Brake Master Cylinder And Vacuum Brake Booster Overview: Notes
WARNING:
With the introduction of the new Bosch 5 ABS/EDL systems (1996 m.y REPAIR INSTRUCTIONS AND SAFETY PRECAUTIONS, BOSCH 5, FROM MY 96 the brake master cylinder has been modified. This change is cannot be recognized from the external shape. If the wrong master cylinder is installed, this may result in a loss of vehicle safety. Refer to the part number for identification.
WARNING:
- Brake master cylinder cannot be disassembled, and is not repairable.
- Use only new brake fluid. Refer to label on brake fluid reservoir.
- Brake line connections ABS HYDRAULIC UNIT OVERVIEW .
- Self-locking nut
- Always replace
- 25 Nm (18 ft lb)
- Pedal bracket
- Instrument panel
- Gasket
- Replace after removing and installing brake pressure regulator
- Pin
- Install in clevis
- Sleeve
- Install in clevis
- Install brake pedal return spring in sleeve
- Clip
- Install on pin
- Clevis
- Adjusting Adjusting clevis
- Lock nut
- Brake booster
- Checking:
-- Press down forcefully on brake several times with engine off to build up pressure.
-- Hold brake pedal in braking position with average foot pressure and start engine.
-- If brake booster is functioning correctly, brake pedal will drop noticeably under foot (boost goes into effect).
- Replace complete brake booster if malfunctioning
- Boost factor: 3.85:1
- Diameter: 254 mm (10.00 in.)
- Checking:
- Filler cap
- Gasket
- Install in cap
- Brake fluid reservoir with float for brake fluid level warning switch
- Fill brake fluid to MAX mark
- Connection for clutch hydraulic system on side
- Note label on brake fluid reservoir before topping off brake fluid
- Brake fluid total capacity: approx. 0.6 L (0.63 qt.) in brake system
Checking function of brake fluid warning switch/light:
- Up to 07.92 production: With ignition on, press forcefully on center of filler cap (diaphragm); brake fluid level warning light on instrument cluster comes on along with a warning buzzer
- From 07.92 production (diaphragm is eliminated): remove yellow filler cap with brake symbol; with ignition on, press down on visible filter screen by hand
- Rubber plug
- Brake master cylinder
- Diameter: 23.81 mm (0.937 in.)
- Before removing, disconnect vacuum line from brake booster
- Remove or install brake master cylinder without tipping to prevent damage to the brake booster
- Always replace complete brake master cylinder
- Provided with two connections on left side
- On right side, non-functional connection (blind connection)
- Washer
- Nut
- 25 Nm (18 ft lb)
- O-ring
- Always replace after removing the brake booster or brake master cylinder
- Vacuum line with check valves
- Checking function of check valves: it must be possible to blow through the valve in the direction of the arrow; the valve must be closed in the opposite direction
- Install in brake booster
- Hose clamp
- Vacuum hose
- Install at intake manifold and fasten with hose clamp
- Hose clamp