Brake Booster: Installation

WARNING: This page is about a different car, the 2012 Subaru Outback and 2012 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.

Check and adjust the operating rod of the brake booster.
1. Measure the length between the brake booster mounting surface and clevis pin hole.
2. If it is not within specification, loosen the lock nut, rotate the brake booster operating rod to adjust the rod length.
Specification L:

136.5 mm (5.37 in)

Fig 1: Measuring Length Between Brake Booster Mounting Surface And Clevis Pin Hole
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 brake booster.
  
  Fig 2: Installing Seal Sub Assembly
  Courtesy of SUBARU OF AMERICA, INC.
- Install the bracket at the position with sufficient clearance that it does not contact with the check valve.
- Be sure to loosen the master cylinder mounting nut while holding the bracket with hand. Otherwise the bracket may deform.
Fig 3: Installing Master Cylinder Assembly And Bracket
Courtesy of SUBARU OF AMERICA, INC.

Tightening torque:

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

Master cylinder: 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)
Bleed air from the brake system. Refer to , PROCEDURE , Air Bleeding.
Perform a road test to make sure the brakes do not drag.