Engine cooling system INFINITI QX56 2008 Factory Owner's Guide
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EM-52
< ON-VEHICLE REPAIR >
TIMING CHAIN
a. Apply engine oil onto the threaded parts of the bolt and seating area.
b. Select the one most visible notch of the four on the bolt flange.Corresponding to the selected notch, put a alignment mark
(such as paint) on the crankshaft pulley.
14. Rotate the crankshaft pulley in normal direction (clockwise when viewed from engine front) to check for parts interference.
15. Installation of the remaining components is in the reverse of order of removal.
INSPECTION AFTER INSTALLATION
• Before starting engine, check oil/fluid levels incl uding engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-12, "
Fluids and Lubricants".
• Use procedure below to check for fuel leakage.
• Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel leak- age at connection points.
• Start engine. With engine speed increased, che ck again for fuel leakage at connection points.
• Run engine to check for unusual noise and vibration.
• Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including
engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to spec-
ified level, if necessary.
• Summary of the inspection items:
*Power steering fluid, brake fluid, etc.
Crankshaft pulley bolt torque
Step 1 : 93.1 N·m (9.5 kg-m, 69 ft-lb)
Step 2 : additional 90 ° (angle tightening)
KBIA2519E
Item Before starting engine Engine runningAfter engine stopped
Engine coolant LevelLeakage Level
Engine oil LevelLeakage Level
Transmission/
transaxle fluid A/T and CVT Models
LeakageLevel/Leakage Leakage
M/T Models Level/Leakage LeakageLevel/Leakage
Other oils and fluids* LevelLeakage Level
Fuel LeakageLeakage Leakage
Exhaust gas —Leakage —
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CYLINDER HEADEM-69
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• Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between d1 and d2 exceeds
the limit, replace the bolt with a new one.
• If reduction of diameter appears in a position other than d2, use it as d2 point.
INSTALLATION
1. Install a new cylinder head gasket.
2. Install the cylinder head. Follow the steps below to tighten the bolts in the numerical order shown.
CAUTION:
• If cylinder head bolts are re-used, check their diameters
before installation. Refer to "Cylinder Head Bolts Diame-
ter".
a. Apply engine oil to threads and seating surface of the bolts.
b. Measure the tightening angle using Tool. CAUTION:
Measure the tightening angl e using Tool. Do not measure
visually.
3. Installation of the remaining components is in the reverse order of removal.
INSPECTION AFTER INSTALLATION
• Before starting engine, check oil/fluid levels incl uding engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-12, "
Fluids and Lubricants".
• Use procedure below to check for fuel leakage.
• Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel leak-
age at connection points.
• Start engine. With engine speed increased, check again for fuel leakage at connection points.
• Run engine to check for unusual noise and vibration.
• Warm up engine thoroughly to make sure there is no leak age of fuel, exhaust gas, or any oils/fluids including
engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to spec- ified level, if necessary.
• Summary of the inspection items: Limit (d1 - d2) : 0.23 mm (0.0091 in)
KBIA0189E
PBIC0068E
Step a : 44.1 N·m (4.5 kg-m, 33 ft-lb)
Step b : 70°
clockwise
Step c : Loosen in the reverse order of tightening.
Step d : 44.1 N·m (4.5 kg-m, 33 ft-lb)
Step e : 60 ° clockwise
Step f : 60° clockwise
WBIA0603E
Tool number : KV10112100 (BT-8653-A)
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ENGINE ASSEMBLYEM-81
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• Start engine. With engine speed increased, check again for fuel leakage at connection points.
• Run engine to check for unusual noise and vibration.
• Warm up engine thoroughly to make sure there is no leak
age of fuel, exhaust gas, or any oils/fluids including
engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to spec- ified level, if necessary.
• Summary of the inspection items:
*Power steering fluid, brake fluid, etc. Item
Before starting engine Engine runningAfter engine stopped
Engine coolant LevelLeakage Level
Engine oil LevelLeakage Level
Transmission/
transaxle fluid A/T and CVT Models
LeakageLevel/Leakage Leakage
M/T Models Level/Leakage LeakageLevel/Leakage
Other oils and fluids* LevelLeakage Level
Fuel LeakageLeakageLeakage
Exhaust gas —Leakage —
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PRECAUTIONSHA-5
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General Refrigerant PrecautionINFOID:0000000001516632
WARNING:
• Do not release refrigerant into the air. Use appr oved recovery/recycling equipment to capture the
refrigerant every time an air co nditioning system is discharged.
• Always wear eye and hand protection (goggles and gloves) when working with any refrigerant or air
conditioning system.
• Do not store or heat refrigerant containers above 52 °C (125° F).
• Do not heat a refrigerant containe r with an open flame; if container warming is required, place the
bottom of the container in a warm pail of water.
• Do not intentionally drop, puncture, or incinerate refrigerant containers.
• Keep refrigerant away from open flames: poison ous gas will be produced if refrigerant burns.
• Refrigerant will displace oxygen, therefore be certain to work in well ventilated areas to prevent suf- focation.
• Do not pressure test or leak test HFC-134a (R-134a) service equipment and/or vehicle air condition-
ing systems with compressed air during repair. Some mixtures of air and HFC-134a (R-134a) have
been shown to be combustible at elevated pressures. These mixtures, if ignited, may cause injury or
property damage. Additional health and safety information may be obtained from refrigerant manu-
facturers.
Precaution for Leak Detection DyeINFOID:0000000001516633
• The A/C system contains a fluorescent leak detection dy e used for locating refrigerant leaks. An ultraviolet
(UV) lamp is required to illuminate the dye when inspecting for leaks.
• Always wear fluorescence enhancing UV safety goggles to protect your eyes and enhance the visibility of
the fluorescent dye.
• The fluorescent dye leak detector is not a replacement for an electronic refrigerant leak detector. The fluo-
rescent dye leak detector should be used in conjuncti on with an electronic refrigerant leak detector (J-
41995).
• For your safety and the customer's satisfaction, read and follow all manufacturer's operating instructions and precautions prior to performing work.
• A compressor shaft seal should not be repaired because of dye seepage. The compressor shaft seal should
only be repaired after confirming the leak with an electronic refrigerant leak detector (J-41995).
• Always remove any dye from the leak area after repairs are complete to avoid a misdiagnosis during a future service.
• Do not allow dye to come into contact with paint ed body panels or interior components. If dye is spilled,
clean immediately with the approved dye cleaner. Fluorescent dye left on a surface for an extended period of
time cannot be removed.
• Do not spray the fluorescent dye cleaning agent on hot surfaces (engine exhaust manifold, etc.).
• Do not use more than one refrigerant dye bot tle (1/4 ounce / 7.4 cc) per A/C system.
• Leak detection dyes for HFC-134a (R-134a) and CFC-12 (R -12) A/C systems are different. Do not use HFC-
134a (R-134a) leak detection dye in CFC-12 (R-12) A/ C systems or CFC-12 (R-12) leak detection dye in
HFC-134a (R-134a) A/C systems or A/C system damage may result.
• The fluorescent properties of the dye will remain for over three (3) years unless a compressor failure occurs.
A/C Identification LabelINFOID:0000000001516634
Vehicles with factory installed fluorescent dye have this identification label on the underside of hood.
Precaution for Refrigerant ConnectionINFOID:0000000001516635
A new type refrigerant connection has been introduced to all refrigerant lines except the following locations.
• Expansion valve to cooling unit
• Evaporator pipes to evaporator (inside cooling unit)
• Refrigerant pressure sensor
FEATURES OF NEW TYPE REFRIGERANT CONNECTION
• The O-ring has been relocated. It has also been provided with a groove for proper installation. This reduces the possibility of the O-ring being caught in, or damaged by , the mating part. The sealing direction of the O-
ring is now set vertically in relation to the contacting surface of the mating part to improve sealing character-
istics.
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HA-22
< ON-VEHICLE MAINTENANCE >
OIL
OIL
Maintenance of Oil Quantity in CompressorINFOID:0000000001516645
The oil in the compressor circulates through the system with the refrigerant. Add oil to compressor when
replacing any component or after a large refrigerant leakage has occurred. It is important to maintain the spec-
ified amount.
If oil quantity is not maintained properly, the following malfunctions may result:
• Lack of oil: May lead to a seized compressor
• Excessive oil: Inadequate cooling (thermal exchange interference)
OIL
Name: NISSAN A/C System Oil Type S or equivalent
CHECKING AND ADJUSTING
CAUTION:
If excessive oil leakage is noted, do not perform the oil return operation.
Start the engine and set the following conditions:
Test Condition
• Engine speed: Idling to 1,200 rpm
• A/C switch: On
• Blower fan speed: MAX position
• Temp. control: Optional [Set so that intake air temperature is 25 ° to 30 ° C (77 ° to 86 °F)]
• Intake position: Recirculation ( )
• Perform oil return operation for about ten minutes
Adjust the oil quantity according to the following table.
Oil Adjusting Procedure for Components Replacement Except Compressor
After replacing any of the following major components, add the correct amount of oil to the system.
Amount of Oil to be Added
• *1: If refrigerant leak is small, no addition of oil is needed.
Oil Adjustment Procedure for Compressor Replacement
Part replaced Oil to be added to system
Remarks
Amount of oil
m (US fl oz, Imp fl oz)
Front evaporator 75 (2.5, 2.6)—
Rear evaporator 75 (2.5, 2.6)—
Condenser 75 (2.5, 2.6)—
Liquid tank 5 (0.2, 0.2)Add if compressor is not replaced.
In case of refrigerant leak 30 (1.0, 1.1)
Large leak
— Small leak *1
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ELECTRICAL LEAK DETECTORHA-27
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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 t here 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 HA-20, "
HFC-134a (R-
134a) Service Procedure".
3. Check if the A/C refrigerant pressu re 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/ev acuate and recharge the system with the specified
amount of refrigerant. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
NOTE:
At temperatures below 16 °C (61° F), leaks may not be detected sinc e 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 HA-29, "
Component". 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 fitt ings, 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.
NOTE:
SHA706E
SHA708EA
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LOW-PRESSURE PIPEHA-37
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LOW-PRESSURE PIPE
Removal and Installation for Low-Pressure PipeINFOID:0000000001516655
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Remove the cowl top and the cowl top extension. Refer to EXT-18, "
Removal and Installation".
3. Remove the low-pressure pipe. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
Refer to HA-29, "
Component".
CAUTION:
• Replace the O-ring of the high/low-pressure pipe with a new one, then apply compressor oil to it
when installing it.
• After charging refrigerant, check for leaks.
Removal and Installation for Rear High- and Low-Pressure A/C and Heater Core Pipes
INFOID:0000000002975446
REMOVAL
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
3. Disconnect the underfloor rear heater hoses (1 and 2) from the rear heater pipes underneath the vehicle.
• : Front
4. Remove the rear high- and low-pressure pipes bolt (A) to dis- connect the rear high- and low-pressure pipes from the under-
floor rear high- and low-pressure pipes underneath the vehicle.
CAUTION:
Cap or wrap the joint of the pipes with suitable material
such as vinyl tape to avo id the entry of air.
5. Remove the rear high- and low-pressure pipes nuts (B).
NOTE:
The remaining steps are performed inside the rear luggage area of the vehicle.
6. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
7. Disconnect the rear heater core hoses (1 and 2) from the rear heater core (3).
• : Front
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HIGH-PRESSURE PIPEHA-41
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HIGH-PRESSURE PIPE
Removal and Installation for High-Pressure PipeINFOID:0000000001516657
REMOVAL
1. Remove the cowl top extension. Refer to EXT-18, "Removal and Installation".
2. Disconnect the battery negative terminal and positive battery terminal.
3. Reposition the IPDM E/R aside.
4. Remove the front right wheel and tire assembly. Refer to WT-48, "
Rotation".
5. Remove front right fender protector. Refer to EXT-23, "
Removal and Installation"
6. Position aside the front floor insulator.
7. Discharge the refrigerant. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
8. Remove the low pressure pipe. Refer to HA-37, "
Removal and Installation for Low-Pressure Pipe".
9. Remove the high-pressure pipe. CAUTION:
Cap or wrap the joint of the pipe with suitable mate rial such as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
Refer to HA-29, "
Component".
CAUTION:
• Replace the O-ring of the high-pressure pipe with a new one, then apply compressor oil to it when
installing it.
• After charging refrigerant, check for leaks.
Removal and Installation for Rear High- and Low-Pressure A/C and Heater Core Pipes
INFOID:0000000002975448
REMOVAL
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
3. Disconnect the underfloor rear heater hoses (1 and 2) from the rear heater pipes underneath the vehicle.
• : Front
4. Remove the rear high- and low-pressure pipes bolt (A) to dis- connect the rear high- and low-pressure pipes from the under-
floor rear high- and low-pressure pipes underneath the vehicle.
CAUTION:
Cap or wrap the joint of the pipes with suitable material
such as vinyl tape to avo id the entry of air.
5. Remove the rear high- and low-pressure pipes nuts (B).
NOTE:
The remaining steps are performed inside the rear luggage area of the vehicle.
6. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
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HAC-110
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
INSUFFICIENT COOLING
NO >> Check water valve circuit. Refer to
HAC-76, "Water Valve Diagnosis Procedure".
9.CHECK RECOVERY/RECYCLING EQUIPMENT BEFORE USAGE
Check recovery/recycling equipment before connecting to vehicle. Verify there is no pressure in the recovery/
recycling equipment by checking the gauges. If pressure exists, recover refrigerant from equipment lines.
>> GO TO 10.
10.CHECK REFRIGERANT PURITY
1. Connect recovery/recycling equipment to vehicle.
2. Confirm refrigerant purity in supply tank us ing recovery/recycling and refrigerant identifier.
Is the inspection result normal?
YES >> GO TO 11.
NO >> Check contaminated refrigerant. Refer to HAC-122, "
Working with HFC-134a (R-134a)".
11 .CHECK FOR EVAPORATOR FREEZE UP
Start engine and run A/C. Check for evaporator freeze up.
Does evaporator freeze up?
YES >> Perform diagnostic work flow. Refer to HAC-110, "Diagnostic Work Flow".
NO >> GO TO 12.
12.CHECK REFRIGERANT PRESSURE
Check refrigerant pressure with manifold gauge connected. Refer to HAC-113, "
Performance Chart".
Is the inspection result normal?
YES >> Perform diagnostic work flow. Refer to HAC-110, "Diagnostic Work Flow".
NO >> GO TO 13.
13.CHECK AIR DUCTS
Check ducts for air leaks.
Is the inspection result normal?
YES >> System OK.
NO >> Repair air leaks.
Diagnostic Work FlowINFOID:0000000001679831
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INSUFFICIENT COOLINGHAC-113
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Performance ChartINFOID:0000000001679832
TEST CONDITION
Testing must be performed as follows:
TEST READING
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
Vehicle location Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door window Open
Hood Open
TEMP. Max. COLD
Mode switch (Ventilation) set
Recirculation (REC) switch (Recirculation) set
Blower speed Max. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet Discharge air temperature at center ventilator
°C ( °F)
Relative humidity
% Air temperature
°C ( °F)
50 - 60 20 (68)
9.9 - 13.9 (50 - 57)
25 (77) 14.6 - 18.6 (58 - 65)
30 (86) 16.8 - 21.8 (62 - 71)
35 (95) 21.1 - 27.1 (70 - 81)
40 (104) 25.3 - 31.5 (78 - 89)
60 - 70 20 (68)
11.4 - 15.2 (53 - 59)
25 (77) 15.5 - 20.0 (60 - 68)
30 (86) 19.9 - 25.0 (68 - 77)
35 (95) 24.5 - 29.6 (76 - 85)
40 (104) 28.7 - 34.9 (84 - 95)
Ambient air High-pressure (Discharge side)
kPa (kg/cm
2 , psi) Low-pressure (Suction side)
kPa (kg/cm2 , psi)
Relative humidity
% Air temperature
°C ( °F)
50 - 70 20 (68)
1020 - 1250
(10.4 - 12.7, 147.9 - 181.3) 160 - 190
(1.63 - 1.94, 23.2 - 27.6)
25 (77) 1236 - 1510
(12.6 - 15.4, 179.2 - 219) 206 - 245
(2.1 - 2.5, 29.9 - 35.6)
30 (86) 1569 - 1,922
(16.0 - 19.6, 227.6 - 278.8) 265 - 324
(2.7 - 3.3, 38.4 - 46.9)
35 (95) 1,697 - 2079
(17.3 - 21.2, 246.1 - 301.5) 304 - 363
(3.1 - 3.7, 44.1 - 52.6)
40 (104) 1971 - 2403
(20.1 - 24.5, 285.9 - 348.5) 373 - 451
(3.8 - 4.6, 54.0 - 65.4)
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