Vacuum Brake Booster: Service and Repair

REMOVAL
1. Disconnect battery ground cable.
2. Exhaust residual vacuum by pressing brake pedal four to five times.
3. Remove brake master cylinder mounting nuts from power brake booster. Move it aside without disturbing hydraulic tubes. It is not necessary to disconnect brake tubes, but be careful not to kink brake tubes. Tubes will need to be replaced if they are kinked.
4. Disconnect manifold vacuum hose from power brake booster check valve.
5. Working inside vehicle below dash panel, remove stoplight switch connector. Remove stoplight switch retaining pin and spacer.
6. Slide stoplight switch from brake pedal pin just far enough for outer plate of stoplight switch to clear pin. Then remove stoplight switch from pin. Be careful not to damage stoplight switch during removal.
7. Remove booster-to-dash panel retaining nuts. Slide booster push rod and brake master cylinder push rod bushing off brake pedal pin.
8. Remove power brake booster from dash panel by sliding push rod out from engine side of dash Panel.




INSTALLATION
1. Place power brake booster in position.
2. Working inside vehicle, position booster push rod and brake master cylinder push rod bushing on brake pedal pin. Secure power brake booster to dash panel with self-locking nuts. Tighten to 21-29 Nm (16-21 ft. lbs.).
3. Position stoplight switch so that it straddles booster push rod with switch slot toward pedal blade and hole just clearing pin. Slide stoplight switch completely onto pin. Be careful not to bend or deform stoplight switch.
4. Install brake master cylinder push rod spacers on pin and secure all parts to pin with hairpin retainer. Make sure retainer is fully installed and locked over pedal pin. Install stoplight switch wiring connector on stoplight switch.
5. Connect manifold vacuum hose to power brake booster check valve using hose clamp.
6. Position brake master cylinder on booster studs. Install locking nuts. Gradually tighten retaining nuts to 21-29 Nm (16-21 ft. lbs.).
7. Connect battery ground cable. Start engine and check power brake function.