Cause | Elimination Method |
Insufficient braking performance | |
Leakage of brake fluid from the wheel cylinders of the front or rear brakes | Replace bad parts of wheel cylinders, wash and dry pads and drums, bleed the hydraulic drive system |
Air in the brake system | Remove air from the system |
Damaged rubber seals in the master cylinder | Replace seals and bleed system |
Damaged rubber hoses of the hydraulic drive system | Replace hoses |
Spontaneous braking when the engine is running | |
Air leakage in the vacuum booster between the valve body and the protective cap: | |
- destruction, distortion of the cover seal or poor fixation due to damage to the locking parts, wear of the seal | - replace the vacuum booster |
– insufficient lubrication of the cover seal | - remove the protective cap and put grease into the seal |
Incomplete release of all wheels | |
There is no free play of the brake pedal due to the incorrect position of the brake light switch | Adjust switch position |
The protrusion of the adjusting bolt of the vacuum booster relative to the mounting plane of the master cylinder is broken | Adjust protrusion (1.25 - 0.2 mm) adjusting bolt |
Jamming of the valve body of the vacuum booster due to swelling of the diaphragm or pinching of the seal of the booster cover or protective cap | Replace vacuum booster |
Clogged compensation hole in the master cylinder | Clean the hole and bleed the hydraulic drive system |
Swelling of the rubber seals of the main cylinder due to the ingress of gasoline, mineral oils, etc. into the liquid. | Thoroughly flush and bleed the system with brake fluid, replace damaged rubber parts, bleed the hydraulic drive system |
Brake Master Cylinder Piston Seizure | Check and, if necessary, replace the master cylinder, bleed the system |
Braking of one of the wheels with the brake pedal released | |
Weak or broken rear brake shoe return spring | Replace spring |
Seizure of the piston in the wheel cylinder due to corrosion | Dismantle the cylinder, clean and wash the parts, replace the damaged |
Swelling of the sealing rings of the wheel cylinder due to the ingress of fuels and lubricants into the liquid | Replace the rings, flush the hydraulic drive system with brake fluid |
No gap between pads and drum | Adjust parking brake |
Violation of the position of the caliper relative to the brake disc when the bolts of fastening to the bracket are loosened | Tighten the mounting bolts, if necessary, replace damaged parts |
Increased brake disc runout (more than 0.15 mm) | Grind the disc, if the thickness is less than 9mm, replace the disc |
Winding up or pulling the car to the side when braking | |
Leakage of brake fluid in one of the wheel cylinders | Replace seals and bleed system |
Jamming of the piston of the wheel cylinder of brakes | Check and eliminate the jamming of the piston in the cylinder, if necessary, replace the damaged parts |
Blockage of any steel pipe due to a dent or blockage | Replace the tube or clean it and bleed the system |
Different tire pressure | Adjust the pressure |
Incorrect wheel alignment | Adjust wheel alignment |
Dirty or oily discs, drums and linings | Clean the brake parts |
Incorrect pressure regulator setting | Adjust its position |
Defective pressure regulator | Repair it or replace it |
Increased brake pedal pressure | |
Vacuum booster air filter clogged | Replace air filter |
Jamming of the valve body of the vacuum booster due to swelling of the diaphragm or pinching of the seal of the booster cover or protective cap | Replace vacuum booster |
The hose connecting the engine vacuum pipe is damaged or its fastening on the fittings is loose | Replace hose or tighten hose clamps |
Swelling of cylinder seals due to the ingress of gasoline, mineral oils, etc. into the liquid. | Thoroughly flush the entire system, replace damaged rubber parts; bleed the system |
Screeching or screeching brakes | |
Weakening of the return spring of the rear brake pads | Check return spring and replace if necessary |
Out-of-roundness of rear brake drums | Waste the drums |
Lubrication of friction linings | Scrub the pads with a wire brush using warm water and detergent. Eliminate the cause of fluid or grease on the brake pads |
Wear of linings or the inclusion of foreign bodies in them | Replace pads |
Excessive brake disc runout or uneven wear | Grind the disc, if the thickness is less than 9 mm, replace the disc |