The clutch Hydraulic Release Bearing, also known as hydraulic clutch release bearing or hydraulic slave cylinder, is a key component in the clutch system of a manual transmission vehicle. Its main function is to act as an interface between the hydraulic system and the clutch mechanism, replacing the mechanical linkage used in conventional clutch systems.

During the working process of the clutch hydraulic release bearing, the following are its main functions and features:

1. Hydraulic action: when the driver depresses the clutch pedal, the master cylinder (clutch master pump) generates hydraulic pressure, and this pressure is transmitted to the clutch hydraulic release bearing through the oil pipe.

2. Clutch Separation: As the hydraulic pressure builds up, the release bearing moves forward and pushes the pressure plate, which causes the clutch disc to separate from the flywheel so that the engine power is not transmitted to the wheels and the driver can shift gears smoothly.

3. Precision and Durability: Designed for high-precision operation, this bearing ensures smooth release and engagement of the clutch, and is generally more durable than mechanical bearings because it reduces the wear caused by direct mechanical contact.

Advantages of hydraulic release bearings for clutches include reduced operator force, space-saving compact design, improved reliability, and ease of installation and maintenance. It is used in a wide range of applications for a variety of cars, trucks and heavy machinery with manual transmissions.

Methods of checking the degree of wear of hydraulic separation bearings

To check the degree of wear of the separation bearing, the following methods can be taken:

1. Appearance inspection:

Mainly check the shell of the separation bearing for wear, scratches or cracks. These cosmetic damages may indicate that the bearing has experienced more severe wear.

Check the grease or lubricant of the bearing for leakage or contamination, which may also be an indication of bearing wear.

2. Sound check:

Listen carefully to the sound the release bearing makes while the vehicle is running or being tested. Under normal conditions, the release bearing should be noiseless. If there are rattling, knocking or rubbing noises, these could be signs of bearing wear or damage.

3. Temperature check:

Use a tool such as a static tester or infrared thermometer to check the temperature of the separation bearing. If the temperature of the bearing is abnormally high, it may be due to poor internal lubrication or increased friction, which is usually associated with bearing wear.

4. Friction check:

Where conditions permit, the release bearing can be checked for friction during clutch engagement and disengagement. If the friction is excessive or erratic, it may be an indication of bearing wear. Please note, however, that this method may require specialised equipment and skills.

5. Clearance check:

Check whether the clearance of the release bearing exceeds the specified range. Too much or too little clearance may lead to bearing damage or abnormal wear. This requires the use of specialised measuring tools for accurate measurement.

6. Relative rotation check of inner ring and outer ring:

Check whether the inner ring and outer ring of the separation bearing rotate flexibly relative to each other. If the rotation is not flexible or there is a phenomenon of jamming, it may be an indication of bearing wear or damage.

Tools that must be used when replacing the hydraulic release bearing:

1. spanner: for disassembling and tightening the bearing bolts.

2. screwdriver: for removing screws that may be present.

3. hydraulic pump or compressor: used to pressurise the clutch hydraulic system to aid the removal and installation of the release bearing.

4. specialised tools: some release bearings may require specialised dismantling tools such as a bearing remover or bearing compressor.

5. Cleaning tools: such as cloths, brushes, etc., are used to clean the bearing and housing of dust and dirt.

6. grease or lubricant: for applying new bearings.

7. safety stand or jack: for supporting the vehicle to ensure safety.

8. hydraulic hose fitting: may be required if the hydraulic hose needs to be replaced.

Please note that when replacing the hydraulic release bearing, make sure you use the proper tools and correct handling methods to avoid damaging the part or creating a safety risk. If you are not familiar with the repair operation, it is recommended to have it done by a professional automotive service technician.