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Nissan Pathfinder (2012 year). Manual - part 126

PREPARATION

CO-5

< PREPARATION >

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PREPARATION

Special Service Tool

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The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.

Tool number
(Kent-Moore No.)
Tool name

Description

KV10111100
(J-37228)
Seal cutter

Removing chain tensioner cover and water
pump cover

WS39930000
( — )
Tube presser

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) diameter
b: 31.4 (1.236) diameter
c: 41.3 (1.626) diameter

Unit: mm (in)

KV991J0070
(J-45695)
Coolant refill tool

Filling cooling system

KV991J0010
(J-23688)
Engine coolant refractometer

Checking concentration of ethylene glycol in
engine coolant

—

(J-24460-92)
Radiator Pressure Test Adapter

Pressure testing of the pressurized cooling
system overflow tank

NT046

S-NT052

S-NT564

LMA053

WBIA0539E

AWBIA0891ZZ

August 2012

2012 Pathfinder

CO-6

< PREPARATION >

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PREPARATION

Commercial Service Tool

INFOID:0000000007357903

Tool name

Description

Power tool

Loosening nuts, screws and bolts

Radiator cap tester

Checking radiator and radiator cap

PIIB1407E

PBIC1982E

August 2012

2012 Pathfinder

COOLING SYSTEM

CO-7

< SYSTEM DESCRIPTION >

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SYSTEM DESCRIPTION

COOLING SYSTEM

Cooling Circuit

INFOID:0000000007357904

WBIA0641E

Cylinder block (RH)

Oil cooler

Cylinder head (RH)

Water pump

Radiator

Water inlet

Thermostat

Cylinder head (LH)

Heater pump

10. Cylinder block (LH)

August 2012

2012 Pathfinder

CO-8

< SYSTEM DESCRIPTION >

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COOLING SYSTEM

Schematic

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WBIA0565E

August 2012

2012 Pathfinder

OVERHEATING CAUSE ANALYSIS

CO-9

< SYSTEM DESCRIPTION >

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OVERHEATING CAUSE ANALYSIS

Troubleshooting Chart

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Symptom

Check items

Cooling sys-
tem parts
malfunction

Poor heat transfer

Water pump malfunction

Worn or loose drive belt

—

Coolant circulation

Thermostat stuck closed

Damaged fins

Dust contamination or pa-
per clogging

Physical damage

Clogged radiator cooling
tube

Excess foreign material
(rust, dirt, sand, etc.)

Reduced air flow

Cooling fan does not oper-
ate

Fan assembly

—

High resistance to fan rota-
tion

Damaged fan blades

Damaged radiator shroud

—

Radiator shroud

—

Improper engine coolant
mixture ratio

—

Engine coolant viscosity

—

Poor engine coolant quality

—

Insufficient engine coolant

Engine coolant leaks

Cooling hose

Loose clamp

Cracked hose

Heater pump

Physical damage

Water pump

Poor sealing

Radiator or reservoir cap

Loose

Poor sealing

O-ring for damage, deterio-
ration or improper fitting

Radiator

Cracked radiator tank

Cracked radiator core

Reservoir tank

Cracked reservoir tank

Overflowing reservoir tank

Exhaust gas leaks into cool-
ing system

Cylinder head deterioration

Cylinder head gasket deteri-
oration

August 2012

2012 Pathfinder

CO-10

< SYSTEM DESCRIPTION >

[VQ40DE]

OVERHEATING CAUSE ANALYSIS

Except cool-
ing system
parts mal-
function

—

Overload on engine

Abusive driving

High engine rpm under no
load

Driving in low gear for ex-
tended time

Driving at extremely high
speed

Powertrain system malfunc-
tion

—

Installed improper size
wheels and tires

Dragging brakes

Improper ignition timing

Blocked or restricted air
flow

Blocked bumper

Installed car brassiere

—

Blocked radiator grille

Mud contamination or paper
clogging

Blocked radiator

Blocked condenser

Blocked air flow

Installed large fog lamp

Symptom

Check items

August 2012

2012 Pathfinder

ENGINE COOLANT

CO-11

< PERIODIC MAINTENANCE >

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PERIODIC MAINTENANCE

ENGINE COOLANT

System Inspection

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WARNING:

• Never remove the radiator/reservoir cap when the engine is hot. Serious burns could occur from

high pressure fluid escaping from the radiator or reservoir.

• Wrap a thick cloth around the cap. Slowly push down and turn it a quarter turn to allow built-up pres-

sure to escape. Carefully remove the cap by pushing down and turning it all the way.

CHECKING COOLING SYSTEM HOSES

Check hoses for the following:

• Improper attachment

• Leaks

• Cracks

• Damage

• Loose connections

• Chafing

• Deterioration

CHECKING RESERVOIR LEVEL

• Check if the engine coolant reservoir tank level is within MIN to

MAX when the engine is cool.

• Adjust engine coolant level as necessary.

CHECKING COOLING SYSTEM FOR LEAKS

WARNING:

Never remove the radiator/reservoir cap when the engine is hot. Serious burns could occur from high

pressure 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 (A) and Tool (B).

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

1. Inspect the reservoir cap.

• 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.

NOTE:

Thoroughly wipe out the reservoir filler neck to remove any waxy residue or foreign material.

SMA412B

Tool number

: — (J-24460-92)

Testing pressure

: 137 kPa (1.4 kg/cm

, 20 psi)

AWBIA1467ZZ

August 2012

2012 Pathfinder

CO-12

< PERIODIC MAINTENANCE >

[VQ40DE]

ENGINE COOLANT

2. Pull the negative-pressure valve to open it and check that it

closes completely when released.

• Check that there is no dirt or damage on the valve seat of the

reservoir cap negative-pressure valve.

• Check that there are no abnormalities in the opening and clos-

ing conditions of the negative-pressure valve.

3. Check reservoir cap relief pressure using suitable tool and Tool.

NOTE:

• Apply engine coolant to the cap seal surface.

• 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 deposits of waxy residue or other foreign material are on the black rubber gasket or the

metal retainer.

CHECKING RADIATOR

Check radiator for mud or clogging. If necessary, clean radiator as follows.

CAUTION:

• Be careful not to bend or damage the radiator fins.

• When radiator is cleaned without removal, remove all surrounding parts such as cooling fan, radia-

tor shroud and horns. Then tape the harness and electrical connectors to prevent water from enter-

ing.

1. Spray water to the back side of the radiator core using a side to side motion from the top down.
2. Stop spraying when debris no longer flows from radiator core.
3. Blow air into the back side of radiator core using a side to side motion from the top down.

• Use compressed air lower than 490 kPa (5 kg/cm

, 71 psi) and keep distance more than 30 cm (11.8 in).

4. Continue to blow air until no water sprays out.
5. Check for coolant leaks. Repair as necessary.

Changing Engine Coolant

INFOID:0000000007357908

WARNING:

Do not remove the radiator cap when the engine is hot. Serious burns could occur from high-pressure

engine coolant escaping from the radiator. Wrap a thick cloth around the 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.

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 under cover using power tool.

SMA967B

Tool number

: — (J-33984-A)

Standard: 98 – 118 kPa (1.0 – 1.2 kg/cm

, 14 – 17 psi)

WBIA0570E

August 2012

2012 Pathfinder

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