Clutch release bearing, also known as clutch throwout bearing, is a key component in automobiles and other power transmission equipment, located between the clutch and transmission. Its main functions and roles are listed below:

Clutch release bearing definition and location

Definition: Clutch release bearing is a kind of thrust bearing, which is used to transmit thrust in the clutch system to ensure the smooth separation and combination of the clutch.

Position: It is located between the clutch and the transmission, connecting the clutch pressure plate and fork and other components.

Clutch release bearing main function

1. Eliminate friction: When the clutch pedal is pressed down, the clutch release bearing can eliminate the direct friction between the high-speed rotating clutch pressure plate and fork, thus protecting these parts from wear and tear.

2. Separate power: By pushing the pressure plate and the friction plate to separate, the clutch release bearing interrupts the power transmission from the crankshaft to the transmission, and realises the smooth cut-off of power.

3. Smooth binding: When the clutch pedal is released, the release bearing's reset action helps the clutch bind smoothly, ensuring the continuity and smoothness of power transmission.

How to test a throw out bearing?

Testing a throw out bearing (i.e. clutch release bearing) is a process that involves expertise and tools. Below is a consolidated test procedure that avoids duplication and maintains the integrity and accuracy of the information:

Test Clutch Release Bearing Process

1. Preparation

Determine the test environment: Test in a safe, dust-free environment.

Prepare tools: micrometers, vernier calipers, vibration measurements, microphones, thermal sensors, special mounting fixtures and bearing supports, etc.

Cleaning bearings: Thoroughly clean the bearings to remove oil and impurities.

2. Dimension and appearance inspection

Measuring dimensions: Use micrometer or vernier calipers to measure the inner diameter, outer diameter and width of the bearings.

Checking appearance: Observe whether there are defects such as cracks, corrosion, indentation or spalling on the bearing surface.

3. Rotational accuracy test

Mounting the bearing: Mount the bearing on the special test fixture or bearing bracket.

Rotation test: rotate the bearings slowly manually or by using electric tools, observe whether the rotation is smooth and whether there is any stagnation or abnormal noise.

4. Functional test (on the car)

Start the engine: Place the vehicle in a safe position, start the engine and idle it.

Depress the clutch pedal: slowly depress the clutch pedal, noting any abnormal noises.

Releasing the clutch pedal: slowly release the clutch pedal, again noting the noise and feel.

Clutch Disengagement Test: Check that the clutch can be fully disengaged.

Shift test: Try to shift gears while the vehicle is running and check for smoothness.

5. Vibration and noise test

Vibration measurement: Use a vibration meter to measure the vibration of a rotating bearing.

Noise check: Use a stethoscope to check the rolling sound of the bearings, noting abnormal or irregular sounds.

6. Temperature testing

Temperature monitoring: After the bearing has been rotating for a period of time, use a heat sensor to monitor the working temperature of the bearing.

7. Specialised tool inspection (optional)

Use specialised tools: e.g. manometer to check pressure in the clutch system.

Clearance measurement: Use calipers or micrometers to measure the clearance of the bearing.

8. Data analysis and judgement

Comprehensive analysis: Judge the quality condition of the bearing based on all test results.

Decision-making: If abnormalities or non-compliance with specifications are found, they should be replaced or repaired in a timely manner.

Precautions

Safe operation: Strictly observe the safety operation regulations to prevent accidents.

Equipment and tools: Ensure that the test equipment and tools are in good performance and meet the standards.

Technical manuals: Refer to relevant technical manuals and standards for operation.

Professionals: If you are unsure how to conduct the test or inspection, it is recommended that it be done by a professional automotive service technician.

Through these steps, the condition of the throwout bearing can be fully and accurately assessed and a decision made as to whether further repair or replacement action is required.