Brake systems · Brakes – hydraulics · Assembly overview – brake booster/brake master cylinder
Brake booster/brake master cylinder (left-hand drive vehicle) – assembly overview and fastening
Complete brake master cylinders and brake boosters can be renewed independently of each other.
- 1 Cap
- 2 Brake fluid level warning contact - F34-
- 3 Brake fluid reservoir
- 4 Sealing plug
- 5 Brake booster
- On petrol engines, the required vacuum is obtained at the intake connecting piece.
- Diesel engines are fitted with a vacuum pump to create the required vacuum.
- Checking function
- With engine switched off, depress brake pedal firmly several times (to exhaust vacuum in unit).
- Now step on and hold brake pedal with medium pressure and start engine. If the brake booster is functioning properly, the brake pedal will be felt to go down as the servo takes effect.
- Replace completely in the event of a fault (before doing so, check brake booster vacuum system) ⇒ 5.4 Checking brake booster vacuum system
- Non-return valve (in vacuum hose) functional check ⇒ 5.5 Checking non-return valve.
- Separating from brake pedal ⇒ 5.1.1 Separating brake pedal from brake booster
- Removing and installing ⇒ 7 Removing and installing brake booster.
- 6 Seal
- For brake booster.
- 7 Self-locking hexagon nut, 25 Nm
- Always renew after removing.
- 8 Sealing ring
- Renew.
- 9 Brake master cylinder
- Cannot be repaired. If faulty, renew as a complete unit.
- 10 Brake light switch - F-
- Including brake pedal switch - F47-.
- Removing and installing ⇒ 5.8 Removing and installing brake light switch - F-, left-hand drive.
- 11 Torx bolt, 7 Nm
- 12 Self-locking hexagon nut, 25 Nm
- Always renew after removing.
- 13 Pin
- 14 Sealing plug
- Moisten with brake fluid and press into brake master cylinder.