cooling LEXUS GS400 2000 Service User Guide

AC0Y2±01
I03743
1 2 AC±80
± AIR CONDITIONINGCONDENSER FAN
2765 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CONDENSER FAN
ON±VEHICLE INSPECTION
1. INSPECT CONDENSER FAN OPERATION
Inspect the fan operation, as shown in the chart below.
Test conditions:

Ignition switch ON

Blower speed control switch position ºHIº

Temperature control dial at ºMAX. COOLº

Install manifold gauge setº

A/C switch ON
ConditionFan operation (Fan speed)
Engine coolant temperature
91°C (196 °F) or belowRotate (Low speed)
Engine coolant temperature
100°C (212 °F) or aboveRotate (High speed)
Refrigerant pressure is less than
1,520 kPa (15.5 kgf´cm2, 220 psi)Rotate (Low speed)
Refrigerant pressure is 1,520 kPa
(15.5 kgf´cm2, 220 psi) or aboveRotate (High speed)
If operation is not as specified, proceed to the next inspection.
2. INSPECT CONDENSER FAN MOTOR OPERATION
(a) Disconnect the fan connector.
(b) Connect the positive (+) lead from the battery to terminal
2 and negative (±) lead to terminal 1 then check that motor
operations smoothly.

If operation is not as specified, replace the fan mo-
tor.

If operation is as specified, check the pressure
switch, cooling fan relays and engine coolant temp.
switch.

AC0Y3±01
I04719
Air Cleaner AssemblyRadiator Reservoir
Tank Cap
Cooling Fan Assembly
Air Cleaner
DuctUpper Radiator Hose
Reservoir Hose
Fan Motor
Fan Motor
Fan Shroud
Fan
Fan
± AIR CONDITIONINGCONDENSER FAN
AC±81
2766 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPONENTS

AC0Y4±01
AC±82
± AIR CONDITIONINGCONDENSER FAN
2767 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. DRAIN ENGINE COOLANT FROM RADIATOR
HINT:
It is not necessary to drain out all coolant.
2. REMOVE THESE PARTS:
(a) Air cleaner duct
(b) Air cleaner assembly
(c) Radiator reservoir tank cap
3. DISCONNECT THESE PARTS:
(a) Upper radiator hose
(b) Reservoir hose
4. REMOVE COOLING FAN
(a) Disconnect the connectors.
(b) Remove the 6 bolts cooling fan.

AC0Y5±01
± AIR CONDITIONINGCONDENSER FAN
AC±83
2768 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DISASSEMBLY
1. REMOVE COOLING FANS
Remove the 2 nuts and both fans.
2. REMOVE COOLING FAN MOTORS
(a) Disconnect wire harness clamps.
(b) Remove the 6 screws and both motors.

D01047
Q03721
D01048
Q06925
AT±30
± AUTOMATIC TRANSMISSIONAUTOMATIC TRANSMISSION UNIT (2JZ±GE)
1978 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
12. REMOVE TORQUE CONVERTER CLUTCH MOUNT-
ING BOLT
(a) Remove the hole plug.
(b) Turn the crankshaft to gain access to each bolt.
(c) Hold the crankshaft pulley nut with a wrench and remove
the 6 bolts.
Torque: 48 N´m (490 kgf´cm, 35 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
First install black colored bolt and then the 5 other bolts.
13. SUPPORT TRANSMISSION WITH JACK
14. REMOVE 4 ENGINE REAR MOUNTING SET BOLTS
Torque: 26 N´m (270 kgf´cm, 20 ft´lbf)
15. DISCONNECT CONNECTORS AND WIRE HARNESS
(a) Tilt down the transmission.
NOTICE:
Take care so that the cooling fan does not come in contact
with the fan shroud.
(b) Disconnect the following connectors:
(1) O/D direct clutch speed sensor connector
(2) Vehicle speed sensor connector
(3) Park/neutral position switch connector
(4) Solenoid connector
(c) Disconnect the wire harness from the clamp on the trans-
mission.

D01005
Q03721
D01048
Q06925
AT±36
± AUTOMATIC TRANSMISSIONAUTOMATIC TRANSMISSION UNIT (1UZ±FE)
1984 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Turn the crankshaft to gain access to each bolt.
(c) Hold the crankshaft pulley nut with a wrench and remove
the 6 bolts.
Torque: 48 N´m (490 kgf´cm, 35 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
First install the black colored bolt and then the 5 other bolts.
12. SUPPORT TRANSMISSION WITH JACK
13. REMOVE 4 ENGINE REAR MOUNTING SET BOLTS
Torque: 26 N´m (270 kgf´cm, 20 ft´lbf)
14. DISCONNECT CONNECTORS AND WIRE HARNESS
(a) Tilt down the transmission.
NOTICE:
Take care so that the cooling fan does not come in contact
with the fan shroud.
(b) Disconnect the following connectors:
(1) O/D direct clutch speed sensor connector
(2) Vehicle speed sensor connector
(3) Park/neutral position switch connector
(4) Solenoid connector
(c) Disconnect the wire harness from the clamp on the trans-
mission.

CO09W±03
± COOLING (2JZ±GE)COOLANT
CO±1
1539 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COOLANT
INSPECTION
1. CHECK ENGINE COOLANT LEVEL AT RESERVOIR
The engine coolant level should be between the ºLOWº and ºFULLº lines, when the engine is cold.
If low, check for leaks and add ºToyota Long Life Coolantº or equivalent up to the ºFULLº line.
2. CHECK ENGINE COOLANT QUALITY
There should not be any excessive deposits of rust or scale around the radiator cap or radiator filler hole,
and the coolant should be free from oil.
If excessively dirty, replace the coolant.

CO0A2±03
B01987
Thermostat

Gasket Water Inlet

Non±reusable part
CO±10
± COOLING (2JZ±GE)THERMOSTAT
1548 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
THERMOSTAT
COMPONENTS

CO0A3±01
B01940
± COOLING (2JZ±GE)THERMOSTAT
CO±11
1549 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
HINT:
Removal of the thermostat would have an adverse effect, caus-
ing a lowering of cooling efficiency. Do not remove the thermo-
stat, even if the engine tends to overheat.
1. DRAIN ENGINE COOLANT
2. DISCONNECT WATER INLET FROM WATER PUMP,
AND REMOVE THERMOSTAT
(a) Remove the 2 nuts holding the water inlet to the water
pump, and disconnect the water inlet from the water
pump.
(b) Remove the thermostat.
(c) Remove the gasket from the thermostat.

CO0A4±01
P 1111 6
CO0601
P03242
Valve
Lift CO±12
± COOLING (2JZ±GE)THERMOSTAT
1550 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
INSPECT THERMOSTAT
HINT:
The thermostat is numbered with the valve opening tempera-
ture.
(a) Immerse the thermostat in water and gradually heat the
water.
(b) Check the valve opening temperature.
Valve opening temperature: 80 ± 84°C (176 ± 183°F)
If the valve lift is not as specified, replace the thermostat.
(c) Check the valve lift.
Valve lift: 8.5 mm (0.335 in.) or more at 95°C (203°F)
If the valve lift is not as specified, replace the thermostat.
(d) Check that the valve is fully closed when the thermostat
is at low temperatures (below 40°C (104°F)).
If not closed, replace the thermostat.