What is a clutch release bearing?

A clutch release bearing, also known as a clutch release bearing or throwout bearing, is a critical component in a manual transmission vehicle. It is located between the clutch pedal and the transmission, and its main function is to help disengage the clutch pressure plate from the flywheel when the driver depresses the clutch pedal, thus severing the connection between the engine and the drivetrain. This process allows the driver to shift gears without interrupting the flow of power, ensuring smooth acceleration or deceleration of the vehicle.

Clutch release bearing working principle:

1. Engaged state: When the clutch is engaged, the engine power is transferred to the clutch pressure plate through the flywheel and then to the transmission, which drives the wheels.

2. Separation action: when the driver depresses the clutch pedal, the separation bearing is pushed forward through the mechanical linkage or hydraulic system, which makes the separation bearing act on the central part of the clutch pressure plate, forcing the pressure plate to retreat, breaking contact with the flywheel, and realising the temporary disconnection of power.

3. Reset: When the driver releases the clutch pedal, the spring action causes the pressure plate to return to its original position, re-contacting the flywheel and resuming power transmission.

What causes a clutch bearing to fail?

Clutch release bearing failure causes and preventive measures

 I. Reasons of clutch release bearing failure

 1. Improper driving habits and maintenance

- Bad driving habits:

  - Frequent semi-linkage operation: Continuously depressing the clutch pedal when turning or decelerating causes the release bearing to be in working condition for a long time, resulting in overheating and wear.

  - Failure to release the clutch pedal in time after shifting gears: causes the release bearing to work for a long time, increasing wear.  

- Insufficient maintenance:

  - Lack of lubrication: the clutch release bearing needs regular lubrication, if there is a lack of lubrication or insufficient lubrication, it will lead to increased wear of the bearing.

  - Neglect of regular inspection and maintenance: Failure to detect and replace worn bearings in time leads to worsening of the problem.

 2. Improper installation and adjustment

- Incorrect mounting position:

  - Deviation from the design requirements: Incorrect mounting position will lead to uneven force and accelerate wear.  

- Improper adjustment of free travel:

  - Freewheeling stroke too small: prolonged contact between release bearing and release lever leads to excessive wear.

  - Free travel too large: may lead to incomplete clutch separation, affecting the shift effect.

 3. Clutch release bearing quality problem

- Poor material:

  - Material defects: poor material is prone to self-loss in the process of use, shortening the service life.

  - Poor manufacturing process:

  - The size does not meet the requirements: poor manufacturing process may lead to bearing size does not meet the requirements, affecting the normal work.

 4. poor working conditions

- High temperature and friction:

  - Poor heat dissipation: the clutch release bearing needs to bear the heat generated by high speed rotation and friction in the working process, if the heat dissipation is poor or the temperature is too high, it will lead to bearing damage.

  - Poor lubrication conditions:

  - Lack of oil or poor lubrication: the working environment of the clutch release bearing is usually poor, poor lubrication conditions, it is easy to accelerate the wear due to lack of oil or poor lubrication.

 5. Other factors

- Abnormal wear of the release lever:

  - Uneven force or jamming: Abnormal wear of the release lever may lead to uneven force or jamming of the release shaft, accelerating the damage of the bearing.

  - Vehicle use conditions:

  - Driving environment: The driving environment, road conditions and driving habits of the vehicle will also have an impact on the life of the clutch release bearing.

  - Overload use:

  - Overloading or sudden overloading: overloading or sudden overloading of the vehicle may cause the bearing to be loaded beyond the design capacity instantly, thus fracture occurs.

 II. Preventive Measures

 1. Correct driving

- Avoid frequent half-linkage operation: Reduce unnecessary half-linkage state and avoid pressing the clutch pedal for a long time.

- Release the clutch pedal in time: Release the clutch pedal in time after shifting gears to reduce the wear of the bearing.

 2. Regular maintenance of the clutch release bearing

- Regular lubrication: Ensure the clutch release bearing is lubricated regularly to reduce friction and wear.

- Regular inspection: Check the wear and tear of the clutch system regularly and replace the worn parts in time.

 3. Correct installation and adjustment

- Ensure correct installation position: Install the clutch release bearing in strict accordance with the manufacturer's requirements to ensure accurate position.

- Adjust the free travel: Make sure the free travel of the clutch pedal is within the proper range, avoid too small or too large.

 4. Select high quality clutch release bearing

- Choose high quality materials: choose bearings with good materials and advanced manufacturing process to ensure their durability.

- Purchase from formal channels: Purchase bearings from formal channels to avoid using inferior products.

 5. Improve working conditions

- Keep clean: clean the clutch area regularly to prevent dirt and dust from entering the bearing.

- Avoid high temperature: Try to avoid using the clutch for a long time in a high temperature environment to ensure good heat dissipation conditions.

 Symptoms and judgement of clutch release bearing failure

 1. Symptoms of failure

- Strange noise: When depressing the clutch pedal, you may hear obvious ‘rustling’ or ‘squeaking’ sound.

- Change in pedal feel: The clutch pedal becomes unusually heavy, or there is unusual resistance during the pedal stroke.

- Difficulty in shifting gears: Shifting gears becomes rough, or there is even a clunking sound.

- Jittery start: The vehicle jerks when starting or is difficult to start smoothly.

- Decreased acceleration performance: In severe cases, vehicle acceleration will be affected.

 2. Judgement method

- Listen to the sound: When depressing the clutch pedal, pay attention to whether there is abnormal noise.

- Check the pedal feeling: note whether there is any change in the free travel of the clutch pedal and how it feels when it is operated.

- Observe the shifting situation: whether the shifting is smooth or difficult.

- Professional inspection: Go to a repair shop for inspection, the mechanic can confirm by test drive and dismantling inspection.

 Steps for replacing the clutch release bearing

 1. Prepare tools and materials

- Tools: jack, support frame, spanner, screwdriver, pliers, etc.

- Materials: new clutch release bearing and necessary lubricating oil.

 2. Remove related parts

- Remove auxiliary parts: Remove auxiliary parts such as battery, air filter and starter.

- Remove the tyre and swing arm: Remove the connecting screws of the tyre and swing arm, and remove the half shaft.

- Remove the gearbox: remove the circle of screws around the gearbox and engine and remove the legs.

 3. Removing the gearbox

- Remove the gearbox: remove the gearbox from the body to access the clutch system.

- REMOVE ORIGINAL PARTS: Remove the original clutch release bearing, pressure plate and clutch disc.

 4. Install the new clutch release bearing

- Clean the relevant parts: Clean the relevant parts of the clutch system to ensure that they are free from oil and impurities.

- Fixing the new parts: Fix the new clutch disc and pressure plate, using special tools to ensure alignment.

- Install new bearing: Install the new clutch release bearing and apply appropriate amount of lubricant as needed.

 5. Reassemble the gearbox and clutch system

- Reinstall Transmission: Reinstall the transmission to the vehicle and reverse the other installation steps in the disassembly procedure.

- CHECK AND TIGHTEN: Check and tighten all bolts and nuts to ensure solid connections.

 6. Check and test

- CONNECT BATTERY NEGATIVE POSITION: Connect the negative battery terminal and start the engine.

- Check Pedal Operation: Check the operation of the clutch pedal to ensure that the clutch can be disengaged and engaged smoothly.

- Test driving: Perform test driving to check the working performance of the clutch and the gear shift.

 V. Precautions

- Use matched bearings: Make sure to use bearings that match the vehicle model and specifications.

- Handle with care: Be careful during disassembly and assembly to avoid damaging other parts.

- Adequate testing: After the replacement is completed, carry out adequate testing to ensure that the clutch system works properly.

Through the above measures, the service life of the clutch release bearing can be effectively extended to ensure the normal operation of the clutch system.