CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
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SECTION CO
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Revision: 2006 November2007 350Z
ENGINE COOLING SYSTEM
PRECAUTIONS .......................................................... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 2
Precautions for Battery Service ................................ 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 ........................................ 5
OVERHEATING CAUSE ANALYSIS .......................... 6
Troubleshooting Chart .............................................. 6
COOLING SYSTEM .................................................... 8
Cooling Circuit .......................................................... 8
System Chart ........................................................... 9
ENGINE COOLANT .................................................. 10
Inspection ............................................................... 10
LEVEL CHECK ................................................... 10
LEAK CHECK ..................................................... 10
Changing Engine Coolant ...................................... 10
DRAINING ENGINE COOLANT ......................... 10
REFILLING ENGINE COOLANT ......................... 11
FLUSHING COOLING SYSTEM ......................... 12
RADIATOR ................................................................ 13
Removal and Installation ........................................ 13
REMOVAL ........................................................... 13
INSTALLATION ................................................... 15
INSPECTION AFTER INSTALLATION ............... 15
Checking Radiator Cap .......................................... 15
Checking Radiator .................................................. 15
RADIATOR (ALUMINUM TYPE) .............................. 17
Disassembly and Assembly ................................... 17
PREPARATION ................................................... 17
DISASSEMBLY ................................................... 17
ASSEMBLY ......................................................... 18
INSPECTION ...................................................... 20COOLING FAN .......................................................... 21
Removal and Installation ........................................ 21
REMOVAL ........................................................... 21
INSTALLATION ................................................... 21
Disassembly and Assembly .................................... 22
DISASSEMBLY ................................................... 22
INSPECTION AFTER DISASSEMBLY ................ 22
ASSEMBLY ......................................................... 22
WATER PUMP .......................................................... 23
Removal and Installation ........................................ 23
REMOVAL ........................................................... 23
INSPECTION AFTER REMOVAL ....................... 24
INSTALLATION ................................................... 24
INSPECTION AFTER INSTALLATION ................ 25
WATER INLET AND THERMOSTAT ASSEMBLY .... 26
Removal and Installation ........................................ 26
REMOVAL ........................................................... 26
INSPECTION AFTER REMOVAL ....................... 26
INSTALLATION ................................................... 27
INSPECTION AFTER INSTALLATION ................ 27
WATER OUTLET AND WATER PIPING ................... 28
Removal and Installation ........................................ 28
REMOVAL ........................................................... 28
INSTALLATION ................................................... 29
INSPECTION AFTER INSTALLATION ................ 29
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 30
Standard and Limit .................................................. 30
ENGINE COOLANT CAPACITY (APPROXI-
MATE) .................................................................. 30
RADIATOR .......................................................... 30
THERMOSTAT .................................................... 30
CO-2
PRECAUTIONS
Revision: 2006 November2007 350Z
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
NBS0001M
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Battery ServiceNBS0001N
Before disconnecting the battery, lower both the driver and passenger windows. This will prevent any interfer-
ence between the window edge and the vehicle when the door is opened/closed. During normal operation, the
window slightly raises and lowers automatically to prevent any window to vehicle interference. The automatic
window function will not work with the battery disconnected.
Precautions for Liquid GasketNBS0001O
REMOVAL OF LIQUID GASKET SEALING
After removing mounting bolts and nuts, separate the mating
surface using seal cutter (SST) and remove old liquid gasket
sealing.
CAUTION:
Be careful not to damage the mating surfaces.
Tap seal cutter to insert it, and then slide it by tapping on the
side as shown in the figure.
In areas where seal cutter (SST) is difficult to use, use plastic
hammer to lightly tap the parts, to remove it.
CAUTION:
If for some unavoidable reason tool such as screwdriver is
used, be careful not to damage the mating surfaces.
LIQUID GASKET APPLICATION PROCEDURE
1. Using scraper, remove old liquid gasket adhering to the liquid
gasket application surface and the mating surface.
Remove liquid gasket completely from the groove of the liquid
gasket application surface, mounting bolts, and bolt holes.
2. Wipe the liquid gasket application surface and the mating sur-
face with white gasoline (lighting and heating use) to remove
adhering moisture, grease and foreign materials.
PBIC0002E
PBIC0003E
CO-6
OVERHEATING CAUSE ANALYSIS
Revision: 2006 November2007 350Z
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartNBS0001R
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 viscosity —
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-10
ENGINE COOLANT
Revision: 2006 November2007 350Z
ENGINE COOLANTPFP:KQ100
InspectionNBS0001U
LEVEL CHECK
Check if the reservoir tank engine coolant level is within the
“MIN” to “MAX” range 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) and radiator cap
tester adapter (commercial service tool) (A).
WARNING:
Do not remove radiator cap when engine is hot. Serious
burns could occur from high-pressure engine coolant
escaping from radiator.
CAUTION:
Higher test pressure than specified may cause radiator
damage.
NOTE:
In a case that engine coolant decreases, replenish radiator with engine coolant.
If anything is found, repair or replace damaged parts.
Changing Engine CoolantNBS0001V
WARNING:
To avoid being scalded, do not change engine coolant when engine is hot.
Wrap a thick cloth around cap and carefully remove cap. First, turn cap a quarter of a turn to
release built-up pressure. Then turn cap all the way.
CAUTION:
Be careful not to allow engine coolant to contact drive belts.
DRAINING ENGINE COOLANT
1. Remove undercover with power tool.
2. Open radiator drain plug at the bottom of radiator, and then
remove radiator cap.
When drain all of engine coolant in the system, open water drain plugs on engine cylinder block.
Refer to EM-108, "
DISASSEMBLY" .
SMA412B
Testing pressure
: 157 kPa (1.6 kg/cm
2 , 23 psi)
PBIC5072E
PBIC0893E
RADIATOR
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RADIATORPFP:21400
Removal and InstallationNBS0001W
Refer to GI-11, "Components" for symbol marks in the figure.
WARNING:
Do not remove radiator cap when engine is hot. Serious burns could occur from high-pressure engine
coolant escaping from radiator. Wrap a thick cloth around the 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 undercover with power tool.
2. Drain engine coolant from radiator. Refer to CO-10, "
Changing Engine Coolant" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
3. Remove air duct and air cleaner case assembly. Refer toEM-15, "
AIR CLEANER AND AIR DUCT" .
4. Remove bracket mounting bolt for anchoring A/C piping from vehicle left side, so that A/C piping can be
moved.
1. Reservoir tank hose 2. Reservoir tank cap 3. Reservoir tank hose
4. Radiator hose (upper) 5. Upper mount bracket 6. Mounting rubber (upper)
7. Cover 8. Radiator 9. Mounting rubber (lower)
10. Radiator drain plug 11. O-ring 12. A/T fluid cooler hose (A/T models)
13. Radiator hose (lower) 14. Radiator cooling fan assembly 15. Reservoir tank
A. To water outlet B. To A/T fluid cooler tube (A/T models) C. To water inlet
D. To water outlet
PBIC5031E
CO-14
RADIATOR
Revision: 2006 November2007 350Z
5. Remove reservoir tank.
6. Removal radiator hoses (upper and lower) and reservoir tank hose.
CAUTION:
Be careful not to allow engine coolant to contact drive belts.
7. Remove radiator cooling fan assembly. Refer to CO-21, "
COOLING FAN" .
8. Disconnect A/T fluid cooler hoses. (A/T models)
Install blind plug to avoid leakage of A/T fluid.
9. Remove cover, and then two A/C condenser mounting bolts
located in upper part of radiator.
10. Rotate two radiator upper mount brackets 90 degrees in the
direction as shown in the figure, and remove them.
11. Remove radiator as follows:
CAUTION:
Do not damage or scratch A/C condenser and radiator core when removing.
a. With lifting and pulling radiator in a rear direction, disassemble
lower mount from radiator core support center.
CAUTION:
Because A/C condenser is onto the front-lower portion of
radiator, moving to rear direction should be at minimum.
b. Lift A/C condenser up and remove radiator after disengaging the
fitting as front-bottom surface.
CAUTION:
Lifting A/C condenser should be minimum to prevent a load
to A/C piping.
c. After removing radiator, put A/C condenser on radiator core sup-
port center to prevent a load to A/C piping, and temporarily fix it
with rope or similar means.
PBIC1053E
PBIC1052E
PBIC1936E
PBIC1054E
COOLING FAN
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Revision: 2006 November2007 350Z
COOLING FANPFP:21140
Removal and InstallationNBS00020
REMOVAL
1. Remove engine cover with power tool. Refer to EM-17, "INTAKE MANIFOLD COLLECTOR" .
2. Drain engine coolant from radiator. Refer to CO-10, "
Changing Engine Coolant" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
3. Remove air cleaner case assembly (RH, LH). Refer to EM-15, "
AIR CLEANER AND AIR DUCT" .
4. Remove reservoir tank. Refer to CO-13, "
RADIATOR" .
5. Disconnect radiator hose (upper) at radiator side. Refer to CO-13, "
RADIATOR" .
6. Disconnect fan motor harness connectors at the right-lower por-
tion of fan shroud.
7. Remove mounting bolts to lift up and radiator cooling fan assembly.
CAUTION:
Be careful not to damage or scratch on radiator core.
INSTALLATION
Installation is the reverse order of removal.
NOTE:
Cooling fans are controlled by ECM. For details, refer to EC-543, "
DTC P1217 ENGINE OVER TEMPERA-
TURE" .
1. Cooling fan (RH) 2. Cooling fan (LH) 3. Fan shroud
4. Fan motor
PBIC2609E
PBIC1935E
WATER PUMP
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WAT E R P U MPPFP:21020
Removal and InstallationNBS00022
Refer to GI-11, "Components" for symbol marks in the figure.
CAUTION:
When removing water pump assembly, be careful not to get engine coolant on drive belt.
Water pump cannot be disassembled and should be replaced as a unit.
After installing water pump, connect hose and clamp securely, then check for leaks using radiator
cap tester (commercial service tool) and radiator cap tester adapter (commercial service tool).
REMOVAL
1. Remove front timing chain case. Refer to EM-44, "FRONT TIMING CHAIN CASE" .
2. Remove timing chain tensioner (primary) as follows:
a. Remove lower mounting bolt (1).
b. Loosen upper mounting bolt (2) slowly, and then turn chain ten-
sioner (primary) (3) on the upper mounting bolt so that plunger
(4) is fully expanded.
NOTE:
Even if plunger is fully expanded, it is not dropped from the body
of timing chain tensioner (primary).
c. Remove upper mounting bolt, and then remove timing chain tensioner (primary).
3. Remove water pump as follows:
a. Remove three water pump mounting bolts. Secure a gap between water pump gear and timing chain, by
turning crankshaft counterclockwise until timing chain looseness on water pump sprocket becomes maxi-
mum.
1. Timing chain tensioner (primary) 2. Water pump 3. O-ring
4. O- ring
A. Identify with yellow paint mark B.Identify with light blue paint mark
Apply engine coolant
PBIC5030E
PBIC4938E