Assembling the drum brake mechanism of the right rear wheel
1 - Automatic regulator lever; 2 - Assembly of the regulator; 3 - Wheel cylinder; 4 - Upper coupling spring; 5 - Guide spring; 6 - Spring of the automatic regulator; 7 - Lower coupling spring; 8 - Parking brake cable; 9 - Executive lever of the parking brake drive
Attention! The replacement of the shoes must be carried out simultaneously on both brake mechanisms. See also the warning at the beginning of the Section Removal and installation of brake calipers!
Simultaneously with the replacement of the brake shoes, their coupling and guide springs should also be replaced, which, as a result of constant cyclic mechanical and thermal loads, stretch / sag over time, stopping developing the required force, which leads to sticking of the brakes and accelerated wear of the drums.
1. Loosen rear wheel nuts. Jack up the back of the car and place it on jack stands. Support the front wheels with wheel chocks. Remove the rear wheels and release the parking brake.
2. Remove the brake drum from the hub. The drum should be removed fairly freely, but in case of difficulty, gently tap it with a soft-faced hammer, or screw a pair of M8 bolts into the threaded holes. If the drum still cannot be removed, the brake shoes should be pressed from its working surface. Remove the rubber plug from the brake shield, insert a screwdriver into the opened hole and use it to remove the self-regulator lever from the adjusting sprocket. Rotate the sprocket with a second screwdriver until the drum is completely free.
3. It is easier to replace the shoes after removing the hub assembly from the axle trunnion (remove the wheel bearing cap, give the spindle nut and remove the washer (see chapter Suspension and steering).
4. Acting in accordance with the instructions given in the illustrations, check the condition of the components and replace the brake shoes. Act strictly in the specified order. Remember that all four shoes of both brakes must be replaced at the same time.
5. Before installing the drum, check it for nicks, gouges, overheating, and other defects. If serious damage is detected, the traces of which cannot be eliminated by treating the drum with fine-grained sandpaper, the drum should be given to the groove (in compliance with the maximum allowable repair diameter).
Note. The compilers of this Guide recommend turning drums, regardless of their condition, in order to remove all kinds of defects and eliminate ovality. If the reaming of the drum cannot be done without violating the requirements for the maximum allowable inner diameter (knocked out on the drum, you will have to replace it. If turning the drums is not possible, at least thoroughly clean their working surfaces with fine-grained sandpaper.
6. Reinstall the hub assembly with wheel bearing, put on the washer and screw on the new spindle nut, tightening it to the required torque (see Specifications to Chapter Suspension and steering).
7. Replace the drum. Insert a screwdriver into the hole in the brake shield and, turning the regulator sprocket, press the shoes against the working surfaces of the drum, then return the sprocket back a little so that the drum begins to rotate freely (pre-adjustment).
8. Replace the wheel, then lower the vehicle to the ground and tighten the wheel nuts to the required torque (see Specifications to Chapter Settings and ongoing maintenance).
9. Brake the car several times when driving it both forward and reverse in order to automatically adjust the brake mechanisms.
10. Before starting the operation of the car, make sure that the brakes are working properly.