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ENGINE COOLANT
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Revision: August 20072004 QX56
REFILLING ENGINE COOLANT
Refer to MA-13, "REFILLING ENGINE COOLANT" .
FLUSHING COOLING SYSTEM
Refer to MA-14, "FLUSHING COOLING SYSTEM" .
Page 1093 of 3371
CO-10Revision: August 2007
RADIATOR
2004 QX56
RADIATORPFP:21400
Removal and InstallationEBS00I4Y
WAR NIN G:
Never remove the radiator cap when the engine is hot. Serious burns could occur from high-pressure
engine coolant escaping from the radiator.
REMOVAL
CAUTION:
Perform when the engine is cold.
1. Remove engine room cover. Refer to EM-11, "
ENGINE ROOM COVER" .
2. Drain engine coolant from the radiator. Refer to MA-12, "
DRAINING ENGINE COOLANT" .
3. Remove air cleaner and air duct assembly. Refer to EM-14, "
REMOVAL" .
4. Disconnect A/T fluid cooler hoses.
Install blind plug to avoid leakage of A/T fluid.
5. Disconnect radiator upper and lower hoses from radiator.
WBIA0519E
1. Radiator 2. Bolt 3. Mounting rubber
4. A/T fluid cooler hose 5. Radiator hose (lower) 6. Flaps
7. Radiator shroud (upper) 8. Radiator shroud (lower) 9. Drain plug
10. Radiator hose (upper) 11. Reservoir tank hose 12. By-pass hose
13. Reservoir tank 14. Reservoir tank cap
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CO-12Revision: August 2007
RADIATOR
2004 QX56
10. Lift up and remove the radiator.
CAUTION:
Do not damage or scratch air conditioner condenser and
radiator core when removing.
INSTALLATION
Installation is in the reverse order of removal.
INSPECTION AFTER INSTALLATION
Check for leaks of engine coolant. Refer to CO-8, "CHECKING COOLING SYSTEM FOR LEAKS" .
Start and warm up the engine. Visually make sure that there are no leaks of the engine coolant.
Checking RadiatorEBS00NKC
Check radiator for mud or clogging. If necessary, clean radiator as follows.
CAUTION:
Be careful not to bend or damage the radiator fins.
When radiator is cleaned without removal, remove all surrounding parts such as cooling fan, radi-
ator shroud and horns. Then tape the harness and electrical connectors to prevent water from
entering.
1. Apply water by hose to the back side of the radiator core vertically downward.
2. Apply water again to all radiator core surfaces.
3. Stop washing when dirt and debris no longer flow out from the radiator.
4. Blow air into the back side of radiator core vertically downward.
Use compressed air lower than 490 kPa (5 kg/cm2 , 71 psi) and keep distance more than 30 cm (11.8
in).
5. Blow air again into all the radiator core surfaces until no water sprays out.
PBIC1536E
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ENGINE COOLING FAN
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ENGINE COOLING FANPFP:21140
Removal and Installation (Crankshaft Driven Type)EBS00I51
REMOVAL
1. Remove air duct. Refer to EM-14, "REMOVAL" .
2. Remove the engine front undercover using power tool.
3. Remove the lower radiator shroud. Refer to CO-10, "
RADIATOR" .
4. Remove cooling fan.
INSPECTION AFTER REMOVAL
Fan Coupling
Inspect fan coupling for oil leakage and bimetal conditions.
Fan Bracket
Visually check that there is no significant looseness in the fan
bracket shaft, and that it turns smoothly by hand.
If there are any unusual concerns, replace the cooling fan pulley.
INSTALLATION
Installation is in the reverse order of removal.
Install cooling fan with its front mark “F” facing front of engine. Refer to CO-13, "Removal and Installation
(Crankshaft Driven Type)" .
INSPECTION AFTER INSTALLATION
Check for leaks of the engine coolant. Refer to CO-8, "CHECKING COOLING SYSTEM FOR LEAKS" .
Start and warm up the engine. Visually make sure that there are no leaks of the engine coolant.
1. Cooling fan 2. Fan coupling 3. Fan bracket
4. Cooling fan pulley
WBIA0632E
SL C0 72
WBIA0418E
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WATER PUMP
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WATER P UM PPFP:21020
Removal and InstallationEBS00I53
CAUTION:
When removing water pump, be careful not to get engine coolant on drive belt.
Water pump cannot be disassembled and should be replaced as a unit.
REMOVAL
1. Drain engine coolant so that no engine coolant comes out from water pump fitting hole. Refer to MA-12,
"DRAINING ENGINE COOLANT" .
CAUTION:
Perform when the engine is cold.
2. Remove the engine front undercover using power tool.
3. Remove the air duct and resonator assembly. Refer to EM-14, "
Removal and Installation" .
4. Remove the drive belt. Refer to EM-12, "
Removal and Installation" .
5. Remove the water pump pulley.
6. Remove the water pump.
Engine coolant will leak from the cylinder block, so have a receptacle ready below.
CAUTION:
Handle water pump vane so that it does not contact any other parts.
INSPECTION AFTER REMOVAL
Visually check that there is no significant dirt or rusting on the
water pump body and vane.
Make sure there is no looseness in the vane shaft, and that it
turns smoothly when rotated by hand.
If there are any unusual concerns, replace the water pump
assembly.
INSTALLATION
Installation is in the reverse order of removal.
KBIA2543E
1. Gasket 2. Water pump 3. Water pump pulley
KBIA2552E
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CO-16Revision: August 2007
WATER PUMP
2004 QX56
For bleeding the air from the cooling system, refer to MA-13, "REFILLING ENGINE COOLANT" .
INSPECTION AFTER INSTALLATION
Check for leaks of engine coolant. Refer to CO-8, "CHECKING COOLING SYSTEM FOR LEAKS" .
Start and warm up engine. Visually make sure that there are no leaks of engine coolant.
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THERMOSTAT AND WATER PIPING
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THERMOSTAT AND WATER PIPINGPFP:21200
Removal and InstallationEBS00I54
REMOVAL
Removal of Thermostat
1. Drain engine coolant from the radiator. Refer to MA-12, "DRAINING ENGINE COOLANT" .
CAUTION:
Perform when engine is cold.
2. Remove air duct and resonator assembly. Refer to EM-14, "
REMOVAL" .
3. Remove engine room cover using power tools.
4. Disconnect water suction hose from water inlet.
5. Remove water inlet and thermostat.
Removal of Thermostat Housing, Water Outlet and Heater Pipe
1. Remove intake manifold. Refer to EM-15, "REMOVAL" .
2. Remove thermostat housing, water outlet and heater pipe.
Removal of Water Cut Valve
1. Drain engine coolant from the radiator. Refer to MA-12, "DRAINING ENGINE COOLANT" .
KBIA2501E
1. Heater pipe 2. Gasket 3. Water outlet
4. Gasket 5. O-ring 6. O-ring
7. Thermostat housing 8. Rubber ring 9. Thermostat
10. Water inlet 11. Water suction hose 12. Water suction pipe
13. Gasket 14. Heater pipe
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CO-18Revision: August 2007
THERMOSTAT AND WATER PIPING
2004 QX56
CAUTION:
Perform when the engine is cold.
2. Remove air duct and resonator assembly. Refer to EM-14, "
REMOVAL" .
3. Remove engine room cover using power tools.
4. Disconnect heater hose (heater core side).
5. Remove heater hose bracket.
6. Disconnect the water cut valve connector.
7. Remove the water cut valve
INSPECTION AFTER REMOVAL
Place a thread so that it is caught in the valve of the thermostat.
Immerse fully in a container filled with water. Heat while stirring.
The valve opening temperature is the temperature at which the
valve opens and falls from the thread.
Continue heating. Check the full-open lift amount.
After checking the full-open lift amount, lower the water temper-
ature and check the valve closing temperature.
Standard values:
INSTALLATION
Installation is in the reverse order of removal.
Installation of Thermostat
Install the thermostat with the whole circumference of each
flange part fit securely inside the rubber ring as shown.
Install the thermostat with the jiggle valve facing upwards.
Installation of Water Outlet Pipe and Heater Pipe
First apply a neutral detergent to the O-rings, then quickly insert the insertion parts of the water outlet pipe and
heater pipe into the installation holes.
INSPECTION AFTER INSTALLATION
Check for leaks of the engine coolant. Refer to CO-8, "CHECKING COOLING SYSTEM FOR LEAKS" .
Start and warm up the engine. Visually make sure that there is no leaks of the engine coolant.
SL C2 52 B
Thermostat
Valve opening temperature 80 - 84°C (176 - 183° F)
Full-open lift amount More than 10 mm/ 95°C (0.39 in/ 203°F)
Valve closing temperature 77°C (171°F) or higher
KBIA2502E