The clutch release bearing
is subjected to axial load, impact load, and radial centrifugal force during high-speed rotation during use. In addition, since the fork thrust and the reaction force of the separating lever are not on the same straight line, a torsional moment is also formed. Clutch release bearing has poor operating conditions. It intermittently rotates at high speed and withstands high-speed friction. It has a high temperature, poor lubrication conditions, and no cooling conditions.
The damage of the clutch release bearing has a lot to do with the driver's operation, maintenance and adjustment. The reasons for the damage are roughly the following:
Excessive operating temperature causes overheating
Many drivers often step on the clutch when turning or slowing down. Some drivers also put their feet on the clutch pedal after the gear is engaged. This can result in incomplete clutch separation and the clutch is in a semi-engaged and semi-detached state. This state causes dry friction and generates a large amount of heat transfer to the separation bearing. The bearing is heated to a certain temperature, and the butter melts or dilutes the flow, so that the temperature of the separation bearing is further increased. When the temperature reaches a certain level, it burns out.
Lack of lubricant and wear
The clutch release bearing is lubricated with butter. There are two ways to add butter. One is to open the rear cover of the bearing to fill the grease during maintenance or when removing the transmission, and then reassemble the back cover. The other is to remove it and put it in the melted grease for digesting, and then take it out after cooling to achieve the purpose of lubrication. The amount of wear of the separated bearing in the case of no lubrication or less lubrication is often several of times to several tens of times the amount of wear after lubrication. The increased wear of the release bearing is more likely to be damaged.
Free travel is too small or too many loads
According to requirements, the gap between the general clutch release bearing and the separating lever is 2.5 mm. It is reflected in the free travel of the clutch pedal is 30mm-40mm. If the free travel is too small or there is no free travel at all, the separation lever and the release bearing will be in a normally engaged state. According to the fatigue failure principle, the bearing working time is longer, and the damage is more serious. Moreover, the working time is longer, and the temperature of the bearing is higher and it is easier to burn.
In addition to the above three reasons, whether the separation lever is adjusted flat or not, and whether the separation bearing return spring is good or not, has a great influence on the damage of the separation bearing.