What is a Throw-out Bearing?

Throw-out bearing, also known as thrust bearing or clutch release bearing, is an important part of the automotive clutch system. Its main function is to push the clutch pressure plate to separate the clutch disc from the flywheel when the clutch is disengaged, thus cutting off the power transmission between the engine and the gearbox.

The throwout bearing is usually located inside the clutch housing and is connected to the clutch pedal through a series of levers, springs and bearings. When the driver depresses the clutch pedal, the throwout bearing is moved forward by a series of mechanical transmissions, pushing the clutch pressure plate to compress the spring on the clutch disc, which separates the clutch disc from the flywheel. As a result, the engine power is no longer transmitted to the gearbox, thus enabling operations such as shifting gears or stopping.

The throwout bearing is one of the parts of the clutch system that is subjected to high loads and wear and tear, so it needs to be inspected and replaced periodically to ensure that the clutch system works properly.

How to Repair Throw-out Bearing (release bearing)

Repairing a throw-out bearing (also known as a thrust bearing or clutch release bearing) usually requires some mechanical knowledge and expertise. The following are general repair procedures, but please note that the exact steps may vary depending on the vehicle model and bearing type:

1. Disassemble the throwout bearing:

First, the clutch system needs to be disassembled to expose the throwout bearing. This usually involves removing components such as the clutch pressure plate, clutch disc and flywheel.

Carefully mark and record the location of all parts and connections made during disassembly so that they will be correct when reassembled.

2. Inspection and Cleaning:

After disassembling the bearing, carefully inspect its appearance for wear, cracks or damage.

Clean the bearing and its surrounding parts with a suitable cleaning agent (e.g. paraffin or specialised bearing cleaner) to ensure that all dirt and old lubricants are removed.

3. Replace or repair the throwout bearing:

If the bearing is so badly damaged that it cannot be repaired, it will need to be replaced with a new one.

If the bearing is only slightly worn or damaged and is in a repairable condition, repair may be attempted (but please note that such repair is usually only available for specific types of bearings and may require special tools and techniques).

4. Reassembly:

Before installing a new or repaired bearing, make sure that all relevant parts have been cleaned and are in good condition.

Reassemble the clutch system in the reverse order of disassembly, taking care to ensure that all parts are correctly fitted and tightened in place.

5. Testing and adjustment:

After assembly is complete, start the engine and test the operation of the clutch system. Check to see if the clutch pedal is smooth, if the clutch is slipping or rattling, etc.

Make any necessary adjustments as needed to ensure that the clutch system is working properly.

Repairing a throwout bearing (also known as a thrust bearing or clutch release bearing) requires a range of specialist tools, equipment and skills. Below are some of the tools and skills that may be required during the repair process:

Tools required to repair a throwout bearing

1. Disassembly tools:

Screwdrivers and spanners: for removing clutch system housing, fixing bolts, etc.

Puller (Llama): specifically for dismantling bearings and fasteners that are difficult to remove manually.

Specific Clutch Removal Tool: Some models may require a specific clutch removal tool to easily remove the clutch pressure plate and bearing.

2. Cleaning tools:

Cleaning solvent (e.g. paraffin, petrol or special bearing cleaner): used to clean dirt and old lubricant from bearings and clutch system components.

Cleaning containers and brushes: for holding cleaning solvents and cleaning parts.

3. Measuring tools:

Vernier calipers, micrometers: used to measure the dimensions of bearings and other parts to ensure the fit of new parts.

Depth Ruler: Used to measure the depth of bearing housings and other mounting locations.

4. Mounting tools:

Press fitting machine or special fitting tool: used to fit the new bearing correctly into the clutch system.

Torque spanner: for tightening bolts to ensure that the torque values specified by the manufacturer are met.

Skills required to repair a throwout bearing

1. Mechanical knowledge:

Familiar with the structure and working principle of the clutch system and understand the relationship and interaction between the components.

Be able to recognise and diagnose the cause and extent of bearing damage.

2.Disassembly and assembly skills:

Knowledge of the correct sequence of disassembly and assembly to avoid damaging other components or affecting the performance of the clutch system.

Be able to use proper tools and techniques to disassemble and install bearings.

3. Cleaning and inspection skills:

Ability to thoroughly clean bearings and clutch system components to remove all dirt and old lubricants.

Use measuring tools to check dimensions and wear of bearings and other components to determine if replacement is necessary.

4. Troubleshooting and diagnosis:

Be able to determine the cause of bearing damage based on vehicle symptoms and inspection results, and formulate appropriate repair plans.

Be able to detect and solve potential problems in time during the repair process to ensure that the clutch system can work properly.

5.Safety awareness:

When carrying out repair work, always follow safe operating procedures and wear appropriate personal protective equipment.

Pay attention to fire and explosion prevention, ensure that the work area is well ventilated, and avoid the use of flammable and explosive cleaning solvents.

NOTE: As the replacement of throw-out bearings involves complex mechanical operations, it is usually recommended that it be carried out by a professional mechanic, especially for vehicle owners who do not have a lot of experience in automotive repairs, as the process may be too complicated and time-consuming.

The cost of a throwout bearing replacement includes not only the cost of the part, but also the cost of labour hours, which can vary depending on the region, model and repair location. If not repaired in a timely manner, a damaged throwout bearing can lead to damage to other clutch components, increasing subsequent repair costs.