2000 LEXUS GS400 Service Repair Manual

CO0A9±03
B01881
CO±18
± COOLING (2JZ±GE)RADIATOR
1556 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. REMOVE ENGINE UNDER COVER
2. DRAIN ENGINE COOLANT
3. REMOVE AIR CLEANER INLET
4. REMOVE AIR CLEANER AND MAF METER AS-
SEMBLY
5. REMOVE RADIATOR AND ELECTRIC COOLING FAN
ASSEMBLY
(a) Disconnect the upper radiator hose from the radiator.
(b) Disconnect the lower radiator hose from the radiator.
(c) Disconnect the ECM outlet duct from the ECM box.
(d) Disconnect the wire for electric cooling fan from the clamp
on the electric cooling fan.
(e) Disconnect the 2 electric cooling fan connectors.
(f) Disconnect the ECT switch connector for electric cooling
fan.
(g) Disconnect the 2 oil cooler hoses for A/T from the radiator.
(h) Remove the 2 nuts and 2 upper radiator supports.
(i) Lift out the radiator and cooling fan assembly.
(j) Remove the 2 lower radiator supports.
6. REMOVE ELECTRIC COOLING FAN FROM RADIA-
TOR
(a) Disconnect the radiator reservoir hose from the radiator.
(b) Remove the 6 bolts and electric cooling fan.

CO0AA±01
CO1205
Dimension B
Stopper Bolt
Overhaul HandlePart A
ClawSST
B01865
Lock
PlateSST
Stopper BoltTank
B01867
Ta p
B02033
± COOLING (2JZ±GE)RADIATOR
CO±19
1557 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DISASSEMBLY
1. REMOVE PACKINGS
2. REMOVE RADIATOR CAP
3. REMOVE DRAIN PLUG
(a) Remove the drain plug.
(b) Remove the O±ring.
4. REMOVE ECT SWITCH
(a) Remove the ECT switch.
(b) Remove the O±ring.
5. ASSEMBLE SST
SST 09230±01010
(a) Install the claw to the overhaul handle, inserting it in the
hole in part A as shown in the diagram.
(b) While gripping the handle, adjust the stopper bolt so that
dimension B is as shown in the illustration.
Dimension B: 0.2 ± 0.3 mm (0.008 ± 0.012 in.)
NOTICE:
If this adjustment is not done the claw may be damaged.
6. UNCAULK LOCK PLATES
Using SST to release the caulking, squeeze the handle until
stopped by the stopper bolt.
SST 09230±01010
7. REMOVE TANKS AND O±RINGS
Lightly tap the bracket of the radiator (or radiator inlet or outlet)
with a soft±faced hammer, and remove the tank and the O±ring.
8. REMOVE OIL COOLER FROM LOWER TANK
(a) Loosen the nut, and remove the cooler pipe. Remove the
2 cooler pipes.
(b) Remove the 2 nuts and 2 plate washers.
(c) Remove the oil cooler and 2 O±rings.

CO09X±03
Z07402
Drain Plug
Drain Plug
B01611
Drain Plug
Rubber
HoseConnect
CO±2
± COOLING (2JZ±GE)COOLANT
1540 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REPLACEMENT
1. DRAIN ENGINE COOLANT
(a) Remove the radiator cap.
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.
(b) Loosen the 2 drain plugs (for the engine and radiator),
and drain the coolant.
HINT:
To prevent the coolant from spraying over the cylinder block,
connect the rubber hose (inside diameter 6 ± 8 mm) in the mar-
ket to the union pipe under the drain plug.
(c) Close the drain plugs.
Torque: 30 N´m (300 kgf´cm, 22 ft´lbf) for engine
2. FILL ENGINE COOLANT
(a) Slowly fill the system with coolant.

Use of improper coolants may damage engine cool-
ing system.

Use ºToyota Long Life Coolantº or equivalent and
mix it with plain water according to the manufac-
ture's directions.

Use of the coolant which includes more than 50%
[freezing protection down to ±35°C (±31°F)] or 60%
[freezing protection down to ±50°C (±58°F)] of eth-
ylene ±glycol is recommended, but not more than
70%.
NOTICE:

Do not use an alcohol type coolant or plain water
alone.

The coolant should be mixed with plain water (prefer-
able demineralized water or distilled water).
Capacity (w/ Heater):
7.7 liters (8.1 US qts, 6.8 lmp. qts)
(b) Install the radiator cap.
(c) Start the engine, and bleed the cooling system.
(d) Refill the reservoir with coolant until it reaches the ºFULLº
line.
3. CHECK ENGINE COOLANT FOR LEAKS
4. CHECK ENGINE COOLANT SPECIFIC GRAVITY COR-
RECTLY

CO0AB±03
B01862
75°
Pipe
CO0317O±Ring Normal X TwistedX Twisted
B01868
CORRECT
WRONG
Ta pTank
Plate
Lock
CO1206
Dimension B
Punch Assembly
Overhaul HandleStopper BoltPartSST
CO±20
± COOLING (2JZ±GE)RADIATOR
1558 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REASSEMBLY
1. INSTALL OIL COOLER TO LOWER TANK
(a) Install 2 new O±rings to the oil cooler.
(b) Install the oil cooler to the lower tank with the 2 plate
washers and 2 nuts.
Torque: 8.3 N´m (85 kgf´cm, 74 in.´lbf)
(c) Install the cooler pipes in the direction indicated in the il-
lustration.
Torque: 14.7 N´m (150 kgf´cm, 11 ft´lbf)
2. INSPECT LOCK PLATE FOR DAMAGE
HINT:

If the sides of the lock plate groove are deformed, reas-
sembly of the tank will be impossible.

Therefore, first correct any deformation with pliers or simi-
lar object. Water leakage will result if the bottom of the
lock plate groove is damaged or dented.
NOTICE:
The radiator can only be recaulked 2 times. After the 2nd
time, the radiator core must be replaced.
3. INSTALL NEW O±RINGS AND TANKS
(a) After checking that there are no foreign objects in the lock
plate groove, install a new O±ring without twisting it.
HINT:
When cleaning the lock plate groove, lightly rub it with sand pa-
per without scratching it.
(b) Install the tank without damaging the O±ring.
(c) Tap the lock plate with a soft±faced hammer so that there
is no gap between it and the tank.
4. ASSEMBLE SST
SST 09230±01010, 09231±14010
(a) Install the punch assembly to the overhaul handle, insert-
ing it in the hole in part A as shown in the illustration.
(b) While gripping the handle, adjust the stopper bolt so that
dimension B is as shown in the illustration.
Dimension B: 8.4 mm (0.331 in.)

B01863B01866B02081
8 7
6 5
43
2
1
Stopper
Bolt
SSTTank
Lock
Plate
B01861(1) (2)(3) (1)
(1)(1)(1) (3)
(3)
(3) (3)
B01864B01870B02082
B01869
H
± COOLING (2JZ±GE)RADIATOR
CO±21
1559 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. CAULK LOCK PLATE
(a) Lightly press SST against the lock plate in the order
shown in the illustration. After repeating this a few times,
fully caulk the lock plate by squeezing the handle until
stopped by the stopper plate.
SST 09230±01010
HINT:

Do not stake the areas protruding around the ports (1),
flange (2) and bracket (3).

The points shown in the illustration cannot be staked with
the SST. Use pliers or similar object and be careful not to
damage the core plates.
(b) Check the lock plate height (H) after completing the caulk-
ing.
Plate height (H): 7.40 ± 7.80 mm (0.2913 ± 0.3071 in.)
If not within the specified height, adjust the stopper bolt of the
handle again and caulk again.
6. INSTALL ECT SWITCH
(a) Install a new O±ring to the ECT switch.
(b) Install the ECT switch.
7. INSTALL DRAIN PLUG
(a) Install a new O±ring to the drain plug.

B01860
SST
B01871
Tank
Lock
Plate
O±Ring
CO±22
± COOLING (2JZ±GE)RADIATOR
1560 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Install the drain plug.
8. INSTALL RADIATOR CAP
9. INSPECT FOR WATER LEAKS
(a) Tighten the drain plug.
(b) Plug the inlet pipes of the radiator with SST.
SST 09230±01010
(c) Using a radiator cap tester, apply pressure to the radiator.
Test pressure: 177 kPa (1.8 kgf/cm
2, 26 psi)
(d) Submerge the radiator in water.
(e) Inspect for leaks.
HINT:
On radiators with resin tanks, there is a clearance between the
tank and lock plate where a minute amount of air will remain,
giving the appearance of an air leak when the radiator is sub-
merged in water. Therefore, before doing the water leak test,
first swish the radiator around in the water until all air bubbles
disappear.
10. INSTALL NEW PACKINGS

CO0AC±01
B01881
± COOLING (2JZ±GE)RADIATOR
CO±23
1561 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
1. INSTALL ELECTRIC COOLING FAN TO RADIATOR
(a) Install the electric cooling fan with the 6 bolts.
Torque: 5.0 N´m (50 kgf´cm, 44 in.´lbf)
(b) Connect the radiator reservoir hose to the radiator.
2. INSTALL RADIATOR AND ELECTRIC COOLING FAN
ASSEMBLY
(a) Install the 2 lower radiator supports to the radiator.
(b) Attach the 2 lower radiator supports on the radiator to the
body bracket.
(c) Install the radiator and electric cooling fan assembly with
the 2 upper radiator supports and 2 nuts.
Torque: 13.5 N´m (135 kgf´cm, 10 ft´lbf)
(d) Connect these parts:

Upper radiator hose to radiator

Lower radiator hose to radiator

ECM outlet duct to ECM box

Wire for electric cooling fan to clamp on electric
cooling fan

2 electric cooling fan connectors

ECT switch connector for electric cooling fan

2 oil cooler hoses for A/T to radiator
3. INSTALL AIR CLEANER AND MAF METER AS-
SEMBLY
4. INSTALL AIR CLEANER INLET
5. FILL WITH ENGINE COOLANT
6. START ENGINE AND CHECK FOR ENGINE COOLANT
AND A/T FLUID LEAKS
7. INSTALL ENGINE UNDER COVER

B01900
CO0AD±03
B00922
ECT
Switch
Connector
B02072
B02073
Ammeter
Battery(+)
(±)
CO±24
± COOLING (2JZ±GE)ELECTRIC COOLING FAN
1562 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC COOLING FAN
ON±VEHICLE INSPECTION
1. CHECK COOLING FAN OPERATION WITH LOW
TEMPERATURE (Below 83°C (181°F))
(a) Turn the ignition switch ON.
(b) Check that the cooling fan stops.
If not, check the cooling fan relay and ECT switch, and check
for a separated connector or severed wire between the cooling
fan relay and ECT switch.
(c) Disconnect the ECT switch connector.
(d) Check that the cooling fan rotates.
If not, check the fuses, radiator fan main relay, cooling fan relay,
cooling fan, and check for a short circuit between the cooling
fan relay and ECT switch.
(e) Reconnect the ECT switch connector.
2. CHECK COOLING FAN OPERATION WITH HIGH
TEMPERATURE (Above 93°C (199°F))
(a) Start the engine, and raise coolant temperature to above
93°C (199°F).
HINT:
Coolant temperature is the detected value by the ECT switch
on the radiator lower tank.
(b) Check that the cooling fan rotates.
If not, replace the ECT switch.
3. INSPECT COOLING FANS
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 8.5 ± 11.5 A at 20°C (68°F)
(d) Reconnect the cooling fan connector.