2000 LEXUS GS400 Service Repair Manual

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.

CO0A5±01
P 1111 7
ProtrusionJiggle Valve
± COOLING (2JZ±GE)THERMOSTAT
CO±13
1551 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
1. PLACE THERMOSTAT IN WATER INLET
(a) Install a new gasket to the thermostat.
(b) Align the jiggle valve of the thermostat with the protrusion
of the water inlet.
2. INSTALL WATER INLET
Install the water inlet with the 2 nuts.
Torque: 9.0 N´m (90 kgf´cm, 80 in.´lbf)
3. FILL WITH ENGINE COOLANT
4. START ENGINE AND CHECK FOR COOLANT LEAKS

CO0A6±01
CO±14
± COOLING (2JZ±GE)RADIATOR
1552 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
RADIATOR
ON±VEHICLE CLEANING
CLEAN RADIATOR
Using water or a steam cleaner, remove any mud or dirt from the radiator core.
NOTICE:
If using a high pressure type cleaner, be careful not to deform the fins of the radiator core. (i.e. Main-
tain a distance between the cleaner nozzle and radiator core.)

CO0A7±01
CO1242
Radiator Cap Tester
Radiator Cap
30° or More
B01882
Radiator Cap Tester
± COOLING (2JZ±GE)RADIATOR
CO±15
1553 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ON±VEHICLE INSPECTION
1. REMOVE RADIATOR CAP
Remove the radiator cap from the radiator.
CAUTION:
To avoid the danger of being burned, do not remove the ra-
diator cap while the engine and radiator are still hot, as fluid
and steam can be blown out under pressure.
2. INSPECT RADIATOR CAP
NOTICE:

If the radiator cap has contaminations, always rinse
it with water.

Before using a radiator cap tester, wet the relief valve
and pressure valve with engine coolant or water.

When performing steps (a) and (b) below, keep the
tester at an angle of over 30° above the horizontal.
(a) Using a radiator cap tester, slowly pump the tester and
check that air is coming from the vacuum valve.
Pump speed: 1 push/(3 seconds or more)
NOTICE:
Push the pump at a constant speed.
If air is not coming from the vacuum valve, replace the radiator
cap.
(b) Pump the radiator cap tester, and measure the relief valve
opening pressure.
Pump speed: 1 push within 1 second
NOTICE:
This pump speed is for the first pump only (in order to close
the vacuum valve). After this, the pump speed can be re-
duced.
Standard opening pressure:
93 ± 123 kPa (0.95 ± 1.25 kgf/cm
2, 13.5 ± 17.8 psi)
Minimum opening pressure:
78 kPa (0.8 kgf/cm
2, 11.4 psi)
HINT:
Use the tester's maximum reading as the opening pressure.
If the opening pressure is less than minimum, replace the radia-
tor cap.
3. INSPECT COOLING SYSTEM FOR LEAKS
(a) Fill the radiator with coolant and attach a radiator cap tes-
ter.
(b) Warm up the engine.
(c) Pump it to 118 kPa (1.2 kgf/cm
2, 17.1 psi), and check that
the pressure does not drop.
If the pressure drops, check the hoses, radiator or water pump
for leaks. If no external leaks are found, check the heater core,
cylinder block and head.
4. REINSTALL RADIATOR CAP

CO0A8±01
B02029
Air Cleaner Inlet
Upper Radiator Support
Air Cleaner and MAF
Meter Assembly
Lower Radiator Support
Intake Air Resonator
Engine Under Cover
x 18
ECT Switch
Connector for
Electric Cooling
Fan Lower Radiator Hose
Upper Radiator Support
Upper Radiator Hose
ECM Outlet Duct
Wire Clamp
Electric Cooling
Fan Connector
Oil Cooler Hose
for A/T Engine Wire
Clamp MAF Meter Connector
Radiator and Electric
Cooling Fan Assembly
EVAP Hose
CO±16
± COOLING (2JZ±GE)RADIATOR
1554 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPONENTS

B00917
Radiator Reservoir Hose
Electric Cooling Fan
Assembly
Radiatorx 6
B01859

Packing Upper Tank

O±Ring
Core
Drain Plug

Non±reusable part

Packing

Packing

Packing

Packing

Packing

O±Ring

O±RingPipe
Pipe
Plate Washer Nut
Nut

O±Ring
ECT Switch for Electric
Cooling Fan

O±Ring

O±Ring
Lower Tank
Radiator Cap
Oil Cooler
± COOLING (2JZ±GE)RADIATOR
CO±17
1555 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)