Q45 V8-4494cc 4.5L DOHC (VH45) (1992)
Vacuum Brake Booster: Service and Repair
Removal/Installation
Fig. 2 Brake Booster Replacement.
Fig. 3 Checking Output Rod Length
1.
Connect tube to bleeder valve.
2.
Open bleeder valve, drain fluid by depressing brake pedal until master cylinder is empty.
3.
Remove brake line flare nuts, then master cylinder attaching nuts.
4.
Remove clevis pin, Figs. 1 and 2.
5.
Remove brake booster attaching nuts, then remove booster.
6.
Reverse procedure to install noting the following:
a. Check output rod length by applying 19.69 inch Hg. vacuum with a suitable vacuum pump.
b. Measure output rod length as shown in Fig. 3. Length should be 0.4045-0.4144 inch.
c. On G20 model Torque booster attaching nuts to 9-12 ft. lbs., and 5.8-8.0 ft. lbs on M30 and Q45 models.
d. Bleed system, refer to MAINTENANCE PROCEDURES/BRAKE SYSTEM BLEED.