Attention! On vehicles equipped with «ASC+T/DSC» it is forbidden to disconnect the pipelines connecting to the hydraulic unit and the main brake cylinder.
In the brake system, plastic-coated injection pipes are used as rigid connections. Brake hoses create a flexible, incompressible connection between the body and the suspension. The design of the pipelines of the drive is shown in Figure 11.54 of the front brake mechanisms and in Figure 11.55 - of the rear brake mechanisms.
Attention! When changing pipes, take care not to damage the plastic layer.
Union nuts must strictly match the fittings of the connections. flanging (flaring) and bending of the pipeline is carried out in special devices. When bending and flanging, use the removed pipeline as a sample.
Lay the pipelines of the brake drive in their regular places, eliminating friction on the elements of the car.
Replacement of the brake pipeline is necessary for carrying out in a following order. Place the car on a lift, viewing hole or stands. Lightly press the brake pedal and lock it (see fig. 11.3). To replace pipelines, unscrew the union nuts (tips, fittings) and remove the pipe clamps on the body. Seal the joints of pipelines with plugs or caps.
Brake pipelines are delivered in a straight form, the required length and with connectors, nuts (fittings). Install the new pipeline in place of the old one, preliminarily bending it with a device «34.5.100» (pic. 11.56). Use the removed pipeline as a sample. Tighten the union nuts of the pipeline fittings with a torque of 14 Nm (1.4 kgf·m).
After replacing the pipelines, bleed the brake system and check the safety of the brake system.
Safety control of the brake system consists in checking:
- fastening of brake pipelines;
- fixing brake hoses in holders;
- tightening of bleed fittings;
- brake fluid level in the compensation tank;
- tightness of the system on a running engine - when you press the brake pedal with a force of 20–30 kgf and hold it for 10 seconds, there should not be any «drawdown» brake pedals;
- tightness of all connections of the car.