NOTE: It is difficult to measure the thickness of a completely worn brake shoe lining with sufficient accuracy. Therefore, measure the overall thickness of the shoe and subtract the thickness of the shoe base (2.0 mm) from the obtained value.
Replace the pads in the following cases:
- the thickness of the friction linings is less than the permissible value;
- the surface of the linings is oily;
- the friction lining is not firmly connected to the base;
- the overlays have deep grooves and chips.
WARNING: Do not use gasoline, diesel fuel or any other mineral solvents to clean brakes.
WARNING: Replace the brake pads on both rear wheels at the same time.
You will need: a lug wrench, fine-nosed pliers, a flat-blade screwdriver, and sliding pliers with a lock.
1. Engage first gear and place chocks under the front wheels.
2. Check that the parking brake lever is lowered all the way down (the vehicle is released).
3. Remove the wheel (see "Changing a Wheel") and place the car on a support.
4. If the brake fluid level in the master cylinder reservoir is at or near the "MAX" mark, pump out some of the fluid from the reservoir. Otherwise, it may spill out when replacing the pads.
5. Remove the brake drum (see "Removing and installing the brake drum").
6. Turn up…
7. …and remove the clamps of both brake shoes by pulling them towards you.
WARNING: The brake caliper posts are difficult to access from the back of the shield. Therefore, make sure that the posts do not move deeper into the holes in the shield, and do not remove the posts unless absolutely necessary.
8. If you are removing worn brake pads to replace them with new ones, first set the clearance adjuster to its original position by pressing the spring stop of the adjuster ratchet mechanism upwards with a screwdriver…
9. ...and, holding the stop, tighten the regulator toothed nut with pliers until it stops, turning it clockwise.
10. Using a screwdriver, pry the bent end of the upper tension spring off the rear shoe with pliers, unhook its other end from the front shoe and remove the spring.
WARNING: Be careful when using pliers and a screwdriver. We recommend using special pliers for removing tension springs.
11. Move the rear shoe back a little and remove the spacer bar assembly with the clearance adjuster.
12. Move the brake shoes down, removing them from the lower stop on the brake shield, to relieve the tension of the lower return spring, remove the spring and the front shoe.
13. Move the rear cable extension end back into the release lever slot until it aligns with the slot in the lever…
14. …disconnect the cable end from the release lever and remove the rear brake shoe.
WARNING: Immediately after removing the pads, secure the pistons of the working cylinder in any available way (for example, tie them with a rubber band or tie them with wire), otherwise the pistons may be pushed out of the cylinder by the expansion spring and brake fluid will leak from the hydraulic system.
WARNING: Do not apply the brake pedal with the pads removed, as this will force the pistons out of the slave cylinder and cause brake fluid to leak out of the hydraulic system.
Fig. 9.5. Rear wheel brake mechanism parts (right side brake mechanism parts are shown): 1 – rear brake shoe of the rear wheel brake mechanism; 2 – clamping bracket; 3 – parking brake release lever; 4 – spacer bar with gap adjuster; 5 – upper tension spring; 6 – working cylinder; 7 – Rear parking brake cable extension; 8 – front brake shoe of the rear wheel; 9 – lower tension spring
15. Clean and inspect the brake mechanism components (Fig. 9.5). Replace any deformed or heavily corroded components. Replace any springs that are heavily stretched, have lost their elasticity, or are bent.
HELPFUL TIP: Replace the brake calipers with new ones every time you disassemble the brake mechanism.
USEFUL TIP: When replacing brake pads, we recommend replacing the spacer bars together with the clearance adjusters if they have begun to corrode, as corrosion may cause the clearance adjuster to fail during further use.
NOTE: The left brake adjuster parts are not interchangeable with the right brake adjuster parts - do not confuse them!
NOTE: The front 8 (see Fig. 9.5) and rear 1 shoes of the rear brake mechanism are different in design (the parking brake release lever is attached to the rear shoe by means of a rivet axle, and the friction lining of the front shoe is shorter but thicker than that of the rear shoe). In addition, the rear brake shoes are distinguished as left and right.
16. Apply high-melting grease for brake mechanisms to the friction areas of the front and rear brake pads on the brake shield.
17. Release the pistons of the working cylinder from the locking device, squeeze the pistons of the working cylinder with sliding pliers and install the brake pads in the reverse order of removal.
WARNING: Be aware that retracting the pistons into the cylinder will increase the brake fluid level in the master cylinder reservoir. If necessary, pump out the fluid.
18. Install the brake drum (see "Removing and installing the brake drum").
19. Adjust the clearance between the brake shoes and the drum by pressing the brake pedal 10-15 times. Each time you press it, you should hear the adjuster click. If the clicking stops, the clearance is set.
20. Replace the wheel. Check that it rotates easily.
21. Replace the brake pads of the brake mechanism of the other wheel in the same way.
22. After installing the brake pads, adjust the parking brake system (see "Adjusting the Parking Brake Drive").