Daewoo Nexia

since 1994 of release

Repair and car operation

Deu Neksiya
+ Maintenance instruction
+ Maintenance
+ Engine
+ 3. Engine (two top camshafts)
+ cooling System
+ Toplevnaya and exhaust systems
+ Electric chain
+ 7. Ignition system
+ 8. Electronic control unit and sensors
+ Transmission
+ 10. Five-speed transmission and main RPO MM5 broadcast
+ 11. Automatic Transmission
+ Steering
+ Running gear
+ 14. Forward suspension bracket
+ 15. Drive of forward wheels
+ 16. Back suspension bracket
- Brake system
   17.2. General description
   17.3. Check of a technical condition of brake system
   17.4. Filling of a tank of the main brake cylinder
   17.5. Air removal from brake system
   17.6. Washing of brake system
   17.7. Check of a regulator of brake forces
   17.8. Brake hoses (forward)
   17.9. Brake hoses (back)
   + 17.10. Parking brake
   17.11. Check of a condition of forward brake slips
   17.12. Check of a condition of back brake slips
   17.13. Brake disks
   17.14. Brake drums
   17.15. Brake pedal
   17.16. Main brake cylinder
   17.17. Tank
   17.18. Regulators of brake forces (proportional valves)
   17.19. Main brake cylinder assembled
   17.20. Repair of the main brake cylinder
   17.21. Disk brake mechanism
   17.22. Blocks and slips
   17.23. Protective cover of the piston
   17.24. Brake disk
   17.25. Support
   17.26. Guard
   17.27. Support repair
   17.28. Drum-type brake mechanism
   17.29. Adjustment of the brake mechanism
   17.30. Adjustment of the parking brake
   17.31. Basic brake disk
   17.32. Wheel cylinder
   17.33. Repair of the wheel cylinder
   17.34. Vacuum amplifier of brakes
   + 17.35. Anti-blocking system of brakes
   17.36. Air removal from a brake hydraulic drive
   17.37. Air removal from a brake hydraulic drive manually
   17.38. The valve for air removal from the block of modulators
   17.39. Electromagnetic valves of modulators
   17.40. The block of hydraulic modulators with electric motors
   17.41. Electronic control unit braking
   17.42. Sensor of angular speed of a forward wheel
   17.43. Flexible conducting of DUS of a forward wheel
   17.44. Sensor of angular speed of a back wheel
   + 17.45. Flexible conducting of DUS of a back wheel
   17.46. System electric safety lock
   17.47. ABS relay
   17.48. Signaling devices
+ Body
+ Heating, ventilation
+ Electric equipment


17.3. Check of a technical condition of brake system


Brake system check on dry, pure and rather equal platform with a good covering. Reliable check of a condition of brake system on damp or covered with dirt (including dry sand) a platform will be complicated because of various coupling of tires with a covering. The rough covering also is not suitable for check of brake system because of strong vertical fluctuations of wheels. The brake system should be checked at various intensity of braking and various speeds of the car. In all cases it is necessary to avoid blocking and sliding of wheels. Blocking of wheels does not speak about effective braking as the brake way thus turns out more in comparison with braking on a coupling limit when the braked wheels continue to rotate. This results from the fact that blocking of a wheel is accompanied by falling of coupling of the tire with a road surfacing. The brake system of the car is designed so that to reduce probability of blocking of wheels in most cases, most often meeting in usual operation, except for perhaps enough rare emergency braking with extremely big delay. Car braking without blocking of wheels not only reduces a brake way, but also provides preservation of stability and controllability of the car.

At big delays the brake pedal becomes more "rigid".

The external factors influencing work of brake system:

1) Tires. The tires having various contact and coupling with darling will brake differently. It is necessary to support identical pressure of air in tires. The tires located on one axis, should have approximately identical depth of drawing of a protector.

2) Car loading. At non-uniform loading of the car those wheels of which the big share of loading is the share, demand also the bigger brake moment, than the others. Higher efforts are necessary for braking of completely loaded car on a brake pedal.

3) Corners of installation of wheels. Violation of the correct corners of installation of wheels, especially distributed also a longitudinal inclination of an axis of turn, leads when braking to car withdrawal aside.

The brake system is equipped with a signaling device of malfunction of BRAKE which is located on a control panel. At ignition key turn in the situation START the signaling device of BRAKE should light up. After return of a key to the situation RUN the signaling device is switched off. The signaling device of BRAKE joins in the following cases:

– at turning on of the parking brake (ignition is included);
– when falling level of brake liquid in a tank of the main brake cylinder.

At the idling engine and a neutral in a transmission to press and hold a brake pedal with constant effort. If the brake pedal slowly falls, the possible reason of it are leakages of brake liquid. It is necessary to examine all brake system on existence of thinnesses. To check level of brake liquid in a tank. Small decrease in level of liquid can be caused by normal wear of brake shoes. Strong falling of level can testify to existence of leakages of liquid. In a brake hydraulic actuator are possible both internal, and external leakages of liquid. If level of brake liquid normal, it is necessary to check length of a pusher of the vacuum amplifier. If the length of a pusher differs from norm, it is necessary to adjust or replace a pusher. To check adjustment of working brake system and the parking brake.

Mentioned below checks of the main brake cylinder do not guarantee detection of all possible malfunctions of knot.

1) To check existence of cracks of the case of the cylinder and traces of brake liquid on an external surface of the cylinder. Falling of drops of brake liquid testifies to leaks. Cylinder moistening outside is admissible.

2) To check existence of jammings in a drive of a pedal and length of a pusher. If malfunctions it is not revealed, to dismantle and disassemble the cylinder. To check a condition of consolidations of the cylinder and pistons. If consolidations inflated or were extended, the possible reason of it is the brake liquid improper or polluted by extraneous substances. In this case bypass мо completely to disassemble the cylinder and to wash out all details. Rubber details are subject to obligatory replacement. It is necessary to wash out all hydraulic actuator of brake system also.

Application of unrecommended brands of brake liquids, and also hit in a hydraulic actuator of mineral oil or water leads to decrease in temperature of boiling of working liquid and failure of rubber consolidations.

Swelling of external sealing covers on the main thing or wheel brake cylinders testifies to failure of internal rubber consolidations.

At detection of signs of swelling of rubber details it is necessary to disassemble and completely to wash out all hydraulic actuator alcohol. Before assembly it is necessary to dry up a stream of the compressed air all details of a hydraulic actuator for a hit exception in brake system of alcohol. Rubber details, including brake hoses, are subject to replacement. It is necessary to check also existence of traces of brake liquid on brake slips. At strong pollution of slips it is necessary to replace them. If consolidations of the main brake cylinder as it should be, the possible reason the overheat of brake liquid is. In the absence of an overheat it is necessary to merge brake liquid, to wash out system fresh brake liquid, to fill in new brake liquid and to remove air from a hydraulic actuator.