SUBARU LEGACY 1997 Service Repair Manual

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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12. Brake Fluid Replacement

G4M0434
G4M0438
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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12. Brake Fluid Replacement

B4M1177A
13. Proportioning Valve
B4M1197A
B4M1198A
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 [S1A0].
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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13. Proportioning Valve

14. ABS Sensor
A: REMOVAL
1. FRONT ABS SENSOR
1) Disconnect front ABS sensor connector located in
engine compartment.
B4M0079A
2) Remove bolts which secure sensor harness to strut.
G4M0451
3) Remove bolts which secure sensor harness to body.
G4M0443
4) Remove bolts which secure front ABS sensor to
housing, and remove front ABS sensor.
CAUTION:

Be careful not to damage pole piece located at tip of
the sensor and teeth faces during removal.

Do not pull sensor harness during removal.
5) Remove front disc brake caliper and disc rotor from
housing after removing front tire.
6) Remove front drive shaft and housing and hub assem-
bly. <Ref. to 4-2 [W1A0].>
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4-4SERVICE PROCEDURE
14. ABS Sensor

G4M0444
7) Remove tone wheel while removing hub from housing
and hub assembly. <Ref. to 4-2 [W1B0].>
CAUTION:
Be careful not to damage teeth faces of tone wheel
during removal.
2. REAR ABS SENSOR
1) Remove rear seat and disconnect rear ABS sensor con-
nector.
2) Remove rear sensor harness bracket from rear trailing
link and bracket.
G4M0445
3) Remove rear ABS sensor from rear back plate.
4) Remove rear tone wheel while removing hub from
housing and hub assembly. <Ref. to 4-2 [W2A0].>
CAUTION:

Be careful not to damage pole piece located at tip of
the sensor and teeth faces during removal.

Do not pull sensor harness during removal.
B: INSPECTION
1. ABS SENSOR
1) Check pole piece of ABS sensor for foreign particles or
damage. If necessary, clean pole piece or replace ABS
sensor.
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14. ABS Sensor

B4M0248
2) Measure ABS sensor resistance.
ABS sensor Terminal No. Standard
Front - LH 1 and 2
1.0±0.2 kΩ Front - RH 1 and 2
Rear - LH 1 and 2
Rear - RH 1 and 2
CAUTION:
If resistance is outside the standard value, replace
ABS sensor with new one.
NOTE:
Check ABS sensor cable for discontinuity. If necessary,
replace with a new one.
G4M0448
2. TONE WHEEL
1) Check tone wheel’s teeth (44 pieces) for cracks or
dents. If necessary, replace tone wheel with a new one.
2) Clearances (sensor gaps) should be measured one by
one to ensure tone wheel and speed sensor are installed
correctly.
ABS sensor clearance:
Front
0.9—1.4 mm (0.035—0.055 in)
Rear
0.7—1.2 mm (0.028—0.047 in)
NOTE:

If clearance is narrow, adjust by using spacer (Part No.
26755AA000).

If clearance is wide, check the outputted voltage then
replace ABS sensor or tone wheel if the outputted voltage
is outside the specification.
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4-4SERVICE PROCEDURE
14. ABS Sensor

B4M0118B
3. OUTPUT VOLTAGE
Output voltage can be checked by the following method.
Install resistor and condenser, then rotate wheel about 2.75
km/h (2 MPH) or equivalent.
NOTE:
Regarding terminal No., please refer to item 1. ABS SEN-
SOR.
C: INSTALLATION
1. FRONT ABS SENSOR
1) Install tone wheel on hub, then install housing on hub
assembly. <Ref. to 4-2 [W1D0].>
G4M0443
2) Temporarily install front ABS sensor on housing.
CAUTION:
Be careful not to strike ABS sensor’s pole piece and
tone wheel’s teeth against adjacent metal parts during
installation.
3) Install front drive shaft to hub spline. <Ref. to 4-2
[W1E0].>
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4-4SERVICE PROCEDURE
14. ABS Sensor

G4M0451
4) Install front ABS sensor on strut and wheel apron
bracket.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
5) Place a thickness gauge between ABS sensor’s pole
piece and tone wheel’s tooth face. After standard clearance
is obtained over the entire perimeter, tighten ABS sensor
on housing to specified torque.
ABS sensor standard clearance:
0.9—1.4 mm (0.035—0.055 in)
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
CAUTION:
Check the marks on the harness to make sure that no
distortion exists. (RH: white, LH: yellow)
NOTE:
If the clearance is outside specifications, readjust.
2. REAR ABS SENSOR
1) Install rear tone wheel on hub, then rear housing on
hub. <Ref. to 4-2 [W2D0].>
G4M0445
2) Temporarily install rear ABS sensor on back plate.
CAUTION:
Be careful not to strike ABS sensor’s pole piece and
tone wheel’s teeth against adjacent metal parts during
installation.
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4-4SERVICE PROCEDURE
14. ABS Sensor

3) Install rear drive shaft to rear housing and rear differen-
tial spindle. <Ref. to 4-2 [W2E0].>
G4M0453
4) Install rear sensor harness on rear trailing link.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
5) Place a thickness gauge between ABS sensor’s pole
piece and tone wheel’s tooth face. After standard clearance
is obtained over the entire perimeter, tighten ABS sensor
on back plate to specified torque.
ABS sensor standard clearance:
0.7—1.2 mm (0.028—0.047 in)
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
CAUTION:
Check the marks on the harness to make sure that no
distortion exists. (RH: white, LH: yellow)
NOTE:
If the clearance is outside specifications, readjust.
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4-4SERVICE PROCEDURE
14. ABS Sensor

15. Hydraulic Unit for ABS System
(ABS 5.3 Type)
B4M0994A
1Hydraulic control unit

2Damper

3Stud bolt

4Rear-RH outlet

5Rear-LH outlet

6Secondary inlet

7Primary inlet
8Front-LH outlet

9Front-RH outlet

10Cable clip

11Bracket

12Relay box

13Motor relay

14Valve relay
15Cap

16Connector bracket
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 18±5 (1.8±0.5, 13.0±3.6)
T2: 29±7 (3.0±0.7, 21.7±5.1)
T3: 32±10 (3.3±1.0, 24±7)
A: REMOVAL
1. HYDRAULIC UNIT
1) Disconnect ground cable from battery.
2) Remove air intake duct and canister from engine com-
partment to facilitate removal of hydraulic unit.
3) Disconnect connector from hydraulic unit.
4) Unlock cable clip.
5) Disconnect brake pipes from hydraulic unit.
CAUTION:
Wrap brake pipes with vinyl bag to avoid spilling brake
fluid on vehicle body.
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15. Hydraulic Unit for ABS System (ABS 5.3 Type)