11.12.1. Blocks of disk brakes


Scheme of operation of the indicator of wear of blocks

1. New block
2. Worn-out
3. Disk
4. Indicator
5. Block

On the most part of cars the indicator of wear of blocks is provided. If when using of brakes characteristic squeal sounds, then check wear of blocks. If the indicator adjoins to a brake disk, then blocks should be replaced.


Residual thickness of blocks can be checked through a window in a support (1 – a support finger, 2 – a window).
For more detailed survey (uniformity of wear on the planes and checks of a state) should remove blocks. Extreme residual thickness of blocks is 1 mm (1983-86) and 2 mm (since 1987).

Removal and installation
PERFORMANCE ORDER
1. Lift a front of the car and remove a wheel.


2. Turn away the lower finger, cast away a support and fix. Do not allow removal of protective lubricant of a finger of a support, or hit of dirt on it.


3. Remove blocks, plates and brackets, remember an arrangement of these details (1 – a bracket, 2 – an internal plate, 3 – an external plate).

Installation
The correct orientation of antinoise plates and blocks at assembly

1. Internal plate
2. Internal block
3. External block
4. External plate

PERFORMANCE ORDER
1. Drown the piston in the support cylinder by means of a clamp, watching liquid level in a tank (at installation of new blocks the piston should be taken away on considerable distance).
2. Establish plates and brackets in a former order.
3. Establish blocks on a support. If the top and lower brackets are provided, then they should be replaced together with blocks.
4. Establish a support, a wheel and lower the car.
5. Press a pedal several times that blocks nestled on a disk. Check liquid level, if necessary add.
6. Start the engine and again press several times a brake pedal, check rigidity of a pedal. At the first 15 km of a run with new blocks avoid sharp braking.