Subaru Legacy III (2000-2003 year). Manual - part 849

PS-84

POWER ASSISTED SYSTEM (POWER STEERING)

OIL PUMP

5) Temporarily install rear cover to front casing.
6) Remove oil pump pulley.

7) Place oil pump in a vise.

CAUTION:
Do not place oil pump directly in the vise, use 
soft pads and hold oil pump lightly to protect 
the pump.
8) Pry oil seal off using a screwdriver.

CAUTION:
Be careful not to scratch inner surface of cas-
ing.

D: ASSEMBLY

1) Reassembly precautions

(1) Whenever O-rings, oil seals, and snap rings
are removed, they must be replaced with new
ones.
(2) Thoroughly wash parts and allow to dry.
They must be kept free from cleaning oil and
dust.
(3) Reassembly procedure must be performed
in clean place. Ensure that parts are kept away
from waste threads or other dust particles.
(4) Cleaning oil tends to stay inside the front
casing. Remove it completely by blowing com-
pressed air.
(5) Ensure that parts are free from rust. (Use
specified hydraulic oil for rust prevention after
cleaning and drying.)
(6) Reverse the sequence of disassembly pro-
cedures.

2) Apply grease to oil seal and inner surface of front
casing (at bearing location).

CAUTION:
Make sure that the front body internal surfaces 
are free from damage.
3) Temporarily install rear cover to front body.
4) Attach ST to front body. Using a press, install oil
seal.
ST

34199AE030

INSTALLER

5) Install pump pulley to front body.
6) Using ST, place oil pump in a vise.
ST

34199AE020

ATTACHMENT

7) Remove rear cover.
8) Using 10-mm box wrench, tap retaining ring into
shaft groove.

9) Install pressure plate as shown in the figure.

10) Apply specified hydraulic oil to O-rings and fit
them into front casing and pressure plate.
11) Install seal ring to pressure plate.

PS-00236

PS-00237

(1) Groove

PS-00238

ST

PS-00239

PS-00240

( 1 )

PS-85

POWER ASSISTED SYSTEM (POWER STEERING)

OIL PUMP

12) With knock pin positions aligned, install rear
cover.

Tightening torque:

27.5 N·m (2.8 kgf-m, 20.3 ft-lb)

CAUTION:
Loosely tighten bolts in the sequence (A), (B), 
(C), and (D) shown in figure. Then, tighten in the 
same sequence.

13) When reassembly procedures have been com-
pleted, turn shaft by hand to ensure it turns smooth-
ly. If it binds or other unusual conditions are
evident, disassemble again and check for foreign
matter trapped on sliding surfaces and improper in-
stallation. Eliminate the cause of trouble.
14) Check followings by referring to “CHECK” arti-
cle.
• Excessive play in pulley shaft
• Ditch deflection of pulley
• Resistance to rotation of pulley
• Measurement of generated oil pressure

PS-00241

( A )

( B )

( C )

( D )

PS-86

POWER ASSISTED SYSTEM (POWER STEERING)

OIL PUMP

E: INSPECTION

1. BASIC INSPECTION

Perform the following inspection procedures and repair or replace defective parts.

• In accordance with the following table, check all removed parts for wear and damage, and make repair or
replacement if necessary.

Part name

Description

Remedy

1. Front casing

1) Damage on body surfaces
2) Excessive wear on hole, into which spool 
valve is inserted.
3) Wear and damage on cartridge assembly 
mounting surface
4) Wear and damage on surfaces in contact with 
shaft and oil seal

Replace with a new one together with spool 
valve as selective fit is made.

2. Rear cover

1) Damage on body surfaces
2) Wear and damage on sliding surfaces

Replace with a new one.

3. Shaft

1) Shaft bend
2) Wear and damage on surfaces in contact with 
bushing and oil seal
3) Wear and damage on rotor mounting surfaces
4) Bearing damage

Replace with a new one.

4. Pressure plate

Wear and damage on sliding surfaces

Replace with a new one.

5. Cam ring

Ridge wear on sliding surfaces

If damage is serious, replace with a new car-
tridge assembly.

6. Vane

Excessive wear on nose radius and side sur-
faces

7. Rotor

1) Wear and damage on sliding surfaces
2) Ridge wear on vane sliding grooves (If light 
leaks with vane in slit against light source)

3) Damage resulting from snap ring removal

Correct with oil stone. If damage is serious, 
replace with a new cartridge assembly.

8. Connector

Damage on threads

Replace with a new one.

9. Spring

Damage

Replace with a new one.

10. Bolts and nuts

Damage on threads

Replace with a new one.

No.

Parts

Inspection

Corrective action

1

Oil pump (Exterior)

(1) Crack, damage or oil leakage

Replace oil pump with a new one.

(2) Play of pulley shaft

Measure radial play and axial play.
If any of these exceeds the service limit, replace oil 
pump with a new one. 

2

Pulley

(1) Damage

Replace it with a new one.

(2) Bend

Measure V ditch deflection.
If it exceeds the service limit, replace pulley with a 
new one.

3

Oil pump (Interior)

(1) Defect or burning of vane pump

Check resistance to rotation of pulley.
If it is past the service limit, replace oil pump with a 
new one.

(2) Bend in the shaft or damage to 
bearing

Oil pump emits a noise that is markedly different in 
tone and loudness from a sound of a new oil pump 
when turning with a string put around its pulley, 
replace oil pump with a new one.

4

O-ring

Crack or deterioration

Replace it with a new one.

5

Bracket

Crack

Replace it with a new one.

PS-87

POWER ASSISTED SYSTEM (POWER STEERING)

OIL PUMP

2. SERVICE LIMIT

Make a measurement as follows. If it exceeds the
specified service limit, replace the parts with new
ones.

CAUTION:
• Fix oil pump on a vise to make a measure-
ment. At this time, hold oil pump with the least
possible force between two wood pieces.
• Do not set outside of flow control valve or
pulley on a vise; otherwise outside or pulley
might be deformed. Select properly sized wood
pieces.
1) Play of pulley shaft

On condition:

P: 9.8 N (1.0 kgf, 2.2 lb)

Service limit:

Radial play (Direction 

)

0.4 mm (0.016 in) or less

Axial play (Direction 

)

0.6 mm (0.024 in) or less

2) Ditch deflection of pulley

Service limit:

1.0 mm (0.039 in) or less

NOTE:
Read the value for one surface of V ditch, and then
the value for another off the dial.

3) Resistance to rotation of pulley

Service limit:

Maximum load; 9.22 N (0.94 kgf, 2.07 lb) or 
less

NOTE:
• A rather higher value may be indicated when pul-
ley starts turning.
• Measure the load during rotation and make a
judgment.

(1) Dial indicator

(1) Dial indicator

PS-00145

( 1 )

P

PS-00146

( 1 )

P

(1) Dial indicator

(1) Spring balance

PS-00147

( 1 )

PS-00148

( 1 )