Master Cylinder

NOTE:

When the master cylinder is disassembled or the reservoir tank is empty, bleed the master cylinder.
If bleeding of the master cylinder is not necessary, omit the following procedures, and perform bleeding of the brake line. Refer to BRAKE LINE , PROCEDURE, Air Bleeding .

Fill the reservoir tank of the master cylinder with brake fluid.
NOTE: While bleeding air, keep the reservoir tank filled with brake fluid to prevent entry of air.
Disconnect the brake line at primary and secondary sides.
Wrap the master cylinder with a plastic bag.
Depress the brake pedal slowly and hold it.

Fig 1: Depressing Brake Pedal
Courtesy of SUBARU OF AMERICA, INC.

NOTE: If the vehicle is equipped with a brake assist mechanism, the following may result when the brake pedal is depressed. They are normal conditions that occur when the mechanism is performing properly.
- Brake feel is soft when brake pedal is depressed hard or quicker than usual.
- A light crack is heard when brake pedal is depressed hard or quicker than usual.
Plug the outlet plug with your finger, and then release the brake pedal.

Fig 2: Depressing Brake Pedal
Courtesy of SUBARU OF AMERICA, INC.
Repeat the step 4) and 5) several times.
Remove the plastic bag.
Install the brake pipe to the master cylinder.
Tightening torque:

19 N.m (1.9 kgf-m, 14.0 ft-lb)
Bleed air from the brake line. Refer to BRAKE LINE , PROCEDURE, Air Bleeding .