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 clutch disc, which is pressed against the flywheel by the pressure plate.
The clutch disc is centered by the input shaft of the gearbox, with which it is connected by gearing (see illustration 1.0).
1.0 Basic parts of the clutch
1 - flywheel. The surface of the flywheel, to which the friction lining of the clutch disc adjoins, must be free of grooves, oil and grease. Pay attention to the tight fit of the centering pins.
2 - clutch driven disc. Do not change the mounting position. The clip for the damper springs must face the pressure plate. Attention! Clean the splines of the input shaft and the used clutch disc, remove corrosion
3 - pressure plate
4 - a bolt of fastening of a pressure disk with a head under a six-sided socket wrench. Tightening torque 25 Nm. Bolts tighten or loosen in a cross pattern.
The tightening torque of the disc bolts on vehicles with automatic clutch is 10 Nm.
When depressing the clutch pedal (clutch disengagement) hydraulic or mechanical pressure is exerted on the clutch fork lever, the clutch release bearing is pressed against the pressure plate spring.
As a result of this, the pressure plate is released and the clutch disc is no longer pressed against the flywheel.
The power circuit between the engine and gearbox stops.
The clutch drive for all MERCEDES A-class cars is hydraulic. The hydraulic clutch system runs on brake fluid and is supplied with it from a common brake fluid expansion tank.
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 clutch disc is a wear part, but it lasts an average of more than 100,000 km.
The degree of wear depends mainly on the load (trailer operation) and driving style. The clutch itself does not require maintenance, because. it is self-regulating.
MERCEDES A 190 vehicles, as well as all vehicles with a diesel engine, are equipped with a so-called composite flywheel, which consists of two interconnected disks. Such a flywheel has a torsional vibration dampening mechanism that reduces vibrations that occur during engine rotation, and also helps to reduce noise levels when the engine is running at low and medium speeds.