All models with a manual transmission are equipped with a dry single-plate clutch, which consists of a driven and pressure clutch disc, a diaphragm spring, a casing and a clutch release bearing. The pressure disc has an adjusting ring that ensures self-adjustment of the clutch as it wears (see illustration 1.0). This clutch received the designation SAC from the first letters of the English name "self-adjusting clutch".
The pressure plate is rigidly screwed to the flywheel, which in turn is flanged to the engine crankshaft. Between the pressure plate and the flywheel is the driven clutch disc, which is pressed toward the flywheel by the pressure plate. The driven clutch disc is firmly connected to the primary shaft of the gearbox by a splined hub.
The driven clutch disc moves freely on the splines of the primary shaft of the gearbox and is pressed against the flywheel by the pressure plate with the force created by its membrane spring. Friction linings are riveted on both sides of the driven disc. The driven clutch disc is firmly connected to the primary shaft of the gearbox by a splined hub.
When pressing the clutch pedal (clutch release) hydraulic pressure is applied to the clutch release fork lever and the clutch release bearing is pressed against the pressure plate diaphragm. As a result, the pressure plate is released and the driven clutch disc is no longer pressed against the flywheel. The power connection between the engine and gearbox is broken (see illustrations 1.0a, 1.0b and 1.0v).
The clutch release bearing is mounted on the front side of the gearbox and is moved by the clutch release fork. When the clutch pedal is pressed, the piston in the master cylinder moves and squeezes out brake fluid, which flows through the hose to the clutch slave cylinder. Under the pressure of the fluid, the piston of the clutch slave cylinder moves and activates the clutch release fork. The clutch release fork moves the bearing, which acts on the spring of the pressure plate and presses the pressure plate away from the slave disk of the clutch.
Each time the clutch is engaged and disengaged, the friction lining of the clutch disc gradually wears out as a result of friction. Thus, the driven clutch disc is a wearing part, but it lasts on average for more than 100,000 km. The degree of wear depends mainly on the load, for example, operation of the car with a trailer and on the driving style.
All engines are equipped with a so-called composite flywheel, which is two disks connected to each other. Such a flywheel has a damping mechanism (depreciation) torsional vibrations that occur when the engine rotates and helps reduce noise levels when the engine is running at low speeds.
In addition, on cars with a demultiplier, to prevent so-called peak loads caused by abrupt release of the clutch pedal, a special valve with the designation PTL (an abbreviation of the first letters of the English name of the valve, translated as "peak load limiter") is installed on its hydraulic drive. When the clutch pedal is released, the valve closes and the brake fluid goes through the bypass hole on it. This slows down its flow and the driven disk connects more smoothly to the flywheel (see illustration 1.0g).