engine INFINITI QX56 2008 Factory Service Manual

PRECAUTIONSEM-5
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Precaution for Liquid GasketINFOID:0000000001538800
REMOVAL OF LIQUID GASKET SEALING
• After removing the bolts and nuts, separate the mating surface and
remove the old liquid gasket sealing using Tool.
CAUTION:
Do not damage the mating surfaces.
• Tap the seal cutter to insert it (1).
• In areas where the Tool is difficult to use, lightly tap to slide it (2).
LIQUID GASKET APPLICATION PROCEDURE
1. Remove the old liquid gasket adhering to the gasket application surface and the mating surface using suitable tool.
• Remove the liquid gasket completely from the groove of the
liquid gasket application surface, bolts, and bolt holes.
2. Thoroughly clean the mating surfaces and remove adhering moisture, grease and foreign material.
3. Attach the liquid gasket tube to the Tool. Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-15, "
Recommended Chemical Products and Sealants".
4. Apply the liquid gasket without breaks to the specified location with the specified dimensions.
• If there is a groove for the liquid gasket application, apply theliquid gasket to the groove.
• As for the bolt holes, normally apply the liquid gasket inside
the holes. If specified in the procedure, it should also be
applied outside the holes.
• Within five minutes of liquid gasket application, install the mat-
ing component.
• If the liquid gasket protrudes, wipe it off immediately.
• Do not retighten after the installation.
• Wait 30 minutes or more after installation before refilling the engine with engine oil and engine coolant.
CAUTION:
If there are specific instructions in this manual, observe them.
Tool number : KV10111100 (J-37228)
WBIA0566E
PBIC0003E
Tool number : WS39930000 ( — )
WBIA0567E
SEM159F
Revision: March 2010
2008 QX56

EM-10
< FUNCTION DIAGNOSIS >
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
FUNCTION DIAGNOSIS
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting - Engine NoiseINFOID:0000000001538803
AWBIA0149ZZ
Revision: March 2010 2008 QX56

NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTINGEM-11
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Use the Chart Below to Help You
Find the Cause of the SymptomINFOID:0000000001538804
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
1. Timing chain 2. Intake valve3. Exhaust valve
4. Drive belt 5. Water pumpA. VTC noise
B. Tappet noise C. Camshaft bearing noiseD. Valve mechanism
E. Rotation mechanism F. Piston pin noise G. Piston slap noise
H. Main bearing noise I. Connecting rod bearing noise J. Drive belt noise (slipping)
K. Drive belt noise (stick/slipping) L. Water pump noise M. Timing chain and chain tensioner noise
Location of noise Ty p e o f
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Be-
fore
warm-
up After
warm- up When
start- ing When
idling When
racing While
driv- ing
Top of en-
gine
Rocker cov-
er
Cylinder
head Ticking or
clicking
C A — A B — Tappet noise Valve clearance
EM-18
Rattle C A — A B CCamshaft
bearing noiseCamshaft journal clear-
ance
Camshaft runout EM-53EM-53
Crankshaft
pulley
Cylinder
block (Side
of engine)
Oil panSlap or
knock
—A—B B—
Piston pin
noisePiston and piston pin
clearance
Connecting rod bushing
clearance
EM-90
EM-90
Slap or
rap
A——B B A
Piston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsion EM-90EM-90
EM-90
EM-90
Knock A B C B B B
Connecting
rod bearing
noiseConnecting rod bushing
oil clearance (Small
end)
Connecting rod bearing
clearance (Big end)
EM-90EM-90
Knock A B — A B C
Main bearing
noiseMain bearing oil clear-
ance
Crankshaft runout EM-90EM-90
Front of en-
gine
Chain case
cover
Front coverTapping
or ticking
AA—BBB Timing chain
and chain
tensioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operation
EM-45
EM-45
Revision: March 2010
2008 QX56

EM-12
< FUNCTION DIAGNOSIS >
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
A: Closely related B: Related C: Sometimes related —: Not relatedFront of en-
gine
Squeak-
ing or
fizzing
AB—B—C
Drive belts
(Sticking or
slipping)Drive belts deflection
EM-13
Creaking A B A B A B Drive belts
(Slipping)Idler pulley bearing op-
eration
Squall
Creaking AB—BAB Water pump
noiseWater pump operation
CO-20
Rattle — — A — — — VTC VTC lock pin clearanceEM-44
Location of
noise Type of
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Be-
fore
warm- up After
warm- up When
start- ing When
idling When
racing While
driv- ing
Revision: March 2010 2008 QX56

DRIVE BELTSEM-13
< ON-VEHICLE MAINTENANCE >
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ON-VEHICLE MAINTENANCE
DRIVE BELTS
Checking Drive BeltsINFOID:0000000001538805
WARNING:
Be sure to perform when the engine is stopped.
1. Remove air duct and resonator assembly when inspecting drive belt.
2. Make sure that indicator (single line notch) of eac
h auto tensioner is within the allowable working range
“A” (between three line notches) as shown.
NOTE:
• Check the drive belt auto tensioner indication when the engine is cold.
• The indicator notch is located on the moving side of the drive belt auto tensioner.
3. Visually check entire belt for wear, damage or cracks.
4. If the indicator is out of allowable working range or belt is damaged, replace the belt. Refer to EM-13
.
DRIVE BELT TENSION
There is no manual drive belt tension adjustment. The driv e belt tension is automatically adjusted by the drive
belt auto tensioner.
Removal and InstallationINFOID:0000000001538806
REMOVAL
1. Remove the air duct and resonator assembly. Refer to EM-25, "Removal and Installation".
1. Drive belt2. Power steering pump pulley 3. Generator pulley
4. Crankshaft pulley 5. A/C compressor6. Idler pulley
7. Cooling fan pulley 8. Water pump pulley9. Drive belt auto tensioner
LBIA0391E
Revision: March 2010 2008 QX56

EM-16
< ON-VEHICLE MAINTENANCE >
SPARK PLUG
SPARK PLUG
Removal and InstallationINFOID:0000000001538809
REMOVAL
1. Remove engine room cover using power tool. Refer to EM-24, "Removal and Installation".
2. Remove ignition coil. Refer to EM-37, "
Removal and Installation".
3. Remove spark plug using suitable tool.
INSPECTION AFTER REMOVAL
• Do not use a wire brush for cleaning.
• If plug tip is covered with carbon, spark plug cleaner may be used.
1. Ignition coil 2. Spark plug
WBIA0796E
SEM294A
Cleaner air pressure:
Less than 588 kPa (5.9 bar, 6 kg/cm
2 , 85 psi)
Cleaning time: Less than 20 seconds
SMA773C
Revision: March 2010 2008 QX56

EM-18
< ON-VEHICLE MAINTENANCE >
CAMSHAFT VALVE CLEARANCE
CAMSHAFT VALVE CLEARANCE
Valve ClearanceINFOID:0000000001538810
INSPECTION
NOTE:
Perform the following inspection after removal, installation or replacement of camshaft or valve-related parts,
or if there are unusual engine conditions due to changes in valve clearance over time (starting, idling, and/or
noise).
1. Warm up the engine. Then stop the engine.
2. Remove the engine room cover. Refer to EM-24, "
Removal and Installation".
3. Remove the air cleaner and air duct assembly. Refer to EM-25, "
Removal and Installation".
4. Remove the RH bank and LH bank rocker covers using power tool. Refer to EM-38, "
Removal and Instal-
lation".
5. Turn the crankshaft pulley in the normal direction (clockwise when viewed from engine front) to align TDC identification notch
(without paint mark) with timing indicator.
6. At this time, make sure both the intake and exhaust cam noses of No. 1 cylinder (top front on LH bank) face outside.
• If they do not face outside, turn crankshaft pulley once more.
KBIA2476E
KBIA0400J
Revision: March 2010 2008 QX56

CAMSHAFT VALVE CLEARANCEEM-19
< ON-VEHICLE MAINTENANCE >
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7. Measure valve clearances at the locations marked “×
” as shown
in the table below (locations indicated with black arrow).
• : Engine front
• (black): Measurable at No.1 cylinder compression top dead center
• (white): Measurable at No. 3 cylinder compression top dead center
•A: RH
•B: LH
• C: Exhaust
• D: Intake
NOTE:
Firing order 1-8-7-3-6-5-4-2
• No. 1 cylinder compression TDC
• Measure valve clearance using suitable tool. Refer to EM-108,
"Standard and Limit".
CAUTION:
If the inspection was carried out with a cold engine, make
sure the values with a fully warmed up engine are still
within specifications.
8. Turn the crankshaft pulley clockwise 270 ° from the position of No. 1 cylinder compression TDC to obtain
No. 3 cylinder compression TDC.
Measuring position (RH bank) No. 2 cyl
(E) No. 4 cyl
(F) No. 6 cyl
(G) No. 8 cyl
(H)
No. 1 cylinder at TDC EXH
×
INT ××
Measuring position (LH bank) No. 1 cyl
(J) No. 3 cyl
(K) No. 5 cyl
(L) No. 7 cyl
(M)
No. 1 cylinder at TDC INT
××
EXH ××
WBIA0713E
KBIA0185E
Revision: March 2010 2008 QX56

EM-20
< ON-VEHICLE MAINTENANCE >
CAMSHAFT VALVE CLEARANCE
9. Measure valve clearances at the locations marked “×” as shown
in the table below (locations indicated with white arrow).
• : Engine front
• (black): Measurable at No.1 cylinder compression top dead center
• (white): Measurable at No. 3 cylinder compression top dead center
•A: RH
•B: LH
• C: Exhaust
•D: Intake
NOTE:
Firing order 1-8-7-3-6-5-4-2
• No. 3 cylinder compression TDC
• Measure valve clearance using suitable tool. Refer to EM-108,
"Standard and Limit".
CAUTION:
If the inspection was carried out with a cold engine, make
sure the values with a fully warmed up engine are still
within specifications.
Measuring position (RH bank) No. 2 cyl
(E) No. 4 cyl
(F) No. 6 cyl
(G) No. 8 cyl
(H)
No. 3 cylinder at TDC EXH
×
INT ×
Measuring position (LH bank) No. 1 cyl
(J) No. 3 cyl
(K) No. 5 cyl
(L) No. 7 cyl
(M)
No. 3 cylinder at TDC INT
××
EXH ××
WBIA0713E
KBIA0185E
Revision: March 2010 2008 QX56

CAMSHAFT VALVE CLEARANCEEM-21
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10. Turn the crankshaft pulley clockwise 90°
from the position of No.
3 cylinder compression TDC (clockwise by 360 ° from the posi-
tion of No. 1 cylinder compression TDC) to measure the intake
and exhaust valve clearances of No. 6 cylinder and the exhaust
valve clearance of No. 2 cylinder.
• : Front
•A: RH
•B: LH
• C: Exhaust
• D: Intake
• E: No. 2 cylinder
• F: No. 4 cylinder
• G: No. 6 cylinder
• H: No. 8 cylinder
• J: No. 1 cylinder
• K: No. 3 cylinder
• L: No. 5 cylinder
• M: No. 7 cylinder
11. If out of specifications, adjust as necessary.
ADJUSTMENT
NOTE:
• Perform adjustment depending on the selected head thickness of the valve lifter.
• The specified valve lifter thickness is the dimension at normal temperatures. Ignore dimensional differences
caused by temperature. Us e the specifications for hot engine condition to adjust.
1. Remove the camshaft. Refer to EM-53, "
Removal and Installation".
2. Remove the valve lifters at the locations that are out of specification.
3. Measure the center thickness of the removed valve lifters using suitable tool.
4. Use the equation below to calculate the valve lifter thickness for replacement.
• Valve lifter thickness calculation:Thickness of replacement valve lifter = t1+ (C1 - C2)
t1 = Thickness of removed valve lifter
C1 = Measured valve clearance
C2= Standard valve clearance:
• Thickness of a new valve lifter can be identified by stamp marks on the reverse side (inside the cylinder).
Stamp mark N788 indicates 7.88 mm (0.3102 in) in thickness.
• Available thickness of valve lifter: 25 sizes with range 7.88 to 8.36 mm (0.3102 to 0.3291 in) in steps of 0.02 mm (0.0008 in)
(when manufactured at factory). Refer to EM-108, "
Standard
and Limit".
5. Install the selected valve lifter.
WBIA0713E
KBIA0057E
KBIA0119E
Revision: March 2010 2008 QX56