Power Brake Assist: Description and Operation

Brake Master Cylinder And Brake Servo, Assembly

WARNING:
^ Do not re-use fasteners that are worn or deformed in normal use.
^ Some fasteners are designed to be used only once, and are unreliable and may fail if used a second time. This includes, but is not limited to, nuts, bolts, washers, circlips and cotter pins. Always follow recommendations-replace these fasteners with new parts where indicated, and any other time it is deemed necessary by inspection.

When working with brake fluid, observe the relevant safety precautions and notes.

Notes:
^ Vehicles may be equipped with brake master cylinders and brake servos of various makes. Complete master cylinders and brake servos can be independently replaced.
^ Brake master cylinders cannot be disassembled or repaired.
^ Use only new brake fluid. Refer to label on the brake fluid reservoir
^ Brake line connections to master cylinder.





1. T45 Torx(R)
^ 25 Nm (18 ft. lbs.)
2. Self-locking nut
^ 49 Nm (36 ft. lbs.)
3. Brake master cylinder
^ Diameter: 23.81 mm (0.937 inch)
^ Cannot be repaired. If malfunctioning, replace as complete part only.
^ Refer to Removing and installing
4. Brake line
^ Brake master cylinder/secondary piston circuit to hydraulic control unit
5. Brake line
^ Brake master cylinder/primary piston circuit to hydraulic control unit
6. Seal
^ Always replace
7. Brake servo
^ On gasoline engines vacuum is supplied from intake manifold
^ Check valve in vacuum hose -9-
^ Refer to Removing and installing
Functional check:
- With engine switched off, depress brake pedal firmly several times (to deplete vacuum in brake servo).
- Depress and hold brake pedal with average foot pressure and start engine. If servo unit is working properly, pedal will be felt to give slightly under foot (servo assistance becomes effective).
If malfunctioning:
- Replace as complete part only.
8. Seal
9. Vacuum hose
^ Insert into brake servo
10. Brake fluid reservoir
11. Cap
12. Sealing plugs
13. Supply hose
^ Where applicable
^ From brake fluid reservoir to clutch master cylinder
14. Bulkhead