The replacement of the booster pump must be carried out in the following order. Pump out the brake fluid from the expansion tank. Remove the mudguard of the left front wheel, for which remove the rivets (1, Fig. 11.71) and unscrew the bolts (2).
Remove the bolt (5, see Fig. 11.70) fastening the pump bracket to the body. Unlock and disconnect the shock absorber (top arrow, Fig. 11.72) pump. Place a rag in the area of the brake pipe fittings. Mark the installation locations and disconnect the pipes (see bottom arrows) brake drive from the booster pump.
Remove the brake fluid spill. Remove the booster pump from the rubber shock absorbers, together with the casing and bracket. Unscrew the bolts (13), reposition the protective casing (7) and bracket (2).
The installation of the booster pump should be carried out in the reverse order, while it is necessary. Tighten the bolts securing the protective casing and bracket on the pump to a torque of 8.0 N·m (0.8 kgf·m).
Connect the brake lines according to the markings on the booster pump:
- HZ, line to master brake cylinder;
- VA, pipeline to the brake drive expansion tank.
Tighten the union nuts of the brake pipe fittings to a torque of 14 N·m (1.4 kgf·m). Tighten the bolt securing the pump bracket to the body to a torque of 8.0 N·m (0.8 kgf·m).
Upon completion of the work:
- connect the brake fluid changer;
- activate the booster pump using the "DIS" system;
- bleed the front wheel drive circuit.
[The original source of the article is on the website www.bmwman.ru]