NOTE: The brake pipe mounting nuts are usually very tight. When trying to loosen them with a regular wrench, the edges of the nuts are crushed, so we recommend using special wrenches for brake pipes.
1. Disconnect the wire from the negative terminal of the battery.
2. Unscrew the cap of the master brake cylinder reservoir...
3. ...grasp the edge of the mesh filter with pliers...
4. ...remove it from the tank...
5. ...and pump out the brake fluid from the reservoir, for example, with a large medical syringe. Install the plug to prevent dirt from getting into the master cylinder reservoir.
6. Squeeze the clamps of the brake fluid level sensor wiring harness connector...
7. ...disconnect the connector from the sensor.
8. On a vehicle with a manual transmission, disconnect the hose from the reservoir to the clutch master cylinder.
USEFUL TIP: Immediately after disconnecting the hose from the reservoir, plug its opening without lowering the hose down. There will be some working fluid left in the hose, then after installing the reservoir and connecting the hose to it, there will be no need to bleed air from the clutch release hydraulic drive.
NOTE: On vehicles with automatic transmission, the nipple is plugged.
9. Remove the battery (see "Removal and installation the battery").
10. Unscrew the nuts securing the two pipelines to the cylinder...
11. ...and move the pipes to the side.
HELPFUL TIP: Seal the pipes using any available method (for example, by putting protective caps on their ends to release air), to prevent brake fluid from leaking out.
12. Unscrew the two nuts securing the master brake cylinder to the vacuum booster...
13. ... remove the nuts from the brake booster mounting bolts...
14. ...then remove the master brake cylinder assembly with the reservoir.
15. If the new master cylinder does not have a reservoir or it is necessary to replace the rubber connecting bushings of the reservoir, remove the reservoir by pressing out the pin of its fastening and removing its pipes from the connecting bushings (see "Replacing the brake master cylinder reservoir").
16. If during operation a leak of brake fluid was observed through the connecting bushings, remove the bushings from the holes in the cylinder body.
WARNING: Do not reuse coupling bushings, replace with new ones.
17. Remove the rubber sealing ring from the master cylinder housing.
CAUTION: Replace the master cylinder O-ring with a new one each time the connection is disassembled.
18. If during operation the brake fluid level sensor fails, to replace it, press the lock...
19. ...and remove the sensor from the tank.
20. Install the brake master cylinder and all removed parts in the reverse order of removal, fill with brake fluid and bleed the system, see. "Bleeding the hydraulic brake system").
[The original article is on the website CHEVYMAN.ru]