Vacuum Brake Booster: Service and Repair

Brake Booster
REMOVAL
Remove or disconnect the following parts at engine compartment.
Disconnect the connector for brake fluid level indicator.
Remove the brake pipes from master cylinder.
Remove the master cylinder installing nuts.
Disconnect the vacuum hose from brake booster.
Remove the following parts from pedal bracket.
Snap pin and clevis pin.
Four brake booster installing nuts.





(1) Nuts
(2) Clevis pin
(3) Snap pin
(4) Operating rod

Remove the brake booster while shunning brake pipes.

Note:
^ Be careful not to drop the brake booster. The brake booster should be discarded if it has been dropped.
^ Use special care when handling the operating rod.
If excessive force is applied to the operating rod, sufficient to cause a change in the angle in excess of ±3°, it may result in damage to the power piston cylinder.
^ Use care when placing the brake booster on floor.
^ Do not change the push rod length. If it has been changed, reset the projected length "L" to standard length.
Standard L: 10.05 mm (0.40 inch)





Important: If external force is applied from above when the brake booster is placed in this position, the resin portion as indicated by "P", may be damaged.





(1) Force

INSTALLATION
Adjust the operating rod of brake booster.
Standard L: 144.6 mm (5.69 inch)
If it is not within specified value, adjust it by adjusting the brake booster operating rod.





Mount the brake booster in position.
Connect the operating rod to brake pedal with clevis pin and snap pin.





(1) Nuts
(2) Clevis pin
(3) Snap pin
(4) Operating rod

Connect the vacuum hose to brake booster.





Mount the master cylinder onto brake booster.
Connect the brake pipes to master cylinder.
Connect the electric connector for brake fluid level indicator.
Measure the clearance between threaded end of stop light switch and stopper. If it is not within specified value, adjust it by adjusting the position of stop light switch.
If it is not within specified value, adjust it by adjusting the position of stop light switch.

Important: Be careful not to rotate the stop light switch.

Stop light switch clearance A: 0.3 mm (0.012 inch)





Apply grease to operating rod connecting pin to prevent it from wearing.
Bleed air from the brake system.
Tightening torque (Air bleeder screw): 8 Nm (0.8 kgf-m, 5.8 ft. lbs.)
Conduct road tests to ensure brakes do not drag.