Note: It is difficult to measure the thickness of a completely worn brake shoe lining with sufficient accuracy. Therefore, measure the total 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.
Caution: Do not use gasoline, diesel fuel or any other mineral solvents to clean the brakes.
Attention! 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 1st 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. Place the vehicle on a support and remove the wheel from the corresponding side.
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 "Removal and installation the brake drum").
6. Remove the rear mount of the brake shoe clearance adjuster spring stop by prying it up with a screwdriver.
7. Similarly, remove the front spring stop mount…
8. …and remove the spring stop from the spacer bar.
9. Tighten the gap adjuster toothed nut until it stops, turning it clockwise.
10. Move the front shoe back a little and remove the spacer bar assembly with the clearance adjuster.
11. Using a screwdriver, pry off the bent end of the upper tension spring from the rear shoe with pliers, and unhook its other end from the front shoe…
12. …and remove the spring.
13. Remove the lower tension spring in the same way.
14. Rotate down and remove the front brake shoe retaining clip by pulling it towards you.
15. Remove the brake caliper support from the hole in the brake shield…
16. …and remove the front brake shoe.
17. Remove the rear brake shoe retaining clip.
18. Move the rear cable extension end back into the release lever slot until it aligns with the slot in the lever…
19. …disconnect the cable end from the release lever and remove the rear brake shoe.
Attention! 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) to prevent the pistons from being pushed out of the cylinders.
Fig. 9.6. Rear wheel brake mechanism parts: 1 – front brake shoe of the rear wheel; 2 – upper tension spring; 3 – spacer bar with gap adjuster; 4 – rear brake shoe of the rear wheel; 5, 11 – clamp bracket posts; 6 – parking brake release lever; 7, 10 – clamping brackets; 8 – lower tension spring; 9 – spring stop of the ratchet mechanism of the gap adjuster
20. Clean and inspect the brake mechanism components (Fig. 9.6). Replace any deformed or heavily corroded components. Replace any springs that are heavily stretched, have lost their elasticity, or are bent.
Note: Replace the brake calipers with new ones each time the brake mechanism is disassembled.
Note: 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 adjusters to fail during further use.
Note: The left brake adjuster parts are not interchangeable with the right brake adjuster parts - do not mix them up!
Note. The front 1 (see Fig. 9.6) and rear 4 brake shoes of the rear brake mechanism are different in design (the parking brake release lever is attached to the rear shoe with 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.
21. Apply high-melting grease for brake mechanisms to the friction areas of the front and rear brake pads on the brake shield.
22. 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.
Caution! Keep in mind that when the pistons are pressed into the cylinder, the brake fluid level in the master cylinder reservoir increases. If necessary, pump out the fluid.
23. Install the brake drum (see "Removal and installation the brake drum").
24. 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.
25. Replace the wheel. Check that it rotates easily.
26. Replace the brake pads of the brake mechanism of the other wheel in the same way.
27. After installing the brake pads, adjust the parking brake system (see "Adjusting the parking brake drive").