Brake Booster: Installation

WARNING: This page is about a different car, the 2015 Subaru XV Crosstrek and 2015 Subaru Impreza. However, it is still accessible from the selected car via links, so may be relevant.

Check and adjust the operating rod of the vacuum booster assembly.
1. Measure the length between the vacuum booster assembly mounting surface and clevis pin hole.
2. If it is not within the specification, loosen the lock nut, rotate the vacuum booster assembly operating rod to adjust the rod length.
  Specification L:
  
  136.3 mm (5.37 in)
  
  Fig 1: Identifying Vacuum Booster Assembly Of Mounting Surface And Clevis Pin Hole Dimension
  Courtesy of SUBARU OF AMERICA, INC.
Install each part in the reverse order of removal.
CAUTION:
- Apply grease to the snap pin to prevent the operating rod from wear.
- Replace the clevis pin with new parts, and apply thin coat of NIGTIGHT LYW No. 2 grease to the clevis pin.
- When installing the master cylinder assembly, replace the seal sub assembly with a new part, and install it to the vacuum booster assembly.
Fig 2: Identifying Seal Sub Assembly To Surface Area
Courtesy of SUBARU OF AMERICA, INC.

Tightening torque:

Vacuum booster assembly: 18 N.m (1.84 kgf-m, 13.3 ft-lb)

Master cylinder assembly: 13 N.m (1.33 kgf-m, 9.6 ft-lb)

Brake pipe flare nut: 19 N.m (1.94 kgf-m, 14.0 ft-lb)

Operating lock nut: 22 N.m (2.24 kgf-m, 16.2 ft-lb)

Knee airbag module: 7.5 N.m (0.76 kgf-m, 5.5 ft-lb)
Install the air conditioner pipe. < Ref. to AIR CONDITIONING UNIT , COMPONENT, General Description.>
Charge refrigerant. < Ref. to PROCEDURE , Refrigerant Charging Procedure.>
Bleed air from the brake system. < Ref. to PROCEDURE , Air Bleeding.>
Perform a road test to make sure the brakes do not drag.