The diameter of the clutch discs and the pressing force of the driven disc depend on the engine power. Not all car models are equipped with a clutch of the same design. For this reason, when ordering spare parts, please state the engine type and number. The diameter of the clutch discs may also vary depending on the vehicle model.
The clutch consists of the following main units:
- A) clutch actuator, which includes the clutch pedal, clutch cable with automatic adjustment, clutch release fork and release bearing;
- b) the clutch itself, located in the crankcase and including a pressure plate, a driven disc and friction linings that engage with the flywheel.
When you press the clutch pedal, the clutch cable is pulled and the clutch release lever presses the release bearing against the diaphragm spring. The pressure plate moves away from the flywheel, and the driven disc is no longer squeezed out to the flywheel and rotates freely. In this way, the power circuit between the engine and gearbox is disconnected.
As soon as the clutch pedal is released, the diaphragm spring returns the pressure plate to the flywheel, thereby pressing the driven disc and restoring the power circuit.
slippage (slippage) clutch becomes noticeable only when driving in high gear. At the same time, the effective engine power is maximum. In this case, the engine speed is higher than necessary for the selected gear. When starting off, slipping of the clutch is almost imperceptible. The consequence of such a malfunction may be abrasion of the surface of the driven disk, the working surface of the pressure disk and the flywheel. Usually, when replacing the driven disk, the pressure disk must also be updated.
A good clutch should pass the next test without any problems.
1. Apply the parking brake.
2. Engage third gear by depressing the clutch pedal
3. Depress the accelerator pedal and slowly release the clutch pedal. The engine should shut down.
If, when depressing the clutch pedal to change gear, noises resembling crackling or scratching are heard, this means that the clutch is not disengaging well. It is recommended that you first check the position of the mat on the floor under the clutch pedal. It is possible that it has shifted and is limiting the travel of the clutch pedal.
Attention! If, when shifting gears on a car with a manual gearbox, the driver makes a mistake and, for example, shifts from 5th gear to 2nd, then the speed of rotation of the clutch driven disk is higher than the speed of rotation of the engine crankshaft. In such a situation, 2nd gear should not be engaged for some time. The increase in engine speed can be increased by synchronizing rings. However, due to the particularly high speed with which the pressure plate rotates, the friction lining may break, parts of which clog under each other, thereby increasing the thickness of the driven disc to unacceptable sizes. In this case, the clutch pedal may be fully depressed, but the clutch will not disengage or will not fully disengage.
If the car moves jerkily, this means that the transmission of torque from the engine is uneven. The reasons for such a malfunction may be different.
- A) Defect or weakening of the engine or transmission mount and as a result of the engagement of the clutch, the power unit begins to vibrate.
- b) The friction lining on the driven disk is burned or hardened. This is possible as a result of clutch overload.
- G) The pressure plate is bent or its working surface is warped.
- d) The surface of the flywheel has been deformed, and irregularities in the form of waves have formed on it.
Attention! Clutch replacement is only possible when the engine or gearbox is removed. The pressure plate, driven plate and release bearing must be systematically updated. Replacing the clutch cable requires adjustment of the cable tension adjustment mechanism, especially in cases where the cable breaks. It is recommended to entrust the replacement and adjustment of the cable tension to a workshop.