2006 INFINITI QX56 cooling

REFRIGERANT LINESATC-189
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Revision: November 2009 2006 QX56
2. When checking for leaks, circle each fitting completely with the
probe as shown.
3. Move the probe along each component at a speed of approxi- mately 25 - 50 mm (1 - 2 in)/second as shown.
CHECKING PROCEDURE
NOTE:
To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette
smoke in the vicinity of the vehicle. Perform the leak test in a calm area (low air/wind movement) so that the
leaking refrigerant is not dispersed.
1. Turn the engine OFF.
2. Connect the manifold gauge set (J-39183-C) to the A/C service ports. Refer to ATC-171, "
SETTING OF
SERVICE TOOLS AND EQUIPMENT" .
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm
2 , 50 psi) above a temperature of
16 °C (61 °F). If less than specification, recover/evacuate and recharge the system with the specified
amount of refrigerant. Refer to ATC-171, "
HFC-134a (R-134a) Service Procedure" .
NOTE:
At temperatures below 16 °C (61 °F), leaks may not be detected since the system may not reach 345 kPa
(3.52 kg/cm
2 , 50 psi) pressure.
4. Perform the leak test from the high-pressure side (front A/C compressor discharge “a” to evaporator inlet
“f ” or rear piping connection “l”) to the low-pressure side (front A/C evaporator drain hose “g” to shaft seal
“k ” and rear A/C evaporator drain hose “o ” to piping connection “r”). Refer to ATC-173, "
Components" .
Clean the component to be checked and carefully move the electronic refrigerant leak detector probe
completely around the following connections and components.

Check the compressor shaft seal

Check the high and low-pressure pipe and hose fittings, relief valve, and compressor shaft seal

Check the liquid tank

Check the refrigerant pressure sensor

Check all around the service valves. Check that the service valve caps are screwed tightly on the ser-
vice valves (to prevent leaks).
NOTE:
After removing manifold gauge set (J-39183-C) from the service valves, wipe any residue from the ser-
vice valves to prevent any false readings by the electronic refrigerant leak detector (J-41995).

Evaporator
With engine OFF, turn blower fan on “High” for at least 15 seconds to dissipate any refrigerant trace in
the heater and cooling unit assembly. Wait a minimum of 10 minutes accumulation time (refer to the
manufacturer's recommended procedure for actual wait time) before inserting the electronic refrigerant
leak detector probe into the heater and cooling unit assembly drain hose.
SHA706E
SHA708EA

CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
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SECTION
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Revision: November 2009 2006 QX56
PRECAUTIONS .....................................................
..... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 2
Precautions for Liquid Gasket ............................. ..... 2
REMOVAL OF LIQUID GASKET SEALING ..... ..... 2
LIQUID GASKET APPLICATION PROCEDURE ..... 2
PREPARATION ...................................................... ..... 4
Special Service Tools .......................................... ..... 4
Commercial Service Tools ................................... ..... 4
OVERHEATING CAUSE ANALYSIS ..................... ..... 6
Troubleshooting Chart ......................................... ..... 6
COOLING SYSTEM ............................................... ..... 8
Cooling Circuit .......................................................... 8
System Drawing ....................................................... 9
ENGINE COOLANT ............................................... ... 10
Inspection ............................................................ ... 10
LEVEL CHECK ................................................ ... 10
CHECKING COOLING SYSTEM FOR LEAKS ... 10
CHECKING RESERVOIR CAP ........................ ... 10
CHECKING RADIATOR CAP ........................... ... 10
Changing Engine Coolant ................................... ... 10
DRAINING ENGINE COOLANT ...................... .... 11
REFILLING ENGINE COOLANT ..................... .... 11
FLUSHING COOLING SYSTEM ...................... ... 12
RADIATOR ............................................................. ... 14
Removal and Installation ..................................... ... 14
REMOVAL ........................................................ ... 14
INSTALLATION ................................................ ... 16INSPECTION AFTER INSTALLATION .............
... 16
Checking Radiator ............................................... ... 16
ENGINE COOLING FAN ........................................ ... 17
Removal and Installation (Crankshaft Driven Type) ... 17
REMOVAL ........................................................ ... 17
INSPECTION AFTER REMOVAL .................... ... 17
INSTALLATION ................................................ ... 17
INSPECTION AFTER INSTALLATION ............. ... 17
Removal and Installation (Motor Driven Type) .... ... 18
REMOVAL ........................................................ ... 18
INSTALLATION ................................................ ... 18
WATER PUMP ....................................................... ... 19
Removal and Installation ..................................... ... 19
REMOVAL ........................................................ ... 19
INSPECTION AFTER REMOVAL .................... ... 19
INSTALLATION ................................................ ... 19
INSPECTION AFTER INSTALLATION ............. ... 20
THERMOSTAT AND WATER PIPING ................... ... 21
Removal and Installation ..................................... ... 21
REMOVAL ........................................................ ... 21
INSPECTION AFTER REMOVAL .................... ... 22
INSTALLATION ................................................ ... 22
INSPECTION AFTER INSTALLATION ............. ... 22
SERVICE DATA AND SPECIFICATIONS (SDS) ... ... 23
Standard and Limit ............................................... ... 23
ENGINE COOLANT CAPACITY (APPROXI-
MATE) ............................................................... ... 23
THERMOSTAT ................................................. ... 23
RADIATOR ....................................................... ... 23

CO-4Revision: November 2009
PREPARATION
2006 QX56
PREPARATIONPFP:00002
Special Service ToolsEBS00RE4
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolsEBS00RE5
Tool number
(Kent-Moore No.)
Tool nameDescription
KV10111100
(J-37228)
Seal cutter Removing steel oil pan and rear timing chain
case
WS39930000
( — )
Tube pressure Pressing the tube of liquid gasket
EG17650301
(J-33984-A)
Radiator cap tester adapter Adapting radiator cap tester to radiator cap
and radiator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV991J0070
(J-45695)
Coolant refill tool For refilling engine cooling system
KV991J0010
(J-23688)
Engine coolant refractometer Checking concentration of ethylene glycol in
engine coolant
NT046
S-NT052
S-NT564
LMA053
WBIA0539E

CO-6Revision: November 2009
OVERHEATING CAUSE ANALYSIS
2006 QX56
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartEBS00RE6
SymptomCheck items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat stuck closed
—
Damaged fins Dust contamination or
paper clogging
Physical damage
Clogged radiator cooling
tube Excess foreign material
(rust, dirt, sand, etc.)
Water cut valve malfunction Excess foreign material
(rust, dirt, sand, etc.), phys-
ical damage
Reduced air flow Cooling fan does not oper-
ate
Fan assembly —
High resistance to fan rota-
tion
Damaged fan blades
Damaged radiator shroud —— —
Improper engine coolant
mixture ratio —— —
Poor engine coolant quality —Engine coolant density —
Insufficient engine coolant Engine coolant leaks Cooling hose
Loose clamp
Cracked hose
Water pump Poor sealing
Radiator cap Loose
Poor sealing
Radiator O-ring for damage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tank Exhaust gas leaks into
cooling systemCylinder head deterioration
Cylinder head gasket dete-
rioration

CO-8Revision: November 2009
COOLING SYSTEM
2006 QX56
COOLING SYSTEMPFP:21020
Cooling CircuitEBS00RE7
WBIA0404E

COOLING SYSTEMCO-9
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Revision: November 2009 2006 QX56
System DrawingEBS00RE8
WBIA0463E

CO-10Revision: November 2009
ENGINE COOLANT
2006 QX56
ENGINE COOLANTPFP:KQ100
InspectionEBS00RE9
LEVEL CHECK

Check if the engine coolant reservoir tank level is within MIN to
MAX level when engine is cool.

Adjust engine coolant level as necessary.
CHECKING COOLING SYSTEM FOR LEAKS
WARNING:
Never remove the radiator or reservoir cap when the engine is hot. Serious burns could occur from
high-pressure engine coolant escaping from the radiator or reservoir.

To check for leakage, apply pressure to the cooling system at
the reservoir filler neck using suitable tool and Tool.
CAUTION:
Higher pressure than specified may cause radiator damage.
NOTE:
In case that engine coolant decreases, replenish cooling system
with engine coolant.

If any concerns are found, repair or replace damaged parts.
CHECKING RESERVOIR CAP

Check reservoir cap relief pressure using suitable tool and Tool.
NOTE:
Apply engine coolant to the cap seal.

Replace the reservoir cap if there is any damage in the nega-
tive-pressure valve, or if the open-valve pressure is outside of
the limit.
CHECKING RADIATOR CAP
Inspect the radiator cap.
NOTE:
Thoroughly wipe out the radiator filler neck to remove any waxy residue or foreign material.

Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.

Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or the
metal retainer.
Changing Engine CoolantEBS00REA
WARNING:

To avoid being scalded, never change the coolant when the engine is hot.

Wrap a thick cloth around the cap to carefully remove the cap. First, turn the cap a quarter of a
turn to release any built-up pressure, then push down and turn the cap all the way to remove it.
SMA412B
Tool number : EG17650301 (J-33984-A)
Leakage test pressure : 137 kPa (1.4 kg/cm, 20 psi)
WBIA0612E
Tool number : EG17650301 (J-33984-A)
Standard: 95 - 125 kPa (0.97 - 1.28 kg/cm
2 , 14 - 18 psi)
WBIA0611E

ENGINE COOLANTCO-11
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DRAINING ENGINE COOLANT
1. Turn ignition switch ON and set temperature control lever all the way to HOT position or the highest tem-
perature position. Wait 10 seconds and turn ignition switch OFF.
2. Remove the engine front undercover using power tool.
3. Open the radiator drain plug at the bottom of the radiator, and remove the radiator filler cap. This is the only step required
when partially draining the cooling system (radiator only).
CAUTION:
Do not to allow the coolant to contact the drive belts.
4. When draining all of the coolant in the system for engine removal or repair, it is necessary to drain the cylinder block.
Remove the RH cylinder block drain plug to drain the right bank
and the oil cooler hose to drain the left bank as shown.
5. Remove the reservoir tank to drain the engine coolant, then clean the reservoir tank before installing it.
6. Check the drained coolant for contaminants such as rust, corrosion or discoloration. If the coolant is contaminated, flush the engine cooling system. Refer to CO-12, "
FLUSHING COOLING
SYSTEM" .
REFILLING ENGINE COOLANT
1. Close the radiator drain plug. Install the reservoir tank, cylinder block drain plug, and the oil cooler hose, if
removed for a total system drain or for engine removal or repair.

The radiator must be completely empty of coolant and water.

Apply sealant to the threads of the cylinder block drain plug. Use Genuine High Performance Thread
Sealant or equivalent. Refer to GI-46, "
Recommended Chemical Products and Sealants" .
2. Set the vehicle heater controls to the full HOT and heater ON position. Turn the vehicle ignition ON with the engine OFF as necessary to activate the heater mode.
3. Remove the vented reservoir cap and replace it with a non-vented reservoir cap before filling the cooling system.
WBIA0391E
PBIC0146E
WBIA0392E
Radiator drain plug : Refer to CO-14, "RADIATOR" .
RH cylinder block drain plug : Refer to EM-78, "
CYLINDER BLOCK" .