Subaru Legacy IV (2008 year). Service manual - part 953

BR-24

Rear Disc Brake Assembly

BRAKE

E: INSPECTION

1) Repair or replace the faulty parts.
2) Check the caliper body and piston for uneven
wear, damage or rust.
3) Check the rubber parts for damage or deteriora-
tion.

BR-25

Master Cylinder

BRAKE

8. Master Cylinder

A: REMOVAL

CAUTION:
Do not allow brake fluid to come in contact with
vehicle body. If it does, wash off with water and
wipe away completely.
1) Drain brake fluid from the reservoir tank com-
pletely.
2) Disconnect the harness connector of the fluid
level gauge.
3) Remove the brake pipe from the master cylinder.
4) Remove the master cylinder mounting nuts, and
remove the master cylinder from the brake booster.

B: INSTALLATION

1) Replace the O-ring for the master cylinder with a
new part.

CAUTION:
Be careful not to install the O-ring in the wrong
location.

2) Install in the reverse order of removal.

Tightening torque:

Master cylinder mounting nut

13 N·m (1.3 kgf-m, 9.6 ft-lb)

Piping flare nut
Model with ABS

15 N·m (1.5 kgf-m, 10.8 ft-lb)

Model with VDC

19 N·m (1.9 kgf-m, 14.0 ft-lb)

CAUTION:
Be sure to use recommended brake fluid.
3) Bleed air from brake system. <Ref. to BR-32,
PROCEDURE, Air Bleeding.>

C: REPLACEMENT

1) Remove mud and dirt from the surface of brake
master cylinder.
2) Secure the master cylinder in a vise.

NOTE:
To avoid damaging the master cylinder, place be-
tween aluminum plates or other material when
holding with a vise.
3) Remove the pin which secures the master cylin-
der and reservoir tank, then remove the reservoir
tank and seal.

4) While pushing in the primary piston, remove the
C-ring using pliers.

5) While pushing in the primary piston, remove the
straight pin from the port on the reservoir tank at-
tachment location using a magnet pick-up tool.

6) Extract the primary piston assembly and sec-
ondary piston assembly straight out while taking
care not to scratch the inner surface of the cylinder.

(1) Primary piston

(2) O-ring

(3) Do not install the O-ring on this groove.

(1)

(2)

(3)

BR-00363

(1) Straight pin

BR-00364

BR-00169

(1)

BR-00069

BR-26

Master Cylinder

BRAKE

7) Clean the inside of master cylinder with brake
fluid. Check the inside of the cylinder for damage,
deformation and wear. Replace the master cylinder
as assembly if faulty.
8) Apply brake fluid to the inner surface of master
cylinder and piston assembly.
9) Make sure that the inner surface of master cylin-
der and the piston assembly are free of foreign
matter. Install the primary piston assembly and the
secondary piston assembly to master cylinder,
while taking care not to scratch the master cylinder
inner surface.
10) While pushing-in the primary piston, install the
cylinder pin.
11) While pushing-in the primary piston, install the
C-ring to the groove using pliers.

CAUTION:
Make sure the C-ring is installed to the groove
securely.
12) Install the seal to reservoir tank.

13) Install the reservoir tank to the master cylinder,
and secure with pin.

14) Replace the O-ring for the master cylinder with
a new part.

D: INSPECTION

Inspect for oil leakage from the master cylinder.

NOTE:
After replacing the piston kit, if an oil leakage is
found even though there is no damage or scratches
on the inside of the cylinder, the master cylinder in-
ner wall may be worn. In this case, replace the
master cylinder as an assembly.

(1) Seal

BR-00169

(1)

BR-00072

(1) Primary piston

(2) O-ring

(3) Do not install the O-ring on this groove.

(1)

(2)

(3)

BR-00363

BR-27

Brake Booster

BRAKE

9. Brake Booster

A: REMOVAL

1) Remove or disconnect the following parts in the
engine compartment.

(1) Disconnect the connector of brake fluid level
gauge.
(2) Remove the brake pipe from the master cyl-
inder.
(3) Remove the master cylinder installation nut.
(4) Disconnect the vacuum hose from brake
booster.

2) Remove the following parts from the pedal
bracket.

(1) Snap pin and clevis pin
(2) Four brake booster installation nuts

3) Remove the brake booster while avoiding the
brake pipe.

NOTE:
• Make sure that the booster shell and vacuum
pipe are not subject to strong impacts.
• Be careful not to drop the brake booster. If the
booster is dropped, replace it.
• Use special care when handling the operating
rod. If excessive force is applied to the operating
rod, the angle may change by 

r3°, and it may result

in damage to power piston cylinder.
• Be careful when placing the brake booster on
floor.
• Do not change the push rod length.

CAUTION:
• Do not disassemble the brake booster.
• If external force is applied from above when
brake booster is placed in this position, the res-
in portion as indicated by “P” may become
damaged.

(1) Nut

(2) Clevis pin

(3) Snap pin

(4) Operating rod

(1)

(3)

(4)

(2)

BR-00073

(1) Force

(1)

P

BR-00075