INFINITI QX56 2011 Factory Service Manual

PREPARATIONEM-9
< PREPARATION >
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Commercial Service ToolINFOID:0000000006289519
KV101197S0
(—)
Injector seal drift set
Installing fuel injector seal ring
EG15050500
(J-45402)
Compression gauge adapter Checking compresion pressure
Tool number
(Kent-Moore No.)
Tool name
Description
JPBIA3281ZZ
ZZA1225D
(Kent-Moore No.)
Tool name
Description
(—)
Tube presser Pressing the tube of liquid gasket
(—)
Power tool Loosening nuts and bolts
(—)
Spark plug wrench Removing and installing spark plug
a: 14 mm (0.55 in)
(—)
Manual lift table caddy Removing and installing engine
S-NT052
PBIC0190E
JPBIA0399ZZ
ZZA1210D
Revision: 2010 May2011 QX56

EM-10
< PREPARATION >
PREPARATION
(—)
Pilot bushing pullerRemoving pilot converter
(—)
Valve seat cutter set Finishing valve seat (EXH) dimensions
(—)
Piston ring expander Removing and installing piston ring
(—)
Valve guide drift Removing and installing valve guide (EXH)
a: 9.5 mm (0.374 in) dia.
b: 5.5 mm (0.217 in) dia.
(—)
Valve guide reamer (A): Reaming valve guide (EXH) inner hole
(B): Reaming hole for oversize valve guide
(EXH)
c: 6.0 mm (0.236 in) dia.
d: 10.2 mm (0.402 in) dia.
(J-43897-18)
(J-43897-12)
Oxygen sensor thread cleaner Reconditioning the exhaust system threads be-
fore installing a new heated oxygen sensor (Use
with anti-seize lubricant shown below.)
a: J-43897-18 (18 mm dia.) for zirconia heat-
ed oxygen sensor and air fuel ratio sensor

b: J-43897-12 (12 mm dia.) for titania heated
oxygen sensor and air fuel ratio sensor
(—)
Anti-seize lubricant (Permatex 133AR
or equivalent meeting MIL specifica-
tion MIL-A-907) Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads
(Kent-Moore No.)
Tool name
Description
NT045
S-NT048
S-NT030
JPBIA0400ZZ
JPBIA0401ZZ
AEM488
AEM489
Revision: 2010 May2011 QX56

PREPARATIONEM-11
< PREPARATION >
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Feeler gauge
Inspection valve clearance (use a curved-tip
gauge)
(—)
Compression gauge with flexible type
adapter Checking compression pressure
(Kent-Moore No.)
Tool name
Description
JPBIA1362ZZ
Revision: 2010 May2011 QX56

EM-12
< BASIC INSPECTION >
CAMSHAFT VALVE CLEARANCE
BASIC INSPECTION
CAMSHAFT VALVE CLEARANCE
InspectionINFOID:0000000006289520
INSPECTION
Check valve clearance if applicable to the following cases:
Intake side:
 At the removal and installation of VVEL ladder assembly or valve-related parts, or at the occurrence of mal-
function (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.
CAUTION:
Valve clearance check on the intake side is not required after replacing the VVEL ladder assembly &
cylinder head assembly with a new one. (Install new VVEL ladder assembly & cylinder head assembly
in factory-shipped condition because it is factory-adjusted and inspected.)
NOTE:
VVEL ladder assembly cannot be replaced as a singl e part, because it is machined together with cylinder
head assembly.
Exhaust side: At the removal, installation, and replacement of exhaus t camshaft or valve-related parts, or at the occur-
rence of malfunction (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clear-
ance.
1. Remove VVEL actuator motor assembly. Refer to EM-36, "
Removal and Installation".
2. Remove rocker covers (bank 1 and bank 2). Refer to EM-33, "
Removal and Installation".
3. Remove VVEL actuator housing assembly. Refer to EM-36, "
Removal and Installation".
4. Measure the valve clearance as per the following:  Use the feeler gauge (commercial service tool) of cu rved-tip. This allows the feeler gauge to access the
clearance between camshaft (drive shaft) nose and valve lifter with ease.
NOTE:
Be sure to note the following points when measuring valve clearance on the intake side.
 Before measuring, check that the position of drive shaft nose
is within the angle shown in the figure.
 Refer to the figure for the insertion direction of the feeler gauge since the direction depends on the bank.Valve clearance : Refer to
EM-133, "
Camshaft".
A: Bank 2
B : Feeler gauge (commercial service tool)
c : 45 degrees (drive shaft nose angle)
D: View D
: Insertion direction of feeler gauge on the bank 2
: Insertion direction of feeler gauge on the bank 1
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Revision: 2010 May2011 QX56

CAMSHAFT VALVE CLEARANCEEM-13
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a. Set No. 1 cylinder at TDC of its compression stroke.
 Rotate crankshaft pulley clockwise to align timing mark
(grooved line without color) (B) with timing indicator (A).
 Check that exhaust cam nose on No. 1 cylinder (engine front side of bank 1) is located as shown in the figure.
 If not, turn crankshaft one revolution (360 degrees) and align as shown in the figure.
 By referring to the figure, measure the valve clearances at locations marked “ ×” as shown in the table below (locations
indicated in the figure).
 No. 1 cylinder at compression TDC
NOTE:
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1 : Exhaust camshaft (bank 1) : Engine front
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: Engine front
Measuring position [bank 2 (A)] No. 2
CYL. No. 4
CYL. No. 6
CYL. No. 8
CYL.
No. 1 cylinder at com- pression TDC EXH
× (C)
INT × (D) × (E)
Measuring position [bank 1 (B)] No. 1
CYL. No. 3
CYL. No. 5
CYL. No. 7
CYL.
No. 1 cylinder at com- pression TDC INT
× (F) × (G)
EXH × (H) × (I)
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Revision: 2010 May2011 QX56

EM-14
< BASIC INSPECTION >
CAMSHAFT VALVE CLEARANCE
To measure valve clearance of No. 1 cylinder INT valve (front
side), insert feeler gauge (A) (commercial service tool) as shown
in the figure.
b. Rotate crankshaft 270 degrees clockwise (when viewed from engine front) to align No. 3 cylinder at TDC its compression stroke.
NOTE:
Crankshaft pulley mounting bolt flange has an angle mark (B)
every 90 degrees (c). They can be used as a guide to rotation
angle.
 By referring to the figure, measure the valve clearances atlocations marked “ ×” as shown in the table below (locations
indicated in the figure).
 No. 3 cylinder at compression TDC
c. Rotate crankshaft 90 degrees clockwise (when viewed from engine front) to align No. 6 cylinder at TDC of compression stroke.
NOTE:
: Engine front
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A : Paint mark
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: Engine front
Measuring position [bank 2 (A)] No. 2
CYL. No. 4
CYL. No. 6
CYL. No. 8
CYL.
No. 3 cylinder at com- pression TDC EXH
× (C)
INT × (D)
Measuring position [bank 1 (B)] No. 1
CYL. No. 3
CYL. No. 5
CYL. No. 7
CYL.
No. 3 cylinder at com- pression TDC INT
× (E) × (F)
EXH × (G) × (H)
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Revision: 2010 May2011 QX56

CAMSHAFT VALVE CLEARANCEEM-15
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Crankshaft pulley mounting bolt flange has an angle mark (B)
every 90 degrees (c). They can be used as a guide to rotation
angle.
 By referring to the figure, measure the valve clearances at
locations marked “ ×” as shown in the table below (locations
indicated in the figure).
 No. 6 cylinder at compression TDC
5. Perform adjustment or repl acement if the measured value is out of the standard.
 If a valve clearance on the exhaust side is out of s pecification, adjust the valve clearance. Refer to EM-
77, "Inspection".
 If a valve clearance on the intake side is out of s pecification, replace VVEL ladder assembly & cylinder
head assembly. Refer to EM-86, "
Exploded View".
CAUTION:
Never adjust valve clearance on the intake side.
NOTE:
Since the valve lifter (INT) cannot be replaced by the piece, VVEL ladder assembly & cylinder head
assembly replacement are required.
A : Paint mark
JPBIA2066ZZ
: Engine front
Measuring position [bank 2 (A)] No. 2
CYL. No. 4
CYL. No. 6
CYL. No. 8
CYL.
No. 6 cylinder at com- pression TDC EXH
× (B) × (C)
INT × (D)
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Revision: 2010 May2011 QX56

EM-16
< BASIC INSPECTION >
COMPRESSION PRESSURE
COMPRESSION PRESSURE
InspectionINFOID:0000000006289521
1. Warm up engine thoroughly. Then, stop it.
2. Release fuel pressure. Refer to EC-153, "
Work Procedure".
CAUTION:
If CONSULT-III is not used to release fuel pr essure leave the fuel pump fuse disconnected until
step 7.
3. Remove fuel pump fuse in IPDM E/R. NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
4. Remove engine cover. Refer to EM-25, "
Exploded View".
5. Remove ignition coil and spark plug from each cylinder. Refer to EM-29, "
Exploded View".
6. Connect engine tachometer (not required in use of CONSULT-III).
7. Install the compression tester with Tool [SST: EG15050500 (J- 45402)] into the spark plug hole.
8. Measure compression pressure using compressi on gauge connected with flexible type adapter (commer-
cial service tool).
9. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge pointer stabilizes, read the compression pressure and the engine rpm. Perform these steps to check each
cylinder.
CAUTION:
 Measure a six-cylinder under the same conditio ns since a measurement depends on measure-
ment conditions (engine water temperature, etc.).
 Always use a fully changed battery to obtain the specified engine speed.
 If the engine speed is out of the specified range, c heck battery liquid for proper gravity. Check the
engine speed again with normal battery gravity. Refer to PG-159, "
How to Handle Battery".
 If compression pressure is below the minimum value, check valve clearances and parts associated with combustion chamber (valve, valve seat, piston, pi ston ring, cylinder bore, cylinder head, cylinder head
gasket). After checking, measure compression pressure again.
 If a cylinder has low compression pressure, pour a small amount of engine oil into the spark plug hole of the cylinder to re-check it for compression.
- If the added engine oil improves the compression, pi ston rings may be worn out or damaged. Check pis-
ton rings and replace if necessary. Refer to EM-107, "
Disassembly and Assembly".
- If the compression pressure remains at low level despite the addition of engine oil, valves may be mal- functioning. Check valves for damage. Replace valve or valve seat accordingly. Refer to EM-107, "
Dis-
assembly and Assembly".
 If two adjacent cylinders have respectively low co mpression pressure and their compression remains
low even after the addition of engine oil, cylinder head gaskets are leaking. In such a case, replace cyl-
inder head gaskets. Refer to EM-87, "
Removal and Installation".
10. After inspection is completed, install removed parts.
11. Start the engine, and check that the engine runs smoothly.
WBIA0605E
Compression pressure : Refer to EM-132, "GeneralSpecification".
Revision: 2010 May2011 QX56

COMPRESSION PRESSUREEM-17
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12. Perform trouble diagnosis. If DTC appears, erase it. Refer to
EC-161, "Description".
Revision: 2010 May2011 QX56

EM-18
< SYMPTOM DIAGNOSIS >
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting - Engine NoiseINFOID:0000000006289522
JPBIA3483GB
Revision: 2010 May2011 QX56