What is a clutch release bearing

The clutch release bearing, also known as the Clutch Throwout Bearing, is a key component in the automotive transmission system, located between the clutch and the transmission. Its main function is to push the release lever or fork through a series of mechanical linkages when the driver operates the clutch pedal, thus separating the clutch pressure plate from the clutch friction disc. This process allows the engine speed to be disconnected from the transmission, enabling the driver to shift gears without interrupting power transmission. 

Release bearings are designed to withstand the centrifugal forces associated with high speed rotation as well as the axial forces during clutch release. To increase durability and reduce wear, modern release bearings may feature angular contact ball bearings and may be designed with a fully sealed construction, high-temperature grease, and in some cases self-aligning features to accommodate different centrifugal conditions, reduce wear and noise, and extend service life. When not in operation, the release bearing maintains a certain clearance with the release lever by means of a return spring to avoid premature wear caused by continuous contact. Its good working condition is essential to ensure smooth engagement and disengagement of the clutch as well as the smooth operation of the entire transmission system.

Where does the clutch release bearing go?

The clutch release bearing is normally fitted to the gearbox fork and is located on the back of the clutch disc. To locate the release bearing, which is usually found under the vehicle's hood or transmission cover, it is mounted on the forks and is located inside the flywheel housing where it connects to the forks.

Specifically, the clutch release bearing seat is loosely fitted to the tubular extension of the transmission's first shaft bearing cover, and the convex shoulder of the release bearing is kept against the release fork at all times by means of a return spring, and backed into its final position, with a clearance of about 3 to 4 mm from the end of the release lever (release finger).

When the driver depresses the clutch pedal, the release bearing pushes the release lever (or release fork), which in turn separates the pressure plate from the slave plate, thus interrupting the power transfer from the engine to the gearbox and permitting the gearshift operation. This component, when not in operation, maintains a certain amount of clearance from the release lever by means of a return spring to minimise unnecessary wear. The clutch release bearing is therefore a key component in the clutch system and its proper functioning is vital to the operation of the vehicle.

If the clutch release bearing is damaged, it may cause the clutch to fail to work properly, thus affecting the driving safety of the vehicle. Therefore, once the clutch release bearing is found to be faulty, it should be inspected and repaired or replaced in a timely manner. Repairing or replacing the clutch release bearing requires specialised skills and tools, so it is recommended to seek the help of a professional repairer.