9.3.1. Replacement of brake cylinders and brake shoes

Fig. 7.2. Drum brake mechanism of a back wheel of the LT18C type: 1 — a dustproof cuff; 2 — the piston; 3 — a cuff; 4 — the brake cylinder; 5 — the union for pumping; 6 — a spring; 7 — a cable of the parking brake; 8, 12, 13 — a basic rack of a block with a spring and a cup; 9 — a brake board; 10 — squeezing the lever; 11 — a squeezing brake shoe; 14 — the lower coupling spring of blocks; 15 — a spring of the mechanism of automatic adjustment of a gap; 16 — the brake drum; 17 — a clamping brake shoe; 18 — the mechanism of automatic adjustment of a gap; 19 — the top coupling spring of blocks

During the work be guided by fig. 7.2 and 7.8.

Fig. 7.8. Drum brake mechanism of back wheels: 1 — a cable of the parking brake; 2 — the lower coupling spring; 3 — the top coupling spring; 4 — a rack with a clamping spring and a cup; 5 — a razzhimny brake shoe; 6 — a clamping brake shoe; 7 — the mechanism of automatic adjustment of a gap; 8 — the wheel brake cylinder

When replacing the brake drum or wheel brake cylinder also replace brake shoes.

Fig. 7.9. Removal of the brake drum with use of two bolts of M8x1,25

Lift a back part of the car and put it on supports. Remove wheels, having noted their situation concerning naves. Lower the lever of the parking brake system. From an external part of a brake board by means of the screw-driver inserted into a special opening wring out the lever of automatic adjustment of a gap between a drum and blocks. In technological openings wrap two bolts of M8x1,25 (fig. 7.9) and, evenly tightening them, remove the brake drum from blocks.

Remove a protective cap from a nave, take out the forelock and turn off a nut of fastening of a nave. Remove a nave. Remove a spring of the mechanism of automatic adjustment of a gap. Disconnect and remove the top and lower coupling springs of blocks. Remove basic racks of brake shoes assembled. Disconnect a cable of the drive of the parking brake. Remove a clamping brake shoe, then a squeezing block. Take out the mechanism of automatic control of a gap. Disconnect the pipeline from the wheel cylinder, having taken measures against an effluence of brake fluid.

For removal of the brake cylinder turn out bolts of its fastening to a brake board. Clear details of oil and dirt. Measure the sizes of the brake drum and compare them with provided in subsection. "General information".

You make assembly as it should be, the return to dismantling. Upon termination of assembly remove air from system of a hydraulic actuator and adjust the drive of the parking brake.