The brake pedal travel is too large, the braking effect is slow, the braking efficiency is very low or even lost, and the braking distance increases.
Cause of failure:
1. Insufficient brake oil pressure. (The brake master cylinder lacks oil, the brake pipe is broken, the oil pipe joint is leaking, and the oil circuit is blocked);
2. There is air in the braking system;
3. The free travel of the moving pedal or the brake clearance is too extensive, the brake shoe friction plate is in poor contact, and the wear is severe or oily; The bowl is aged and damaged.
Troubleshooting:
1. Depress the brake pedal continuously; for example, the pedal gradually rises and has a springy feeling but stops after a while. When the pedal is still low, there is air in the brake system, and the brake system should be exhausted at this time.
2. The braking with one foot does not work, but the braking effect is perfect when the pedal is stepped on several times in a row. Generally, the free travel of the brake pedal is too extensive, or the braking gap is too large. The pedal free travel should be adjusted, the brake clearance should be checked, and if necessary, the brake should be disassembled and repaired.
3. When the brake pedal is stepped on, it is neither weak nor heavy, but the braking effect is not good. This phenomenon is a wheel brake failure, such as oil or poor contact of the brake shoes and aging of the friction pads. , wear uneven wear of brake drum. The technical condition of the brakes should be checked, adjusted, and repaired if necessary.