CO-36
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OVERHEATING CAUSE ANALYSIS
Revision: 2007 April2007 M35/M45
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartNBS004RB
Symptom Check items
Cooling sys-
tem parts
malfunctionPoor heat transferWater pump malfunction Worn or loose drive belt
— Thermostat and water con-
trol valve stuck closed—
Damaged finsDust contamination or
paper clogging
Physical damage
Clogged radiator cooling
tubeExcess foreign material
(rust, dirt, sand, etc.)
Reduced air flowCooling 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 coolantEngine coolant leaksCooling hoseLoose clamp
Cracked hose
Water pump Poor sealing
Radiator capLoose
Poor sealing
RadiatorO-ring for damage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tankExhaust gas leaks into
cooling systemCylinder head deterioration
Cylinder head gasket dete-
rioration
CO-40
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ENGINE COOLANT
Revision: 2007 April2007 M35/M45
ENGINE COOLANTPFP:KQ100
InspectionNBS004RE
LEVEL CHECK
Check if the reservoir tank engine coolant level is within the
“MIN” to “MAX” when engine is cool.
Adjust the engine coolant level as necessary.
LEAK CHECK
To check for leaks, apply pressure to the cooling system with
radiator cap tester (commercial service tool) (A) and radiator
cap tester adapter (commercial service tool) (B).
WARNING:
Do not remove radiator cap when engine is hot. Serious
burns could occur from high-pressure engine coolant
escaping from thermostat housing.
CAUTION:
Higher testing pressure than specified may cause radiator
damage.
NOTE:
In a case engine coolant decreases, replenish radiator with engine coolant.
If anything is found, repair or replace damaged parts.
Changing Engine CoolantNBS004RF
WARNING:
To avoid being scalded, do not change engine coolant when engine is hot.
Wrap a thick cloth around radiator cap and carefully remove radiator cap. First, turn radiator cap a
quarter of a turn to release built-up pressure. Then turn radiator cap all the way.
DRAINING ENGINE COOLANT
1. Remove engine room cover (RH and LH). Refer to EM-173, "ENGINE ROOM COVER" .
2. Remove engine cover with power tool. Refer to EM-179, "
INTAKE MANIFOLD" .
3. Open radiator drain plug at the bottom of radiator, and then
remove radiator cap.
When draining all of engine coolant in the system, open
water drain plugs on cylinder block. Refer to EM-253, "
DIS-
ASSEMBLY" .
4. Remove reservoir tank as necessary, and drain engine coolant
and clean reservoir tank before installing.
5. Check drained engine coolant for contaminants such as rust, corrosion or discoloration. If contaminated,
flush the engine cooling system. Refer to CO-42, "
FLUSHING COOLING SYSTEM" .
REFILLING ENGINE COOLANT
1. Install reservoir tank if removed, and radiator drain plug.
SMA412B
Testing pressure: 157 kPa (1.6 kg/cm2 , 23 psi)
PBIC5121J
1 : Radiator drain plug hole
2 : Front engine undercover
: Engine front
PBIC3395E
ENGINE COOLANT
CO-41
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CAUTION:
Be sure to clean radiator drain plug and install with new O-ring.
If water drain plugs on cylinder block are removed, close and tighten them. Refer to EM-257,
"ASSEMBLY" .
2. Make sure that each hose clamp has been firmly tightened.
3. Remove air relief plug (1) on heater hose.
4. Fill thermostat housing and reservoir tank to specified level.
Refill engine coolant up to filler neck of thermostat housing.
Pour engine coolant through engine coolant filler neck slowly of less than 2 (2-1/8 US qt, 1-3/4
Imp qt) a minute to allow air in system to escape.
Use Genuine NISSAN Long Life Antifreeze/Coolant or equivalent mixed with water (distilled or
demineralized). Refer to MA-12, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
When engine coolant overflows air relief hole on heater hose,
install air relief plug.
5. Install radiator cap.
6. Warm up until opening thermostat. Standard for warming-up time is approximately 10 minutes at 3,000
rpm.
Make sure thermostat opening condition by touching radiator hose (lower) to see a flow of warm water.
CAUTION:
Watch water temperature gauge so as not to overheat engine.
7. Stop engine and cool down to less than approximately 50°C (122°F).
Cool down using a fan to reduce the time.
If necessary, refill engine coolant up to filler neck of thermostat housing.
8. Refill reservoir tank to “MAX” level line with engine coolant.
9. Repeat steps 4 through 7 two or more times with radiator cap installed until engine coolant level no longer
drops.
10. Check cooling system for leaks with engine running.Radiator drain plug:
: 1.2 N·m (0.12 kg-m, 11 in-lb)
: Engine front
PBIC3394E
Engine coolant capacity
(With reservoir tank at “MAX” level):
Approx. 10.4 (11 US qt, 9-1/8 Imp qt)
Reservoir tank engine coolant capacity
(At “MAX” level):
0.8 (7/8 US qt, 3/4 lmp qt)
Air relief plug:
: 1.2 N·m (0.12 kg-m, 11 in-lb)
SMA412B
CO-42
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ENGINE COOLANT
Revision: 2007 April2007 M35/M45
11. Warm up engine, and check for sound of engine coolant flow while running engine from idle up to 3,000
rpm with heater temperature controller set at several position between “COOL” and “WARM”.
Sound may be noticeable at heater unit.
12. Repeat step 11 three times.
13. If sound is heard, bleed air from cooling system by repeating steps 4 through 7 until engine coolant level
no longer drops.
FLUSHING COOLING SYSTEM
1. Install reservoir tank, and radiator drain plug.
CAUTION:
Be sure to clean drain plug and install with new O-ring.
If water drain plugs on cylinder block are removed, close and tighten them. Refer to EM-257,
"ASSEMBLY" .
2. Remove air relief plug (1) on heater hose.
3. Fill thermostat housing with water until water spills from the air relief hole, then close air relief plug. Fill
thermostat housing and reservoir tank with water and reinstall radiator cap.
4. Run engine and warm it up to normal operating temperature.
5. Rev engine two or three times under no-load.
6. Stop engine and wait until it cools down.
7. Drain water from the system. Refer to CO-40, "
DRAINING ENGINE COOLANT" .
8. Repeat steps 1 through 7 until clear water begins to drain from radiator.Radiator drain plug:
: 1.2 N·m (0.12 kg-m, 11 in-lb)
: Engine front
PBIC3394E
Air relief plug:
: 1.2 N·m (0.12 kg-m, 11 in-lb)
RADIATOR
CO-43
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Revision: 2007 April2007 M35/M45
RADIATORPFP:21400
ComponentsNBS004RG
Refer to GI-11, "Components" for symbols in the figure.
Removal and InstallationNBS004RH
WARNING:
Do not remove radiator cap when engine is hot. Serious burns could occur from high-pressure engine
coolant escaping from thermostat housing. Wrap a thick cloth around radiator cap. Slowly turn it a
quarter of a turn to release built-up pressure. Carefully remove radiator cap by turning it all the way.
REMOVAL
1. Remove the following parts:
Front engine undercover (power tool).
Engine room cover (RH and LH). Refer to EM-173, "ENGINE ROOM COVER" .
Air duct (inlet) and air cleaner case assembly. Refer to EM-177, "AIR CLEANER AND AIR DUCT" .
2. Remove front grille and front grille support. Refer to EI-16, "
FRONT GRILLE" .
3. Drain engine coolant from radiator. Refer to CO-40, "
ENGINE COOLANT" .
1. Reservoir tank cap 2. Reservoir tank 3. Reservoir tank bracket
4. Reservoir tank hose 5. Radiator hose (upper) 6. Air guide
7. Mount bracket (RH) 8. Mounting rubber (upper) 9. A/C condenser
10. Mount bracket (LH) 11. Radiator 12. Mounting rubber (lower)
13. A/T fluid cooler hose 14. A/T fluid cooler hose 15. O-ring
16. Drain plug 17. Radiator hose (lower) 18. Cooling fan assembly
A. To thermostat housing B. To water suction pipe C. To transmission
PBIC4718E
THERMOSTAT AND WATER CONTROL VALVE
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Revision: 2007 April2007 M35/M45
THERMOSTAT AND WATER CONTROL VALVEPFP:21200
ComponentsNBS004RR
Refer to GI-11, "Components" for symbols in the figure.
Removal and InstallationNBS004RS
REMOVAL
1. Remove engine room cover (RH and LH). Refer to EM-173, "ENGINE ROOM COVER" .
2. Remove engine cover with power tool. Refer to EM-179, "
INTAKE MANIFOLD" .
3. Remove air duct (inlet). Refer to EM-177, "
AIR CLEANER AND AIR DUCT" .
4. Drain engine coolant from drain plugs on radiator and both side of cylinder block. Refer to CO-40, "
Chang-
ing Engine Coolant" and EM-253, "DISASSEMBLY" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
1. Water connector 2. O-ring 3. Rubber ring
4. Heater hose 5. Water control valve 6. Water outlet
7. Gasket 8. O-ring 9. Water outlet pipe
10. Thermostat housing 11. Radiator cap 12. Radiator hose (upper)
13. Thermostat 14. Rubber ring 15. Water inlet
16. Water suction hose 17. Water suction pipe 18. Radiator hose (lower)
19. Gasket 20. O-ring 21. Heater pipe
22. Heater hose
A. To radiator B. To intake manifold adapter C. To cylinder block
D. To cylinder head (right bank) E. To cylinder head (left bank) F. To heater core
PBIC3306E
CO-56
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THERMOSTAT AND WATER CONTROL VALVE
Revision: 2007 April2007 M35/M45
5. Disconnect water suction hose from water inlet.
6. Remove water inlet and thermostat.
CAUTION:
Do not disassemble thermostat.
7. Remove intake manifolds (upper and lower). Refer to EM-179, "
INTAKE MANIFOLD" .
8. Disconnect radiator hose (upper) from thermostat housing.
9. Disconnect heater hoses from water outlet and heater pipe.
10. Remove thermostat housing, water outlet pipe, water connector, water control valve, water outlet and
heater pipe.
CAUTION:
Do not disassemble water control valve.
INSPECTION AFTER REMOVAL
Make sure that valves both in thermostat and water control valve are completely closing at normal tempar-
ature.
Place a thread so that it is caught in the valves of the thermostat
and water control valve. Immerse fully in a container filled with
water. Heat while stirring. (The example in the figure shows ther-
mostat.)
The valve opening temperature is the temperature at which the
valve opens and falls from the thread.
Continue heating. Check the maximum valve lift.
NOTE:
The maximum valve lift standard temperature for water control
valve is the reference value.
After checking the maximum valve lift, lower the water tempera-
ture and check the valve closing temperature.
Standard values:
If the malfunctioning condition, when closing valve at normal temperature, or measured values are out of
the standard, replace thermostat and/or water control valve.
INSTALLATION
Note the following, and install in the reverse order of removal.
CAUTION:
Be careful not to spill engine coolant over engine room. Use rag to absorb engine coolant.
Thermostat and Water Control Valve
Install thermostat and water control valve with the whole circum-
ference of each flange part fit securely inside rubber ring. (The
example in the figure shows thermostat.)
SLC252B
Thermostat Water control valve
Valve opening temperature 80 - 84°C (176 - 183°F) 93.5 - 96.5°C (200 - 206°F)
Maximum valve liftMore than 10 mm/95°C
(0.39 in/203°F)More than 8 mm/108°C
(0.315 in/226°F)
Valve closing temperature 77°C (171°F) 90°C (194°F)
PBIC0157E
THERMOSTAT AND WATER CONTROL VALVE
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Revision: 2007 April2007 M35/M45
Install thermostat with jiggle valve facing upwards. (The position
deviation may be within the range of ±10 degrees)
Install water control valve with the up-mark facing up and the
frame center part facing upwards. (The position deviation may
be within the range of ±10 degrees)
Water Outlet Pipe and Heater Pipe
First apply a neutral detergent to 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 engine coolant using radiator cap tester adapter (commercial service tool) and radiator
cap tester (commercial service tool). Refer to CO-40, "
LEAK CHECK" .
Start and warm up engine. Visually check if there is no leaks of engine coolant.
PBIC0158E