All articles about the device and repair of units and elements of the brake system of VAZ-2121 Niva cars and their modifications.
Brake system diagram The diagram of the brake system is shown in fig. 6-1. Pic. 6-1. Brake system diagram: 1 - front brake cylinder block; 2 - a reservoir of a hydraulic drive of brakes; 3 - main...
Checking the performance of the vacuum booster Press the brake pedal 5-6 times with the engine off to create in cavities A and E (pic. 6-2) the same pressure, close to atmospheric pressure. At the same time, by the force...
Adjustment of a drive of brakes The free travel of the brake pedal with the engine off should be 3-5 mm. This value is obtained by adjusting the position of the switch 6 (pic. 6-3) stop signal. Pic. 6-3. Brake...
Parking brake adjustment If the parking brake does not hold the vehicle on a slope of up to 30°or is activated when the lever is moved more than 4-5 teeth of the ratchet, adjust it in the following order:...
Checking the performance of the pressure regulator Place the vehicle on a lift or inspection ditch, clean the pressure regulator and protective cover from dirt. Carefully remove the protective cover from the pressure regulator,...
Adjustment of a backlash between pads and a drum The adjustment procedure is as follows: press the brake pedal with a force of 98-117.5 N (10-12 kgf), to ensure the fit of the pads to the drum; holding the pads in this position,...
Adjusting the position of the pressure regulator If the bolts securing the pressure regulator are loosened, then adjust its position by first hanging the rear axle of the car. Then disconnect lever 4 (pic. 6-6) from rod 8 and...
Removal of air from the hydraulic actuator The air that got into the brake hydraulic drive when replacing pipelines, hoses, sealing rings or when the system is leaking causes an increase in the free play of the brake...
Clutch and brake pedal bracket Removal and installation To remove the pedal bracket: remove the steering shaft bracket as directed in section «Steering»; Disconnect the pusher of the vacuum booster from the...
Vacuum booster — removal and installation When removing the booster, the main cylinder of the hydraulic brake drive is not disconnected from the hydraulic system so that air does not enter it. Withdrawal procedure....
Brake master cylinder device The device of the main cylinder of a drive of brakes is shown in fig. 6-10. Pic. 6-10. Hydraulic brake master cylinder: 1 - cork; 2 - cylinder body; 3 - front brake drive piston;...
Master cylinder — removal and installation Disconnect the flexible hoses from the master cylinder and cover the hoses and fittings on the cylinder to prevent leakage of fluid from the reservoir and entry of dust, dirt or...
Master cylinder — disassembly and assembly Remove fittings 3 (pic. 6-11) with sealing washers 4. remove the cap 5, unscrew the locking bolts 7 and remove all parts in the order shown in fig. 6-11. Pic. 6-11. Brake Master...
Master Cylinder — Parts Check Before assembly, wash all parts with isopropyl alcohol; dry them with compressed air or wipe them with a clean cloth, avoiding contact with mineral oil, kerosene or diesel fuel,...
Master Cylinder Leak Test Install the master cylinder on the stand and connect it to the elements of the stand, as shown in fig. 6-12. Pic. 6-12. Main cylinder leak test diagram: 1 - valve for pumping the...
Front brake device The front brake device is shown in fig. 6-13. Pic. 6-13. Front wheel brake: 1 - cylinder block; 2 - brake pads; 3 - clamping lever of the caliper; 4 - protective cover; 5 - axis...
Front brakes — removal and installation Removing Raise the front of the car, put it on stands and remove the wheel. Remove the hose guide brackets. Turn away bypass bolts, disconnect from the block of cylinders hoses 10...
Front brakes — disassembly and assembly Remove cotter pins, then axle 5 ( rice. 6-13 ), while holding the clamping levers 3 so that the springs do not pop out. Remove the pressure levers and their springs, and then the...
Front brakes — checking details Carefully check all parts by first washing them with warm water and detergent and drying them with a jet of compressed air. If signs of wear or seizure are found on the pistons...
Front brakes — check brake disc runout Check the axial play of the brake disc without removing it from the vehicle (pic. 6-16). The largest allowable runout on the indicator is 0.15 mm; if the runout is greater, then...
Front brakes — replacing brake pads The pads are replaced with new ones if the thickness of the pads has decreased to 1.5 mm. To replace pads, do the following: unpin the axle of the upper clamping lever, remove it...
Rear brake device The rear brake device is shown in fig. 6-18. Pic. 6-18. Rear wheel brake: 1 - wheel cylinder; 2 - lever for manual drive of the pads; 3 - brake block; 4 - a cup and a support rack...
Rear brakes — removal and disassembly Raise the rear of the car and remove the wheel. Take measures to prevent leakage of fluid from the tank. Puller 67.7823.9519 (pic. 6-19) remove the brake drum. Pic. 6-19. Removing...
Rear brakes — assembly and installation Install the wheel cylinder on the brake shield and attach the brake fluid supply pipe to it, tighten the fitting nut to failure Attach lever 2 to the block ( see fig. 6-18 ) the...
Rear brakes — checking details Wheel cylinders Disassemble the wheel cylinders, for which remove the protective caps 1 (pic. 6-20) and pistons 2, remove seals 3, support cups 5 and spring 7. Then unscrew...
Rear brake pressure regulator — removal and installation Disconnect lever 12 (pic. 6-22) from the rod 7, and then the clip 18 from the bracket 14 and the bracket for fastening the pipelines going to the pressure regulator. Pic. 6-22....
Rear brake pressure regulator — disassembly and assembly Using the key A.56124, unscrew the plug, remove the gasket 5 (pic. 6-23) remove piston 10, spacer sleeve 2, seal 7, plate 8, spring 9 and thrust washer with sealing ring 3. Pic....
Parking brake — removal and installation With the parking brake lever in its lowest position, disconnect the ends of the cables from the brake shoe levers (see « Rear brakes »). Loosen locknut 5 ( rice. 6-4 ) and...
Parking brake — check and repair Carefully check the condition of the parking brake parts. If a break or rubbing of the wires is detected, replace the cable with a new one. Make sure that the sector teeth and...