Clutch details: 1 - slave disk; 2 - pressure plate assembly (basket); 3 - clutch release slave cylinder assembly with release bearing
In a car with a manual transmission, the clutch release drive is hydraulic.
The clutch consists of a basket (pressure plate assembly) and the driven disk. The basket is a steel casing in which a pressure disk is installed. From the casing side, the disk is pressed by a diaphragm-type pressure spring. The clutch basket is attached to the flywheel with six bolts. A driven disk is installed between the pressure plate and the flywheel.
Friction linings are riveted to both sides of the driven disk. To dampen torsional vibrations at the moment the clutch is engaged, a damper with cylindrical springs is built into the driven disk. The driven disk hub engages splined with the primary shaft of the gearbox.
The hydraulic clutch release drive consists of the master and slave clutch release cylinders, connected by a pipeline.
Clutch hydraulic drive
The pipeline supplies pressure to the working cylinder, which in turn transmits force to the central diaphragm clutch spring through the clutch release bearing. The clutch slave cylinder is assembled into a single unit with a release bearing (in spare parts catalogs both of these names are used to designate the part) and installed in the clutch housing.
Brake fluid is used as the working fluid in the clutch hydraulic drive. It enters the clutch master cylinder through a hose from the brake master cylinder reservoir. For this purpose, a branch pipe is made on the left side of the tank.
The working fluid in the hydraulic clutch release system must be replaced regularly in accordance with the maintenance schedule (see "Maintenance plan").
Malfunctions of the clutch master and slave cylinders include: wear of the clutch master cylinder seals; leakage of working fluid at the joints of tubes and fittings and from under the piston cuffs of the cylinders.
Note: If the working cylinder is not tight, brake fluid will leak from underneath the clutch housing. The presence of oil leaks in the same place is caused by wear of the gearbox input shaft seal. You should also check the clutch hydraulic hose and pipe to make sure they are not cracked, cut or otherwise damaged. We replace faulty parts.
Correct operation of the hydraulic clutch release drive is only possible if there is no air in the system, which could prevent the clutch from disengaging completely. As a result, gear shifting will be difficult or impossible. Air can enter the system when the fluid level in the master cylinder reservoir drops below the permissible limit, as a result of a breach in the tightness of the connections.
The tightness must be restored by replacing damaged parts. To remove air, simply bleed the clutch release hydraulic drive. The bleed nipple is made in the tip of the hydraulic drive tube.
On the automated manual transmission 2182 (AMKP), instead of a hydraulic clutch release drive, a mechanism with an electric drive is installed.
The electric drive acts directly on the clutch fork. The clutch release fork rests on a support with a ball end. When the fork is turned, the force is transmitted to the petals of the pressure spring through a radial thrust ball bearing (release bearing). The bearing is mounted on the clutch release sleeve, through which it contacts the clutch release drive fork.
Due to the absence of a gap in the clutch release drive, constant pressure of the clutch against the petals of the pressure spring is ensured, while the release bearing operates continuously. The bearing is lubricated for its entire service life. The clutch release sleeve moves along a guide sleeve placed on the input shaft of the gearbox and attached to the clutch housing with three bolts.
A worn release bearing will produce increased noise during operation. When replacing clutch discs, the manufacturer recommends replacing the release bearing, regardless of its condition. This is justified if the car's mileage is about 100 thousand km or more. But if the clutch disc has worn out over a significantly shorter mileage (30-40 thousand km), then this is most likely the result of improper operation of the car. In this case, there is a high probability that the release bearing has retained sufficient service life for further use. However, when replacing the clutch discs, you should check the condition of the bearing: if its outer ring sticks when rotating, there is play or noise is heard, the release bearing must be replaced.