Infiniti Q45 (FY33). Manual - part 246
MAIN 12 CAUSES OF OVERHEATING
Engine
Step
Inspection item
Equipment
Standard
Reference page
OFF
1
I
Blocked radiator
I
Blocked condenser
I
Blocked radiator grille
I
Blocked bumper
I
Visual
No blocking
—
2
I
Coolant mixture
I
Coolant tester
50 - 50% coolant mixture
See “RECOMMENDED
FLUIDS AND LUBRI-
CANTS” in MA section
3
I
Coolant level
I
Visual
Coolant up to MAX level
in reservoir tank and
radiator filler neck
See “Changing Engine
Coolant”, “ENGINE MAIN-
TENANCE” in MA section
4
I
Radiator cap
I
Pressure tester
98 - 118 kPa
(1.0 - 1.2 kg/cm
2
, 14 - 17
psi)
59 - 118 kPa
(0.6 - 1.2 kg/cm
2
, 9 - 17
psi) (Limit)
See “System Check”
“ENGINE COOLING SYS-
TEM” in LC section
ON*
2
5
I
Coolant leaks
I
Visual
No leaks
See “System Check”
“ENGINE COOLING SYS-
TEM” in LC section
ON*
2
6
I
Thermostat
I
Touch the upper and
lower radiator hoses
Both hoses should be hot
See “Thermostat” and
“Radiator”, “ENGINE
COOLING SYSTEM” in
LC section
ON*
1
7
I
Cooling fan
I
CONSULT-II
Operating
See “TROUBLE DIAGNO-
SIS FOR OVERHEAT”
(EC-503)
OFF
8
I
Combustion gas leak
I
Color checker
chemical tester
4 Gas analyzer
Negative
—
ON*
3
9
I
Coolant temperature
gauge
I
Visual
Gauge less than 3/4
when driving
—
I
Coolant overflow to res-
ervoir tank
I
Visual
No overflow during driving
and idling
See “Changing Engine
Coolant”, “ENGINE MAIN-
TENANCE” in MA section
OFF*
4
10
I
Coolant return from res-
ervoir tank to radiator
I
Visual
Should be initial level in
reservoir tank
See “ENGINE MAINTE-
NANCE” in MA section
OFF
11
I
Cylinder head
I
Straight gauge feeler
gauge
0.1 mm (0.004 in) Maxi-
mum distortion (warping)
See “Inspection”, “CYLIN-
DER HEAD” in EM sec-
tion
12
I
Cylinder block and pis-
tons
I
Visual
No scuffing on cylinder
walls or piston
See “Inspection”, “CYLIN-
DER BLOCK” in EM sec-
tion
*1: Turn the ignition switch ON.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to “OVERHEATING CAUSE ANALYSIS” in LC section.
GI
MA
EM
LC
FE
AT
PD
FA
RA
BR
ST
RS
BT
HA
EL
IDX
TROUBLE DIAGNOSIS FOR OVERHEAT
Overheat (Cont’d)
EC-513