate sockets have thermalinsulation gaskets for protecting the springs against overheating. The clutch release mechanism can be operated either mechanically or hydraulically. The mechanicallyoperated release mechanism consists of a pedal, a return spring, a shaft with lever, a rod m release yoke lever, a release yoke, a release ball bearing with support and a clutch release spring. When the clutch pedal is depressed, the rod and shaft with yoke shift the release bearing and support assembly. The release bearing presses the inner ends of the release levers, the pressure plate is moved away from the driven disk and the clutch is disengaged. To engage the clutch ,