INFINITI QX56 2011 Factory Service Manual

CYLINDER HEADEM-89
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
Disassembly and AssemblyINFOID:0000000006365632
DISASSEMBLY
1. Remove valve collet.
 Compress valve spring with the valve spring compressor [SST:
KV10116200 (J-26336-A)] (A), the attachment [SST:
KV10115900 (J-26336-20)] (C) and the adapter [SST:
KV10109220 ( — )] (B). Remove valve collet with a magnet
hand.
CAUTION:
When working, take care not to damage valve lifter holes.
2. Remove valve spring retainer and valve spring (with valve spring seat).
3. Push valve stem to combustion chamber side, and remove valve.  Identify installation positions, and store them without mixing them up.
4. Remove valve oil seal using the valve oil seal puller [SST: KV10107902 (J38959)] (A).
5. Remove valve seat (EXH), if valve seat (EXH) must be replaced.  Bore out old seat until it collapses. Boring s hould not continue beyond the bottom face of the seat
recess in cylinder head. Set the machi ne depth stop to ensure this. Refer to EM-135, "
CylinderHead".
CAUTION:
Prevent to scratch cylinder head by excessive boring.
6. Remove valve guide (EXH), if valve guide (EXH) must be replaced.
a. To remove valve guide (EXH), heat cylinder head to 110 to 130°C (230 to 266 °F) by soaking in heated oil (A).
JPBIA1365ZZ
JPBIA1366ZZ
JPBIA0184ZZ
Revision: 2010 May2011 QX56

EM-90
< REMOVAL AND INSTALLATION >
CYLINDER HEAD
b. Drive out valve guide (EXH) with a press [under a 20 kN (2 ton,2.2 US ton, 2.0 lmp ton) pressure] or a hammer and the valve
guide drift (commercial service tool).
WARNING:
Cylinder head contains heat . When working, wear protec-
tive equipment to avo id getting burned.
ASSEMBLY
1. Install valve guide (EXH), if removed.
Replace with oversized [0.2 mm (0.008 in)] valve guide (EXH).
a. Using the valve guide reamer (commercial service tool) (A), ream cylinder head valve guide (EXH) hole.
b. Heat cylinder head to 110 to 130 °C (230 to 266 °F) by soaking in
heated oil (A).
c. Using the valve guide drift (commercial service tool), press valve guide (EXH) from camshaft side to the dimensions as shown in
the figure.
WARNING:
Cylinder head contains heat . When working, wear protec-
tive equipment to avo id getting burned.
SEM931C
Oversize (service) [0.2 mm (0.008 in)]:
: Refer to EM-135, "
CylinderHead".
JPBIA0185ZZ
JPBIA0184ZZ
Projection (A)
: Refer to EM-135, "
CylinderHead".
JPBIA0186ZZ
Revision: 2010 May2011 QX56

CYLINDER HEADEM-91
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
d. Using the valve guide reamer (commercial service tool) (A),
apply reamer finish to valve guide (EXH).
2. Install valve seat (EXH), if removed. Replace with oversize [0.5 mm (0.020 in)] valve seat (EXH).
a. Ream cylinder head recess diameter (a) for service valve seat (EXH).
 Be sure to ream in circles concentric to valve guide center.
This enables valve to fit correctly.
b. Heat cylinder head to 110 to 130 °C (230 to 266 °F) by soaking in
heated oil (A).
c. Provide valve seats (EXH) cooled well with dry ice. Force fit valve seat (EXH) into cylinder head. WARNING:
Cylinder head contains heat. When working, w ear protective equipment to avoid getting burned.
CAUTION:
Avoid directly touching cold valve seats.
d. Using the valve seat cutter set (commercial service tool) or valve seat grinder, finish seat to the specified dimensions. Refer to
EM-135, "
CylinderHead".
CAUTION:
When using the valve seat cutt er, firmly grip cutter handle
with both hands. Then, press on the contacting surface all
around the circumference to cu t in a single drive. Improper
pressure on cutter or cutting many different times may
result in staged valve seat.
e. Using compound, grind to adjust valve fitting.
f. Check again for normal contact. Refer to EM-92, "
Inspection".
3. Install new valve oil seals as per the following: Standard : Refer to
EM-135, "
CylinderHead".
JPBIA0185ZZ
Oversize (service) [0.5 mm (0.020 in)]:
: Refer to EM-135, "
CylinderHead".
JPBIA0188ZZ
JPBIA0184ZZ
SEM934C
Revision: 2010 May2011 QX56

EM-92
< REMOVAL AND INSTALLATION >
CYLINDER HEAD
a. Apply new engine oil on new valve oil seal joint and seal lip.
b. Using the valve oil seal drift [SST: KV10115600 (J-38958)] (A),press fit valve seal to height (b) shown in figure.
4. Install valve. NOTE:
Larger diameter valves are for intake side.
5. Install valve spring (with valve spring seat).  Install narrow pitch (B) end [paint mark (C)] to cylinder headside (valve spring seat side).
6. Install valve spring retainer.
7. Install valve collet.  Compress valve spring with the valve spring compressor [SST:
KV10116200 (J26336-A)] (A), the attachment [SST:
KV10115900 (J26336-20)] (C) and the adapter [SST:
KV10109220 ( — )] (B). Install valve collet with a magnet
hand.
CAUTION:
When working, take care not to damage valve lifter holes.
 Tap valve stem edge lightly with plastic hammer after installa- tion to check its installed condition.
InspectionINFOID:0000000006289573
INSPECTION AFTER DISASSEMBLY
Cylinder Head Bolt s Outer Diameter
 Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between (B) and (A)
exceeds the limit, replace them with new one.
 If reduction of outer diameter appears in a position other than (A),
use it as (A) point. Height (b)
Intake, Exhaust : 14.3 - 14.9 mm (0.563 - 0.587 in)
JPBIA1367ZZ
A : Wide pitch
: Cylinder head side
Paint mark color
Intake : Light green
Exhaust : Light blue
JPBIA0179ZZ
JPBIA1365ZZ
Limit [(B) - (A)] : 0.18 mm (0.0071 in)
c : 55 mm (2.17 in)
d : 12 mm (0.47 in)
JPBIA2144ZZ
Revision: 2010 May2011 QX56

CYLINDER HEADEM-93
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
Cylinder Head Distortion
NOTE:
When performing this inspection, cylinder block distortion should be also checked. Refer to
EM-115, "
Inspec-
tion".
1. Using a scraper, wipe out oil, scale, gasket, s ealant and carbon deposits from surface of cylinder head.
CAUTION:
Never allow gasket fragments to enter engine oil or engine coolant passages.
2. At each of several locations on bottom surface of cylinder head, measure the distortion in six directi ons (A), (B), (C), (D), (E), and
(F).
 If it exceeds the limit, replace VVEL ladder assembly & cylinder head assembly.
NOTE:
Cylinder head assembly cannot be replaced as a single part,
because it is machined together with VVEL ladder assembly.
Valve Dimensions
 Check the dimensions of each valv e. For the dimensions, refer to EM-135, "CylinderHead".
 If dimensions are out of the standard.
- Replace valve (EXH) and check valve seat contact. Refer to "VALVE SEAT CONTACT". (Exhaust side)
- Replace VVEL ladder assembly & cylinder head assembly. Refer to EM-86, "
Exploded View". (Intake side)
NOTE:
Since the valve (INT) cannot be replaced by the pi ece, VVEL ladder assembly & cylinder head assembly
replacement are required.
Valve Guide Clearance
Valve Stem Diameter
 Measure the diameter of valve stem with micrometer (A).
Valve Guide Inner Diameter
 Measure the inner diameter of valve guide with bore gauge.
Valve Guide Clearance
 (Valve guide clearance) = (Valve guide inner diameter) – (Valve
stem diameter)
 If the calculated value exceeds the limit.
- Replace valve (EXH) and/or valve guide (EXH). Refer to EM-86, "
Exploded View". (Exhaust side)
- Replace VVEL ladder assembly & cylinder head assembly. Refer to EM-86, "
Exploded View". (Intake side)
NOTE:
Since the valve (INT) and valve guide (INT) cannot be repl aced by the piece, VVEL ladder assembly & cylin-
der head assembly replacement are required.
Valve Seat Contact
 After confirming that the dimensions of valve guides and valves are within the specifications, perform this
procedure.
 Apply prussian blue (or white lead) onto contacting surfac e of valve seat to check the condition of the valve
contact on the surface. Limit : Refer to
EM-135, "
CylinderHead".
JPBIA0176ZZ
Standard : Refer to EM-135, "CylinderHead".
Standard : Refer to EM-135, "
CylinderHead".
Standard : Refer to EM-135, "
CylinderHead".
JPBIA0183ZZ
Revision: 2010 May2011 QX56

EM-94
< REMOVAL AND INSTALLATION >
CYLINDER HEAD
 Check if the contact area band is continuous all around the circum-ference.
- If not, grind to adjust valve fitting and check again. If the contacting surface still has “NG” conditions even after the re-check, replace
valve seat (EXH). Refer to EM-86, "
Exploded View". (Exhaust
side)
- If not, replace VVEL ladder assembly & cylinder head assembly. Refer to EM-86, "
Exploded View". (Intake side)
NOTE:
Since the valve seat (INT) cannot be replaced by t he piece, VVEL ladder assembly & cylinder head assem-
bly replacement are required.
Valve Spring (with valve spring seat) Squareness
 Set a try square (A) along the side of valve spring (with valve
spring seat) and rotate spring. Measure the maximum clearance
between the top of spring and try square.
 If it exceeds the limit.
- Replace valve spring (with valve spring seat) (EXH). Refer to EM-
86, "Exploded View". (Exhaust side)
- Replace VVEL ladder assembly & cylinder head assembly. Refer
to EM-86, "
Exploded View". (Intake side)
NOTE:
Since the valve spring (with valve spring seat) (INT) c annot be replaced by the piece, VVEL ladder assembly
& cylinder head assembly replacement are required.
Valve Spring Dimensions and Valve Spring Pressure Load
 Check the valve spring (with valve spring seat) pressure at speci- fied spring height.
 If the installation load or load with valve open is out of the stan- dard.
- Replace valve spring (with valve spring seat) (EXH). Refer to EM-
86, "Exploded View". (Exhaust side)
- Replace VVEL ladder assembly & cylinder head assembly. Refer to EM-86, "
Exploded View". (Intake side)
NOTE:
Since the valve spring (with valve spring seat) (INT) c annot be replaced by the piece, VVEL ladder assembly
& cylinder head assembly replacement are required.
INSPECTION AFTER ASSEMBLY
Inspection for Leakage
The following are procedures for checking fluid leakage, lubricant leakage.
 Before starting engine, check oil/fluid levels includi ng engine coolant and engine oil. If any are less than the
required quantity, fill them to the specified level. Refer to MA-10, "
Fluids and Lubricants".
 Follow the procedure below to check for fuel leakage.
- Turn ignition switch to the “ON” position (with engi ne stopped). With fuel pressure applied to fuel piping,
check for fuel leakage at connection points.
- Start engine. With engine speed increased, che ck again for fuel leakage at connection points.
 Run engine to check for unusual noise and vibration. NOTE:
A: OK
B: NG
JPBIA0187ZZ
B : Contact
Limit : Refer to EM-135, "CylinderHead".
JPBIA0189ZZ
Standard
: Refer to EM-135, "
CylinderHead".
SEM113
Revision: 2010 May2011 QX56

CYLINDER HEADEM-95
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
If hydraulic pressure inside chain tensioner drops after removal/installation, slack in guide may generate a
pounding noise during and just after the engine start. However, this does not indicate a malfunction. The
noise will stop after hydraulic pressure rises.
 Warm up engine thoroughly to check that there is no leak age of fuel, or any oil/fluids including engine oil and
engine coolant.
 Bleed air from lines and hoses of applicable lines, such as in cooling system.
 After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill them to
the specified level, if necessary.
Summary of the inspection items:
* Power steering fluid, brake fluid, etc. Items Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Transmission /
transaxle fluid AT & CVT Models Leakage Level / Leakage Leakage
MT Models Level / Leakage Leakage Level / Leakage
Other oils and fluids* Level Leakage Level
Fuel Leakage Leakage Leakage
Revision: 2010 May2011 QX56

EM-96
< REMOVAL AND INSTALLATION >
OIL SEAL
OIL SEAL
FRONT OIL SEAL
FRONT OIL SEAL : Removal and InstallationINFOID:0000000006289574
REMOVAL
1. Remove the following parts:
 Front under cover, using a power tool. Refer to EXT-25, "
Exploded View".
 Drive belt: Refer to EM-20, "
Exploded View".
 Cooling fan: Refer to CO-16, "
Exploded View".
2. Remove crankshaft pulley as per the following:
a. Remove rear plate cover. Refer to EM-54, "
Exploded View".
b. Set the ring gear stopper [SST: KV10120100 (J-47245)] (A) as shown in the figure.
c. Loosen crankshaft pulley bolt, and then pull crankshaft pulley with both hands to remove it.
CAUTION:
Never remove crankshaft pulley bolt. Keep loosened crank-
shaft pulley bolt in place to protect removed crankshaft pul-
ley from dropping.
3. Remove front oil seal using a suitable tool. CAUTION:
Be careful not to damage front cover and crankshaft.
INSTALLATION
1. Install front oil seal on front cover.
 Apply new engine oil to both oil seal lip (A) and dust seal lip(B).
 Install it so that each seal lip is oriented as shown in the figure. CAUTION:
Be careful not to scratch or make burrs on circumference
of oil seal.
 Using a suitable drift [outer diameter: 56 mm (2.20 in)], press- fit oil seal until it becomes flush with front cover end face.
 Check the garter spring is in position and seal lips are not inverted.
2. Install in the reverse order of removal.
REAR OIL SEAL
LBIA0455E
JPBIA3472ZZ
: Engine inside
: Engine outside
JPBIA0054ZZ
Revision: 2010 May2011 QX56

OIL SEALEM-97
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
REAR OIL SEAL : Removal and InstallationINFOID:0000000006289575
REMOVAL
1. Remove transmission assembly. Refer to
TM-205, "2WD : Exploded View" (2WD models) or TM-208,
"4WD : Exploded View" (4WD models).
2. Remove drive plate. Refer to EM-106, "
Exploded View".
3. Remove rear oil seal with a suitable tool. CAUTION:
Be careful not to damage crankshaft and cylinder block.
INSTALLATION
1. Install rear oil seal. Install rear oil seal so that each seal lip is oriented as shown in
the figure.
 Press in rear oil seal (1) to the position as shown in the figure.
 Using a suitable drift [outer diameter 101 mm (3.98 in)], press-fit until the height of rear oil seal is level with the mounting surface.
 Check the garter spring is in position and seal lips are not inverted. CAUTION:
 Be careful not to damage crankshaft and cylinder block.
 Press-fit straight and avoid cau sing burrs or tilting oil seal.
2. Install in the reverse order of removal after this step.
SBIA0360E
A : Oil seal lip
B : Dust seal lip : Engine inside
: Engine outside
JPBIA0054ZZ
B : Rear oil seal retainer rear end face
a : 0 - 0.5 mm (0 - 0.020 in)
JPBIA0152ZZ
SBIA0360E
Revision: 2010 May2011 QX56

EM-98
< UNIT REMOVAL AND INSTALLATION >
ENGINE ASSEMBLY
UNIT REMOVAL AND INSTALLATION
ENGINE ASSEMBLY
Exploded ViewINFOID:0000000006289576
2WD models
JPBIA4257GB
1. Heat shield plate (RH) 2. Engine mounting insulator (RH) 3. Engine mounting bracket (RH)
4. Engine mounting bracket (LH) 5. Engine mounting insulator (LH) 6. Heat shield plate (LH)
7. Rear engine mounting cross member 8. Rear engine mounting insulator
Refer to GI-4, "
Components" for symbols in the figure.
Revision: 2010 May2011 QX56