2007 INFINITI M35 engine overheat

ATC-104
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high.The pressure returns to nor-
mal soon after water is
splashed on condenser.Excessive refrigerant charge
in refrigeration cycle.Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient.Insufficient condenser cooling
performance.
↓
1. Condenser fins are clogged.
2. Improper fan rotation of
cooling fan.

Clean condenser.

Check and repair cooling fan
as necessary.

Low-pressure pipe is not
cold.

When compressor is
stopped high-pressure
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after.Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.).
↓
Air in refrigeration cycle.Evacuate repeatedly and
recharge system.
Engine tends to overheat.Engine cooling systems mal-
function.Check and repair each engine
cooling system.

An area of the low-pres-
sure pipe is colder than
areas near the evaporator
outlet.

Low-pressure pipe is
sometimes covered with
frost.

Excessive liquid refrigerant
on low-pressure side.

Excessive refrigerant dis-
charge flow.

Expansion valve is open a
little compared with the
specification.
↓
Improper expansion valve
adjustment.Replace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.

Check and repair or replace
malfunctioning parts.

Check lubricant for contami-
nation.
AC360A

CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
C
D
E
F
G
H
I
J
K
L
M
SECTION CO
A
CO
Revision: 2007 April2007 M35/M45
ENGINE COOLING SYSTEM
VQ35DE
PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Liquid Gasket .................................. 3
REMOVAL OF LIQUID GASKET SEALING .......... 3
LIQUID GASKET APPLICATION PROCEDURE ..... 3
PREPARATION ........................................................... 5
Special Service Tools ............................................... 5
Commercial Service Tools ........................................ 6
OVERHEATING CAUSE ANALYSIS .......................... 7
Troubleshooting Chart .............................................. 7
COOLING SYSTEM .................................................... 9
Cooling Circuit .......................................................... 9
System Chart ......................................................... 10
ENGINE COOLANT ...................................................11
Inspection ................................................................ 11
LEVEL CHECK .................................................... 11
LEAK CHECK ...................................................... 11
Changing Engine Coolant ....................................... 11
DRAINING ENGINE COOLANT .......................... 11
REFILLING ENGINE COOLANT ........................ 12
FLUSHING COOLING SYSTEM ......................... 13
RADIATOR ................................................................ 14
Components ........................................................... 14
Removal and Installation ........................................ 14
REMOVAL ........................................................... 14
INSTALLATION ................................................... 16
INSPECTION AFTER INSTALLATION ............... 16
Checking Radiator Cap .......................................... 16
Checking Radiator .................................................. 16
RADIATOR (ALUMINUM TYPE) .............................. 18
Components ........................................................... 18
Disassembly and Assembly ................................... 18
PREPARATION ................................................... 18
DISASSEMBLY ................................................... 18
ASSEMBLY ......................................................... 19
INSPECTION ...................................................... 21COOLING FAN .......................................................... 22
Components ........................................................... 22
Removal and Installation ........................................ 22
REMOVAL ........................................................... 22
INSTALLATION ................................................... 22
INSPECTION AFTER INSTALLATION ................ 22
Disassembly and Assembly .................................... 23
DISASSEMBLY ................................................... 23
INSPECTION AFTER DISASSEMBLY ................ 23
ASSEMBLY ......................................................... 23
WATER PUMP .......................................................... 24
Components ........................................................... 24
Removal and Installation ........................................ 24
REMOVAL ........................................................... 24
INSPECTION AFTER REMOVAL ....................... 26
INSTALLATION ................................................... 26
INSPECTION AFTER INSTALLATION ................ 28
WATER INLET AND THERMOSTAT ASSEMBLY .... 29
Components ........................................................... 29
Removal and Installation ........................................ 29
REMOVAL ........................................................... 29
INSPECTION AFTER REMOVAL ....................... 30
INSTALLATION ................................................... 30
INSPECTION AFTER INSTALLATION ................ 30
WATER OUTLET AND WATER PIPING ................... 31
Components ........................................................... 31
Removal and Installation ........................................ 31
REMOVAL ........................................................... 31
INSTALLATION ................................................... 32
INSPECTION AFTER INSTALLATION ................ 32
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 33
Standard and Limit .................................................. 33
ENGINE COOLANT CAPACITY (APPROXI-
MATE) .................................................................. 33
RADIATOR .......................................................... 33
THERMOSTAT .................................................... 33

CO-2Revision: 2007 April2007 M35/M45
VK45DE
PRECAUTIONS ......................................................... 34
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................. 34
PREPARATION ......................................................... 35
Special Service Tools ............................................. 35
Commercial Service Tools ...................................... 35
OVERHEATING CAUSE ANALYSIS ........................ 36
Troubleshooting Chart ............................................ 36
COOLING SYSTEM .................................................. 38
Cooling Circuit ........................................................ 38
System Chart .......................................................... 39
ENGINE COOLANT .................................................. 40
Inspection ............................................................... 40
LEVEL CHECK .................................................... 40
LEAK CHECK ...................................................... 40
Changing Engine Coolant ....................................... 40
DRAINING ENGINE COOLANT .......................... 40
REFILLING ENGINE COOLANT ......................... 40
FLUSHING COOLING SYSTEM ......................... 42
RADIATOR ................................................................ 43
Components ........................................................... 43
Removal and Installation ........................................ 43
REMOVAL ........................................................... 43
INSTALLATION .................................................... 44
INSPECTION AFTER INSTALLATION ................ 45
Checking Radiator Cap .......................................... 45
Checking Radiator .................................................. 45
RADIATOR (ALUMINUM TYPE) ............................... 47
Components ........................................................... 47
Disassembly and Assembly .................................... 47
PREPARATION ................................................... 47
DISASSEMBLY ................................................... 47
ASSEMBLY ......................................................... 48
INSPECTION ....................................................... 50COOLING FAN .......................................................... 51
Components ............................................................ 51
Removal and Installation ......................................... 51
REMOVAL ............................................................ 51
INSTALLATION .................................................... 51
INSPECTION AFTER INSTALLATION ................ 51
Disassembly and Assembly .................................... 52
DISASSEMBLY .................................................... 52
INSPECTION AFTER DISASSEMBLY ................ 52
ASSEMBLY .......................................................... 52
WATER PUMP ........................................................... 53
Components ............................................................ 53
Removal and Installation ......................................... 53
REMOVAL ............................................................ 53
INSPECTION AFTER REMOVAL ........................ 54
INSTALLATION .................................................... 54
INSPECTION AFTER INSTALLATION ................ 54
THERMOSTAT AND WATER CONTROL VALVE ..... 55
Components ............................................................ 55
Removal and Installation ......................................... 55
REMOVAL ............................................................ 55
INSPECTION AFTER REMOVAL ........................ 56
INSTALLATION .................................................... 56
INSPECTION AFTER INSTALLATION ................ 57
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 58
Standard and Limit .................................................. 58
ENGINE COOLANT CAPACITY (APPROXI-
MATE) .................................................................. 58
RADIATOR ........................................................... 58
THERMOSTAT ..................................................... 58
WATER CONTROL VALVE .................................. 58

OVERHEATING CAUSE ANALYSIS
CO-7
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
CO
Revision: 2007 April2007 M35/M45
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartNBS004QN
Symptom Check items
Cooling sys-
tem parts
malfunctionPoor heat transferWater pump malfunction Worn or loose drive belt
— Thermostat 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-8
[VQ35DE]
OVERHEATING CAUSE ANALYSIS
Revision: 2007 April2007 M35/M45
Except cool-
ing system
parts mal-
function— Overload on engineAbusive drivingHigh engine rpm under no
load
Driving in low gear for
extended time
Driving at extremely high
speed
Powertrain system mal-
function
— Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flowBlocked bumper —
— Blocked radiator grilleInstalled car brassiere
Mud contamination or
paper clogging
Blocked radiator —
Blocked condenser
Blocked air flow
Installed large fog lamp Symptom Check items

CO-12
[VQ35DE]
ENGINE COOLANT
Revision: 2007 April2007 M35/M45
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-13, "
FLUSHING COOLING SYSTEM" .
REFILLING ENGINE COOLANT
1. Install reservoir tank if removed, 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-129,
"ASSEMBLY" .
2. Make sure that each hose clamp has been firmly tightened.
3. Remove air relief plug on heater hose.
4. Fill radiator, and reservoir tank if removed, to specified level.

Pour engine coolant through engine coolant filler neck
slowly of less than 2 (2-1/8 US qt, 1-3/4 lmp 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 LUBRI-
CANTS" .

When engine coolant overflows air relief hole on heater hose,
install air relief plug with new O-ring.
5. Install radiator cap.
6. Warm up engine 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.Radiator drain plug:
: 1.2 N·m (0.12 kg-m, 11 in-lb)
SBIA0445E
Engine coolant capacity
(With reservoir tank at “MAX” level)
: Approximately 8.9 (9-3/8 US qt, 7-7/8 lmp qt)
SMA182B
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-36
[VK45DE]
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

OVERHEATING CAUSE ANALYSIS
CO-37
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
CO
Revision: 2007 April2007 M35/M45
Except cool-
ing system
parts mal-
function— Overload on engineAbusive drivingHigh engine rpm under no
load
Driving in low gear for
extended time
Driving at extremely high
speed
Powertrain system mal-
function
— Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flowBlocked bumper —
— Blocked radiator grilleInstalled car brassiere
Mud contamination or
paper clogging
Blocked radiator —
Blocked condenser
Blocked air flow
Installed large fog lamp Symptom Check items