ignition LEXUS SC300 1991 Service Repair Manual
[x] Cancel search | Manufacturer: LEXUS, Model Year: 1991, Model line: SC300, Model: LEXUS SC300 1991Pages: 4087, PDF Size: 75.75 MB
Page 2794 of 4087

WATER PUMP
COMPONENTS FOR REMOVAL AND
INSTALLATION
REMOVAL OF WATER PUMP
1. REMOVE TIMING BELT(See steps 1 to 35 on pages EM±35 to 43)
2. REMOVE RH IGNITION COIL (a) Disconnect the ignition coil connector.
(b) Remove the two bolts and ignition coil.
3. REMOVE WATER INLET AND INLET HOUSING (a) Disconnect the water by±pass hose from the water inlethousing.
CO±8
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COOLIING SYSTEM Water Pump
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Page 2797 of 4087

(b) Apply seal packing to the sealing groove of the waterinlet housing as shown in the illustration.
Seal packing: Part No. 08826±00100 or equivalent
w Install a nozzle that has been cut to a 2±3 mm
(0.08±0.12 in.) opening.
HINT: Avoid applying an excessive amount to the surface. w Parts must be assembled within 5 minutes of
application. Otherwise the material must be
removed and reapplied.
w Immediately remove nozzle from the tube and
reinstall cap.
(c) Install a new O±ring to the water inlet housing.
(d) Apply soapy water to the O±ring.
(e) Push the water inlet housing end into water pump hole.
(f) Install the water inlet and inlet housing assembly with the two bolts. alternately tighten the bolts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolts 25 mm (0.98 in.) in length.
(g) Connect the water by±pass hose to the water inlet
housing.
3. INSTALL RH IGNITION COIL (a) Install the ignition coil with the two bolts.
(b) Connect the ignition coil connector.
4. INSTALL TIMING BELT (See steps 4 to 43 on pages EM±47 to 57)
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COOLIING SYSTEM Water PumpCO±11
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Page 2802 of 4087

REMOVAL OF RADIATOR
(See Components on page CO±15)
1. REMOVE BATTERY CAUTION: Work must be started after approx. 20 seconds or
longer from the time the ignition switch is turned to the
ºLOCKº position and the negative (±) terminal cable is dis-
connected from the battery.
2. REMOVE ENGINE UNDER COVERS
3. DRAIN ENGINE COOLANT (See page CO±6)
4. REMOVE RADIATOR RESERVOIR TANK (a) Disconnect the coolant level sensor connector.
(b) Disconnect the following hoses:(1) Reservoir hose from water inlet housing
(2) Reservoir hose from radiator
(c) Remove the two bolts and reservoir tank bracket.
(d) Disconnect the reservoir tank from the reservoir tank bracket, and remove the reservoir tank.
5. DISCONNECT HOSES Disconnect the following hoses:(1) Upper radiator hose from radiator
(2) Lower radiator hose from radiator
(3) Two oil cooler hoses (for A/T) from radiator. Plug hose end.
CO±16
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COOLIING SYSTEM Radiator
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Page 2813 of 4087

REMOVAL OF HYDRAULIC PUMP
(See Components on page CO±26)
1. REMOVE BATTERY CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE ENGINE UNDER COVER
3. DRAIN ENGINE COOLANT (See page CO±6)
4. REMOVE DRIVE BELT Loosen the drive belt tension by turning the drive belt tension-
er counterclockwise, and remove the drive belt.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
5. DISCONNECT A/C COMPRESSOR (a) Disconnect the A/C compressor connector.
(b) Remove the nut, and disconnect the ground cable.
(c) Remove the bolt and A/C compressor stay.
(d) R e m o v e t h e t w o b o l t s , a n d d i s c onnect the A/C
compressor from the engine.
6. REMOVE LH IGNITION COIL (a) Disconnect the following connectors and cord:(1) Ignition coil connector
(2) Noise filter connector
(3) High±tension cord
±
COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)CO±27
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Page 2814 of 4087

(b) Remove the two bolts and ignition coil.
7. REMOVE INTAKE AIR CONNECTOR (a) Disconnect the following hoses:(1) Air hose from ISC valve
(2) Air hose (from PS air control valve) from intake air
connector
(b) Remove the bolt holding the intake air connector to the cylinder head cover.
(c) Loosen the two hose clamps.
(d) Disconnect the intake air connector from the throttle
body and air cleaner hose, and remove the throttle body.
8. REMOVE UPPER HIGH±TENSION CORD COVER (a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord coverfrom the claw of the lower cover, and remove the cord
cover.
9. REMOVE RH ENGINE WIRE COVER Remove the bolt and engine wire cover.
CO±28
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COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)
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Page 2816 of 4087

15. REMOVE RH NO.2 TIMING BELT COVER(a) Disconnect the cam position sensor connector from theignition coil bracket.
(b) Disconnect the cam position sensor wire from the clamp
on the timing belt cover.
(c) Remove the five mounting bolts.
(d) Disconnect the wire clamp from the timing belt cover,
and remove the timing belt cover and four gasket.
16. REMOVE LH NO.2 TIMING BELT COVER (a) Disconnect the cam position sensor wire from the clamp
on the timing belt cover.
(b) Disconnect the cam position sensor connector.
(c) Remove the three mounting bolts.
(d) Disconnect the connector grommet from the timing belt cover, and remove the timing belt cover and two
gaskets.
17. DISCONNECT PRESSURE AND SUCTION HOSES FROM HYDRAULIC PUMP
18. REMOVE HYDRAULIC PUMP (a) Disconnect the solenoid valve connector.
(b) Remove the two mounting bolts and two nuts.
(c) Disconnect the engine speed sensor wire clamp.
(d) Remove the hydraulic pump.
CO±30
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COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)
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Page 2828 of 4087

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.
CO±42
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COOLIING SYSTEM Electronically Controlled Hydraulic Cooling Fan
(Hydraulic Pump)
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Page 2831 of 4087

14. INSTALL IGNITION COIL(a) Install the ignition coil with the two bolts.
(b) Connect the following connectors and cord:(1) Ignition coil connector
(2) Noise filter connector
(3) High±tension cord
15. INSTALL A/C COMPRESSOR (a) In sta ll th e A/C co mp re sso r, co mp re sso r sta y an dground cable with the three bolts and nut.
Torque: Bolt 49 N Vm (500 kgf Vcm, 36 ft Vlbf)
Nut 29 N Vm (300 kgf Vcm, 22 ft Vlbf)
(b) Connect the A/C compressor connector.
16. INSTALL DRIVE BELT Install the drive belt by turning the drive belt tensioner coun-
terclockwise.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
17. CONNECT RADIATOR HOSE TO WATER INLET
±
COOLIING SYSTEM Electronically Controlled Hydraulic Cooling Fan
(Hydraulic Pump)CO±45
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Page 2834 of 4087

REMOVAL OF HYDRAULIC MOTOR
(See Components on page CO±47)
1. REMOVE BATTERY CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE ENGINE UNDER COVERS
3. DRAIN ENGINE COOLANT (See page CO±6)
4. REMOVE RADIATOR RESERVOIR TANK (a) Disconnect the coolant level sensor connector.
(b) Disconnect the following hoses:(1) Reservoir hose from water inlet housing
(2) Reservoir hose from radiator
(c) Remove the two bolts and reservoir tank bracket.
(d) Disconnect the reservoir tank from the reservoir tank bracket, and remove the reservoir tank.
5. DISCONNECT HOSES Disconnect the following hoses:(1) Upper radiator hose from radiator
(2) Pressure hose from hydraulic motor
(3) Return hose from hydraulic motor
CO±48
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COOLIING SYSTEM Electronically Controlled Hydraulic Cooling Fan
(Hydraulic Motor)
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Page 2847 of 4087

INSPECTION OF COOLING FAN ECU
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OFBATTERY
CAUTION: Work must be started after 20 seconds or longer
from the time the ignition switch is turned to the ºLOCKº posi-
tion and the negative (±) terminal cable is disconnected from
the battery.
2. DISCONNECT COOLING FAN ECU CONNECTOR (See Components on page CO±60)
(a) Remove the instrument panel under cover.
(b) Remove the lower instrument panel finish panel and glove compartment door assembly.
(c) Disconnect the cooling fan ECU connector.
3. INSPECT COOLING FAN ECU (a) Connect the cable to the negative (±) terminal of thebattery.
(b) Check the connector on the wiring harness side as shown in the chart.
Check forTester connectionConditionSpecified value
Voltage1±GroundIgnition switch ONBattery voltage
Resistance2±3Solenoid valve at cold (20 5C (68 5F))7.5±8.5
Continuity4±Ground±Continuity
Continuity5±GroundThrottle valve openNo continuityContinuity5±GroundThrottle valve closedContinuity
Resistance9±10Coolant temp. at 80 5C (176 5F)1.48±1.58 k
(c) Disconnect the cable from the negative (±) terminal of
the battery.
4. RECONNECT COOLING FAN ECU CONNECTOR
5. RECONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
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COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Electronic Control Parts)CO±61
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