Recently, many car owners have reflected that when replacing the brake pads and brake discs, when the old pieces of the old discs were removed, some brake discs will have some scratches and chromatic aberrations, and serious cracks will occur. I have a lot of common questions about the brake pads and brake discs, and share them with the owners:
First, what is the cause of the friction between the brake disc and the sheet?
1, the brake pad material has a hard point, caused by friction at high temperatures.
2, when the brake disc is cast, the surface heat treatment defects, resulting in uneven surface hardness, scratches caused by the harder place.
Second, what is the reason for a vertical grain on the brake disc?
Reason: This is caused by the brake disc exceeding the limit. It is usually caused by long-distance or multi-frequency long-distance brakes. If you do not change at this time, it may cause a crack.
3. The reason for the crack deformation of the hub contact surface around the mounting hole of the brake disc.
Cause: The brake disc tightening sequence is incorrect, and the tightening torque of the screw is insufficient.
Impact: Steering wheel shakes when braking begins.
Solution: Replace the brake discs and tighten in the correct order and tightening torque
Fourth, blue or dark spots appear in some areas of the brake disc
Cause: The hub is beating too much. The uneven contact between the brake disc and the brake pad caused excessive sway, resulting in localized heat and then fading (blue).
Impact: Noise and vibration gradually increase.
Solution: Correct the wheel bounce and ensure that the hub is bouncing within the correct tolerances.
5. The brake disc is severely worn and has grooves on its surface.
Cause: The brake pads are excessive or completely worn, causing the brake pad to come into contact with the brake disc (metal to metal), thereby damaging the brake disc surface.
Impact: Braking efficiency is greatly reduced, and braking distance and harsh noise are increased.
Solution: Please replace the brake disc and brake pad. In case of use, please confirm whether the brake pad wear alarm indicator circuit works normally.
Sixth, a deep groove is formed between the small end of the brake disc and the surface of the brake disc
Cause: Excessive wear of the brake pads and brake discs may cause the backing plate to move within the brake caliper. If this is the case, then the back plate of the worn brake pad has been released from its base (located inside the brake caliper) Thus, a groove is formed between the small end of the brake disc and the surface of the brake disc.
Effect: The braking efficiency is very low, the brake pedal stroke is also long, and accompanied by strong noise.
Solution: Please replace the brake disc and brake pad; check the brake caliper, if necessary, repair the brake caliper.
Seven, the brake disc surface shows different brightness and chromaticity
Cause: The brake disc is not ground. This phenomenon usually occurs on the new brake. The surface between the brake pads of the new brake and the brake disc will be slightly offset. If the new brake is not worn, the friction surface will overheat. , resulting in metallurgical changes in the friction surface.
Effect: Due to the reduced friction, the braking efficiency is reduced. In addition, vibration is generated, and the vibration is more severe with the use of brake pads and brake discs.
Solution: Replace the brake disc and run the brakes in accordance with the correct running-in procedure, ie use the brakes moderately during the first 200 km of the vehicle.
Eight, the brakes are abnormal, the deviation is biased, the braking force is insufficient, the brake pedal is soft, and the brakes are abnormally worn.
1. The normal wear of the brake pads remains in the vicinity of the brake cylinder. If it is not cleaned for a long time, it will cause abnormal noise.
2. When driving on gravel road, some particles will splash between the sheet and the disc, causing abnormal noise or abnormal wear.
3. The silencer and shock absorbing sheet of the brake pad are not cleaned and lubricated for a long time, which will cause abnormal noise.
4. The pump guide pin is rusted, the brake pads are not returned, the inner and outer brake pads are unevenly worn, the braking force is reduced, and the brakes are biased.
5, the brake disc wears a serious groove, the braking distance is extended and the car can not be stopped.
Nine, new brake pad running-in cycle
Under normal circumstances, the new film needs to run for 500 kilometers, and the old film needs to run for 2,000 kilometers.
