Infiniti F50. Manual - part 284

OVERHEATING CAUSE ANALYSIS

CO-5

C

D

E

F

G

H

I

J

K

L

M

A

CO

OVERHEATING CAUSE ANALYSIS

PFP:00012

Troubleshooting Chart

EBS00257

Symptom

Check items

Cooling sys-
tem parts 
malfunction

Poor heat transfer

Water pump malfunction

Worn or loose drive belt

—

Thermostat stuck closed

—

Damaged fins

Dust contamination or 
paper 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

—

—

—

Improper engine coolant 
mixture ratio

—

—

—

Poor engine coolant quality

—

Engine coolant density

—

Insufficient engine coolant

Engine coolant leaks

Cooling hose

Loose clamp

Cracked hose

Water pump

Poor sealing

Radiator cap

Loose

Poor sealing

Radiator

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

Cracked radiator tank

Cracked radiator core

Reservoir tank

Cracked reservoir tank

Overflowing reservoir tank

Exhaust gas leaks into 
cooling system

Cylinder head deterioration

Cylinder head gasket dete-
rioration

CO-6

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 
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

COOLING SYSTEM

CO-7

C

D

E

F

G

H

I

J

K

L

M

A

CO

COOLING SYSTEM

PFP:21020

Cooling Circuit

EBS001KG

SBIA0340E

CO-8

COOLING SYSTEM

System Drawing

EBS00KMZ

PBIC0160E