Discovery I (LJ) V8-3.9L (1994)
Vacuum Brake Booster: Service and Repair
REMOVE
NOTE: The filter, non-return valve and grommet, are the only serviceable components, in event of failure or damage fit a new unit.
1. Disconnect the battery negative lead.
2. Disconnect electrical plug to low fluid level switch.
3. Thoroughly clean immediate area around all master cylinder outlet ports. Remove each brake pipe, sealing each pipe and outlet port to prevent
ingress of foreign matter.
4. Disconnect vacuum supply hose to servo.
5. Remove lower dash panel to gain access to servo push rod to brake pedal.
Brake Pedal Linkage
6. Remove clevis pin securing servo push rod to brake pedal.
7. Remove two nuts and plain washers securing servo.
8. Remove servo and master cylinder assembly.
9. Drain brake fluid into a suitable container. (If master cylinder is kept horizontal it is not necessary to drain fluid).
Brake Servo
10. Detach spacer from pedal box mounting face of servo.
NOTE: Retain spacer for reassembly. The spacer ensures stringent pedal to servo operating dimensions are maintained.
11. Remove master cylinder from existing servo and refit to new servo, if fitting new unit.
REFIT
1. Fit spacer to servo.
2. Fit servo to pedal box.
3. Lightly grease brake pedal around area servo push rod pivots.
4. Fit push rod to lower hole of brake pedal. Fit clevis pin and clip.
5. Secure servo with two nuts and plain washers. Tighten nuts to 26 Nm (19 ft lb).
6. Refit lower dash panel.
7. Fit master cylinder to servo, refit nuts, plain and spring washers. Tighten nuts to 26 Nm (19 ft lb).
8. Remove all sealing plugs. Refit brake pipes to respective ports. Tighten brake pipes to 15 Nm (11 ft lb).