LEXUS SC400 1991 Service Repair Manual

4. INSPECT DRIVE AND DRIVEN ROTORS
A. Install casing and rotors to rear housingFace the dot mark of the rotors upward.
B. Inspect rotor side clearance HINT: Before measuring the clearance, remove one side of
the rotor.
Using a feeler gauge and precision straight edge, measure
the clearance between the rotor and precision straight edge.
Standard side clearance:
Drive rotor 0.02 mm (0.0008 in.)
Driven rotor 0.03 mm (0.0012 in.)
Maximum side clearance: Drive rotor 0.03 mm (0.0012 in.)
Driven rotor 0.04 mm (0.0016 in.)
If the clearance is greater than maximum, replace the rotors
as a set. If necessary, replace the housings.
C. Inspect rotor body clearance Using a feeler gauge, measure the clearance between the
driven rotor and casing.
Standard body clearance: 0.05±0.09 mm
(0.0020±0.0035 in.)
Maximum body clearance: 0.10 mm (0.0039 in.)
If the clearance is greater than maximum, replace the rotors
as a set. If necessary, replace the casing.
D. Inspect rotor tip clearance Using a feeler gauge, measure the clearance of all the six
drive rotor tips between the drive and driven rotors.
Standard tip clearance: 0.02 mm (0.0008 in.)
Maximum tip clearance: 0.03 mm (0.0012 in.)
If the clearance is greater than maximum, replace the rotors
as a set.
E. Remove rotors and causing from rear housing
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5. INSPECT OIL CLEARANCE OF DRIVE SHAFT(a) Using a caliper gauge, measure the bushing insidediameter on the housing.
Bushing inside diameter: 17.00±17.05 mm
(0.6693±0.6713 in.)
(b) Using a micrometer, measure the drive shaft diameter.
Shaft diameter: 16.97±16.98 mm(0.6681±0.6685 in.)
(c) Subtract the drive shaft diameter measurement from the
bushing inside diameter measurement.
Standard clearance: 0.02±0.08 mm
(0.0008±0.0031 in.)
Maximum clearance: 0.08 mm (0.0031 in.)
If the clearance is greater than maximum, replace the shaft.
If necessary, replace the housings.
6. INSPECT SOLENOID VALVE RESISTANCE Using an ohmmeter, measure the resistance between the ter-
minals.
Resistance (Cold): 7.5±8.5

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REPLACEMENT OF OIL SEAL
1. REMOVE OIL SEALUsing SST and a hammer, tap out the oil seal.
SST 09631±10030
2. INSTALL OIL SEAL (a) Using a 22 mm socket wrench and hammer, tap in a new
oil seal until its surface is flush with the housing edge.
(b) Apply fluid to the oil seal lip.
ASSEMBLY OF HYDRAULIC PUMP
(See Components on page CO±31)
HINT:
w Thoroughly clean all parts to be assembled.
w Before installing the parts, apply new fluid to all sliding
and rotating surfaces.
1. MOUNT REAR HOUSING HINT: Mount the parts in a vise as shown in the illustration.
2. INSTALL SPOOL VALVE (a) Align the small hole of the spool sleeve with the hole ofthe rear housing, and insert the spool body into the rear
housing.
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(b) Insert the compression spring and spool valve into therear housing.
(c) Install a new O±ring to the end plug.
(d) Apply fluid to the O±ring.
(e) Temporarily install the end plug.
(f) Insert a 5 mm (0.19 in.) straight pin through the holes of the rear housing and spool sleeve.
(g) Using a 10 mm hexagon wrench, install the end plug.
Torque: 19 N Vm (200 kgf Vcm, 14 ft Vlbf)
(h) Pull out the straight pin.
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3. REMOUNT REAR HOUSINGHINT: Mount the parts in a vise as shown in the illustration.
4. INSTALL CASING HINT: If rubber from the O±rings adheres to the O±ring instal-
lation location, replace the casing.
(a) Install a new O±ring to the rear housing groove.
(b) Align the pin hole of the casing with the straight pin onthe rear housing, and install the casing.
5. INSTALL REAR THRUST WASHER
6. INSTALL DRIVEN AND DRIVE ROTORS Install the d rive and driven rotors with the dot mark facing up-
ward.
7. INSTALL DRIVE SHAFT
8. INSTALL FRONT THRUST WASHER
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9. INSTALL FRONT HOUSING(a) Install a new O±ring to the casing groove.
(b) Align the pin holes of the front housing with the straightpin.
(c) Apply a light coat of fluid on the threads and under the heads of the mounting bolts.
(d) Install the front housing with the five bolts.
Torque: 21 N Vm (210 kgf Vcm, 15 ft Vlbf)
10. INSTALL DRIVE SHAFT PRELOAD
(a) Check that the drive shaft rotates smoothly withoutabnormal noise.
(b) Temporarily install the pulley nut, and check the rotating torque.
Rotating torque:
0.3 N Vm (3.0 kgf Vcm, 2.6 in. Vlbf)
11. INSTALL PUMP PULLEY
(a) Slide the pulley onto the drive shaft.
(b) Measure the clearance between the pulley end anddrive shaft end.
Standard: 1.3±1.7 mm (0.051±0.067 in.)
Minimum: 1.0 mm (0.039 in.)
If the clearance is less than minimum, replace the pulley.
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(c) Using SST, install the pulley with the nut. Tighten the nut
by turning it counterclockwise.
SST 09278±54012
Torque: 59 N Vm (600 kgf Vcm, 43 ft Vlbf)
12. INSTALL SOLENOID VALVE
(a) Install a new O±ring to the solenoid valve.
(b) Install a new O±ring to the rear housing groove.
(c) Apply fluid to the two O±rings.
(d) Install the solenoid valve.
Torque: 39 N Vm (400 kgf Vcm, 28 ft Vlbf)
13. INSTALL WIRE CLAMP
(a) Install the wire clamp to the read wire.
(b) Install the wire clamp to the rear housing.
14. INSTALL SUCTION PORT UNION (a) Install the O±ring to the port union.
(b) Apply fluid to the O±ring.
(c) Install the port union with the bolt.
Torque: 13 N Vm (135 kgf Vcm, 10 ft Vlbf)
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INSTALLATION OF HYDRAULIC PUMP
(See Components on page CO±26)
1. INSTALL HYDRAULIC PUMP (a) Install the hydraulic pump, solenoid valve connector
clamp and engine speed sensor wire clamp with the two
bolts and two nuts.
Torque:
12 mm head 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
14 mm head 20 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Each bolt length is indicated in the illustration.
Bolt length:
A 106 mm (4.17 in.) for 12 mm head
B 114 mm (4.49 in.) for 14 mm head
(b) Connect the solenoid valve connector.
2. CONNECT PRESSURE AND SUCTION HOSES TO HYDRAULIC PUMP
(a) Connect the pressure hose with new gasket and unionbolt.
Torque: 64 N Vm (650 kgf Vcm, 47 ft Vlbf)
(b) Connect suction hose.
3. INSTALL RH NO.2 TIMING BELT COVER
(a) Install the four gaskets to the timing belt cover.
(b) Install the connector grommet to the timing belt cover.
(c) Install the timing belt cover with the five bolts.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
HINT (12 mm head bolt): Use bolts 106 mm (4.17 in.) in
length.
(d) Install the wire clamp to the timing belt cover.
(e) Install the cam position sensor wire to the wire clamp on
the timing belt cover.
(f) Install the cam position sensor connector to the ignition coil bracket.
4. INSTALL LH NO.2 TIMING BELT COVER (a) Install the two gaskets to the timing belt cover.
(b) Run the cam po sition sensor wire through the timing belt
cover hole.
(c) Install the timing belt cover and connector bracket with the three bolts.
(d) Connect the cam position sensor connector.
(e) In sta ll th e ca m po sitio n se n so r c onnector to the
connector bracket.
(f) Install the cam position sensor wire to the wire clamp on
the timing belt cover.
(g) Install the connector grommet to the timing belt cover.
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5. INSTALL DRIVE BELT IDLER PULLEYInstall the idler pulley and cover plate with the pulley bolt.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
6. CONNECT RADIATOR HOSE TO WATER INLET
7. INSTALL RH NO.3 TIMING BELT COVER
(a) Install the three gaskets to the timing belt cover.
(b) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(c) Install the timing belt cover with the three bolts.
8. INSTALL VSV FOR EVAP SYSTEM Install the VSV with the two bolts.
9. INSTALL LH NO.3 TIMING BELT COVER (a) Install the three gaskets to the timing belt cover.
(b) Install the cord grommet to the high±tension cord.
(c) Install the cord grommet to the timing belt cover.
(d) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(e) Install the timing belt cover with the four bolts.
10. INSTALL RH ENGINE WIRE COVER (a) Fit portions A and B of the engine wire cover, matchingthem with the lower high±tension cord cover and No.3
timing belt cover.
(d) Install the engine wire cover with the bolt.
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11. INSTALL LH ENGINE WIRE COVER(a) Connect portions A and B engine wire cover to the wirebrackets.
(b) Set the VSV (for fuel pressure control system) wire in
original position.
(c) Fit portions C and D of the engine wire cover, matching them with the lower high±tension cord cover and No.3
timing belt cover.
(d) Install the engine wire cover with the two bolts.
12. INSTALL UPPER HIGH±TENSION CORD COVER (a) Fit portion A of the upper high±tension cover, matchingit with the top of the lower high±tension cord cover.
(b) Push the front side of the high±tension cord cover, and connect the front side claw groove of the upper
high±tension cord cover to the claw of the lower
high±tension cord cover.
(c) Install the upper high±tension cord cover with the two bolts.
13. INSTALL INTAKE AIR CONNECTOR (a) Connect the end portions of the intake air connector tothe throttle body and air cleaner hose.
(b) Tighten the two hose clamps.
(c) Install the bolt holding the intake air connector to the cylinder head cover.
(d) Connect the following hoses: (1) Air hose to ISC valve
(2) Air hose (from PS air control valve) to intake air con- nector
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