Infiniti M35/M45 Y50. Manual — part 349

OVERHEATING CAUSE ANALYSIS

CO-37

[VK45DE]

C

D

E

F

G

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A

CO

Except cool-
ing system
parts mal-
function

—

Overload on engine

Abusive driving

High 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
flow

Blocked bumper

—

—

Blocked radiator grille

Installed car brassiere

Mud contamination or
paper clogging

Blocked radiator

—

Blocked condenser

Blocked air flow

Installed large fog lamp

Symptom

Check items

CO-38

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COOLING SYSTEM

COOLING SYSTEM

PFP:21020

Cooling Circuit

NBS004RC

PBIC3839E

COOLING SYSTEM

CO-39

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D

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System Chart

NBS004RD

PBIC3838E

CO-40

[VK45DE]

ENGINE COOLANT

ENGINE COOLANT

PFP:KQ100

Inspection

NBS004RE

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 Coolant

NBS004RF

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/cm

2

, 23 psi)

PBIC5121J

1

: Radiator drain plug hole

2

: Front engine undercover

: Engine front

PBIC3395E