1996 SUBARU LEGACY brake fluid

6. Brake Booster
A: REMOVAL
1) Remove or disconnect the following parts at engine
compartment.
(1) Disconnect connector for brake fluid level indicator.
(2) Remove brake pipes from master cylinder.
(3) Remove master cylinder installing nuts.
(4) Disconnect vacuum hose from brake booster.
2) Remove the following parts from the pedal bracket.
(1) Snap pin and clevis pin
(2) Four brake booster installing nuts
3) Remove brake booster while shunning brake pipes.
B4M0117A
B: INSTALLATION
1) Mount brake booster in position.
2) Connect operating rod to brake pedal with clevis pin
and snap pin.

1Clevis pin

2Snap pin

3Operating rod
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3) Connect vacuum hose to brake booster.
4) Mount master cylinder onto brake booster.
5) Connect brake pipes to master cylinder.
6) Connect electric connector for brake fluid level indica-
tor.
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4-4SERVICE PROCEDURE
6. Brake Booster

8. LACK OF BOOSTING ACTION CHECK
Turn off engine, and set the vacuum gauge reading at“0”.
Then, check the fluid pressure when brake pedal is
depressed. The pressure must be greater than the stan-
dard value listed below.
Brake pedal force 147N (15 kg, 33 lb) 294N (30kg, 66 lb)
Models without ABS and
TCS785 kPa
(8 kg/cm
2, 114 psi)2,158 kPa
(22 kg/cm2, 313 psi)
Models with ABS and
TCS588 kPa
(6 kg/cm
2, 85 psi)1,667 kPa
(17 kg/cm2, 242 psi)
9. BOOSTING ACTION CHECK
Set the vacuum gauge reading at 66.7 kPa (500 mmHg,
19.69 inHg) by running engine. Then, check the fluid pres-
sure when brake pedal is depressed. The pressure must
be greater than the standard value listed below.
Brake pedal force 147N (15 kg, 33 lb) 294N (30kg, 66 lb)
Models without ABS and
TCS5,492 kPa
(56 kg/cm
2, 796 psi)8,434 kPa
(86 kg/cm2, 1,223 psi)
Models with ABS and
TCS5,394 kPa
(55 kg/cm
2,782 psi)10,003 kPa
(102 kg/cm2, 1,450
psi)
D: HANDLING PRECAUTIONS
1) Be careful not to drop brake booster. Brake booster
should be discarded if it has been dropped.
2) Use special care when handling operating rod.
If excessive force is applied to operating rod, sufficient to
cause a change in the angle in excess of ±3°, it may result
in damage to the power piston cylinder.
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4-4SERVICE PROCEDURE
6. Brake Booster

G4M0428
8. Hill Holder
A: REMOVAL
1) Drain brake fluid from reservoir of master cylinder.
2) Remove adjusting nut and cable clamp, and disconnect
PHV cable from cable bracket on engine.
3) Detach PHV cable from clips.
4) Remove cable clamp, and disconnect PHV cable from
PHV stay.
CAUTION:
Carefully protect boots and inner cable from damage
when disconnecting PHV cable.
5) Disconnect brake pipes from PHV.
CAUTION:

Pay attention not to drop brake fluid onto body
painting since it may dissolve paint.

Pay attention not to damage hexagonal head of flare
nut by using pipe wrench without fail.
6) Detach PHV along with support from side frame.
CAUTION:
Exercise utmost care to prevent foreign matter from
entering into PHV when removing it.
B: INSPECTION
Check up removed parts as follows, and replace defective
ones.
1) Check if boots of PHV cable are damaged or degraded,
and if inner cable is damaged or corroded.
2) Check if return spring is worn out, damaged or cor-
roded.
3) Confirm that rolling sound of ball is heard with PHV
inclined and lever rotates smoothly.
CAUTION:
Never disassemble PHV. Replace entire PHV assembly
if necessary.
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4-4SERVICE PROCEDURE
8. Hill Holder

11. Air Bleeding (Without TCS model)
A: GENERAL RULES FOR EFFECTIVE
BLEEDING
1) Start with the brakes (wheels) connecting to the sec-
ondary chamber of the master cylinder.
2) The time interval between two brake pedal operations
(from the time when the pedal is released to the time when
it is depressed another time) shall be approximately 3 sec-
onds.
3) The air bleeder on each brake shall be released for 1
to 2 seconds.
B: BLEEDING PROCEDURE
CAUTION:

The FMVSS No. 116, fresh DOT3 or 4 brake fluid
must be used.

Cover bleeder with waste cloth, when loosening it,
to prevent brake fluid from being splashed over sur-
rounding parts.

Avoid mixing different brands of brake fluid to pre-
vent degrading the quality of the fluid.

Be careful not to allow dirt or dust to get into the
reservoir tank.
NOTE:

During bleeding operation, keep the brake reserve tank
filled with brake fluid to eliminate entry of air.

Brake pedal operating must be very slow.

For convenience and safety, it is advisable to have two
man working.
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1) Make sure that there is no leak from joints and connec-
tions of the brake system.
2) Fit one end of vinyl tube into the air bleeder and put the
other end into a brake fluid container.
3) Slowly depress the brake pedal and keep it depressed.
Then, open the air bleeder to discharge air together with
the fluid.
Release air bleeder for 1 to 2 seconds.
Next, with the bleeder closed, slowly release the brake
pedal.
Repeat these steps until there are no more air bubbles in
the vinyl tube.
Allow 3 to 4 seconds between two brake pedal operations.
CAUTION:
Cover bleeder with waste cloth, when loosening it, to
prevent brake fluid from being splashed over sur-
rounding parts.
NOTE:
Brake pedal operating must be very slow.
4) Tighten air bleeder securely when no air bubbles are
visible.
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4-4SERVICE PROCEDURE
11. Air Bleeding (Without TCS model)

Air bleeder tightening torque:
8±1 N⋅m (0.8±0.1 kg-m, 5.8±0.7 ft-lb)
5) Perform these steps for the brakes connecting to the
secondary chamber of master cylinder, first, and then for
the ones connecting to primary chamber. With all proce-
dures completed, fully depress the brake pedal and keep
it in that position for approximately 20 seconds to make
sure that there is no leak evident in the entire system.
G4M0436
6) Perform sequence control. (With ABS model) 4-4 [W15C1].>
7) Check the pedal stroke.
While the engine is idling, depress the brake pedal with a
490 N (50 kg, 110 lb) load and measure the distance
between the brake pedal and steering wheel. With the
brake pedal released, measure the distance between the
pedal and steering wheel again. The difference between
the two measurements must be more than specified.
Specified pedal stroke:
Without ABS
90 mm (3.54 in)
With ABS
95 mm (3.74 in)
When depressing brake pedal with a 490 N (50 kg,
110 lb) load.
(1) Models without ABS
If the distance is more than specifications, there is a
possibility that air is in the brake line. Bleed air from the
brake line.
(2) Models with ABS
If the distance is more than specifications, there is a
possibility air is in the inside of the hydraulic unit.
Therefore, air must be bled from the inside of the
hydraulic unit to the brake pipes in accordance with the
bleeding sequence control.
8) Add brake fluid to the required level (MAX. level) of
reserve tank.
9) As a final step, test run the vehicle at low speed and
apply brakes relatively hard 2 to 3 times to ensure that
brakes provide normal braking action on all four wheels
without dragging and uneven braking.
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4-4SERVICE PROCEDURE
11. Air Bleeding (Without TCS model)

12. Brake Fluid Replacement
NOTE:
To always maintain the brake fluid characteristics, replace
the brake fluid according to maintenance schedule or ear-
lier than that when used in severe condition.
A: REPLACEMENT
CAUTION:

The FMVSS No. 116, fresh DOT3 or 4 brake fluid
must be used.

Cover bleeder with waste cloth, when loosening it,
to prevent brake fluid from being splashed over sur-
rounding parts.

Avoid mixing different brands of brake fluid to pre-
vent degrading the quality of the fluid.

Be careful not to allow dirt or dust to get into the
reservoir tank.
NOTE:

During bleeding operation, keep the brake reserve tank
filled with brake fluid to eliminate entry of air.

Brake pedal operating must be very slow.

For convenience and safety, it is advisable to have two
man working.

The amount of brake fluid required is approximately 500
m
(16.9 US fl oz, 17.6 Imp fl oz) for total brake system.
1) Either jack-up vehicle and place a safety stand under it,
or lift-up vehicle.
2) Remove both front and rear wheels.
3) Draw out the brake fluid from reserve tank with syringe.
4) Refill reservoir tank with recommended brake fluid.
Recommended brake fluid:
FMVSS No. 116, fresh DOT3 or 4 brake fluid
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4-4SERVICE PROCEDURE
12. Brake Fluid Replacement

G4M0434
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G4M0435
5) Install one end of a vinyl tube onto the air bleeder of and
insert the other end of the tube into a container to collect
the brake fluid.
6) Instruct your co-worker to depress the brake pedal
slowly two or three times and then hold it depressed.
7) Loosen bleeder screw approximately 1/4 turn until a
small amount of brake fluid drains into container, and then
quickly tighten screw.
8) Repeat steps 6) and 7) above until there are no air
bubbles in drained brake fluid and new fluid flows through
vinyl tube.
CAUTION:
Add brake fluid as necessary while performing the air
bleed operation, in order to prevent the tank from run-
ning short of brake fluid.
9) After completing the bleeding operation, hold brake
pedal depressed and tighten screw and install bleeder cap.
Tightening torque (Bleeder screw):
8±1 N⋅m (0.8±0.1 kg-m, 5.8±0.7 ft-lb)
10) Bleed air from each wheel cylinder using the same
procedures as described in steps 6) through 7) above.
11) Depress brake pedal with a force of approximately 294
N (30 kg, 66 lb) and hold it there for approximately 20 sec-
onds. At this time check pedal to see if it shows any
unusual movement.
Visually inspect bleeder screws and brake pipe joints to
make sure that there is no fluid leakage.
12) Install wheels, and drive vehicle for a short distance
between 2 to 3 km (1 to 2 miles) to make sure that brakes
are operating properly.
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4-4SERVICE PROCEDURE
12. Brake Fluid Replacement

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13. Proportioning Valve
G4M0668
G4M0915
A: INSPECTION
1) Install the oil pressure gauges to measure the master
cylinder fluid pressure (front wheel brake fluid pressure)
and rear wheel cylinder fluid pressure.
2) Bleed air from the oil pressure gauges.
3) Check the master cylinder fluid pressure and rear wheel
cylinder fluid pressure.
The standard values are shown in Figure.
4) For the oil pressure in case of split point, refer to A:
SPECIFICATIONS 4-4 [S0A0].
B: REMOVAL
1) Remove brake pipe from proportioning valve at four
places.
2) Remove proportioning valve from its bracket.
CAUTION:
Do not disassemble or adjust the proportioning valve.
(The proportioning valve must be replaced as an
assembly.)
C: INSTALLATION
1) Install proportioning valve to bracket.
2) Connect brake pipes correctly to proportioning valve.
3) Bleed air, then check each joint of brake pipe for oil
leaks.
Tightening torque:
Proportioning valve to brake pipe flare nut:
15
+3
2N⋅m (1.5+0.3
0.2kg-m, 10.8+2.2
1.4ft-lb)
Proportioning valve to bracket:
18±5 N⋅m (1.8±0.5 kg-m, 13.0±3.6 ft-lb)
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4-4SERVICE PROCEDURE
13. Proportioning Valve