engine INFINITI QX56 2004 Factory Service Manual

EM-54Revision: August 2007
CAMSHAFT
2004 QX56
CAUTION:
If inspection was carried out with cold engine, make sure values with fully warmed up engine
are still within specifications.
7. Turn crankshaft pulley clockwise by 270° from the position of No. 1 cylinder compression TDC to obtain
No. 3 cylinder compression TDC.
8. Measure valve clearances at locations marked “×” as shown in
the table below (locations indicated with white arrow).

No. 3 cylinder compression TDC
9. Turn crankshaft pulley clockwise by 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 intake and
exhaust valve clearances of No. 6 cylinder and exhaust valve
clearance of No. 2 cylinder.
10. If out of specifications, adjust as necessary. Refer to EM-54, "
ADJUSTMENT" .
ADJUSTMENT
NOTE:

Perform adjustment depending on selected head thickness of valve lifter.

The specified valve lifter thickness is the dimension at normal temperatures. Ignore dimensional differ-
ences caused by temperature. Use the specifications for hot engine condition to adjust.
1. Remove camshaft. Refer to EM-43, "
Removal and Installation" .
2. Remove the valve lifters at the locations that are out of specification.
Measuring position (RH bank) No. 2 CYL No. 4 CYL No. 6 CYL No. 8 CYL
No. 3 cylinder at TDC EXH ×
INT ×
Measuring position (LH bank) No. 1 CYL No. 3 CYL No. 5 CYL No. 7 CYL
No. 3 cylinder at TDCINT××
EXH××
KBIA2526E
KBIA2548E

CAMSHAFT
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3. Measure the center thickness of the removed valve lifters using
suitable tool.
4. Use the equation below to calculate 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-101, "
Available
Valve Lifter" .
5. Install the selected valve lifter.
6. Install camshaft.
7. Manually turn crankshaft pulley a few turns.
8. Make sure valve clearances for cold engine are within specifications by referring to the specified values.
9. After completing the repair, check valve clearances again with the specifications for warmed engine. Make
sure the values are within specifications.
KBIA0057E
Intake : 0.36 mm (0.0142 in)*
Exhaust : 0.37 mm (0.0146 in)*
*: Approximately 80°C (176°F)
KBIA0 119 E
Valve clearance standard:
Hot*
Intake : 0.304 - 0.416 mm (0.012 - 0.016 in)
Exhaust : 0.308 - 0.432 mm (0.012 - 0.017 in)
Cold
Intake : 0.26 - 0.34 mm (0.010 - 0.013 in)
Exhaust : 0.29 - 0.37 mm (0.011 - 0.015 in)
* : Approximately 80°C (176°F)

EM-56Revision: August 2007
OIL SEAL
2004 QX56
OIL SEALPFP:00100
Removal and Installation of Valve Oil SealEBS00ILP
REMOVAL
1. Remove camshaft relating to valve oil seal to be removed. Refer to EM-43, "REMOVAL" .
2. Remove valve lifters. Refer to EM-43, "
REMOVAL" .

Correctly identify location where each part is removed. Keep parts organized to avoid mixing them up.
3. Turn crankshaft until the cylinder requiring new oil seals is at TDC. This will prevent the valve from drop-
ping into the cylinder.
4. Remove valve collet using Tool.
CAUTION:
When working, take care not to damage valve lifter holes.
5. Remove valve spring retainer and valve spring.
CAUTION:
Do not remove valve spring seat from valve spring.
6. Remove valve oil seal using Tool.
INSTALLATION
Installation is in the reverse order of removal.

Install valve oil seal using Tool.

Apply new engine oil on new valve oil seal joint and seal lip.

Install valve oil seal to specified height "H".Tool number : KV10116200 (J-26336-B)
: KV10115900 (J-26336-20)
: KV10109220 ( — )
WBIA0578E
Tool number : KV10107902 (J-38959)
WBIA0478E
Tool number : KV10115600 (J-38958)
Height "H" (Without valve spring seat installed)
Intake and exhaust : 14.3 - 14.9 mm (0.563 - 0.587 in)
WBIA0490E

OIL SEAL
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Removal and Installation of Front Oil SealEBS00ILQ
REMOVAL
1. Remove the engine. Refer to EM-70, "REMOVAL" .
2. Remove crankshaft pulley. Refer to EM-35, "
TIMING CHAIN" .
3. Remove the front oil seal using a suitable tool.
CAUTION:
Be careful not to damage front cover and oil pump drive
spacer.
INSTALLATION
1. Apply new engine oil to both oil seal lip and dust seal lip of new front oil seal.
2. Install front oil seal.

Install front oil seal so that each seal lip is oriented as shown.

Press-fit until the height of front oil seal is level with the
mounting surface using suitable tool.
CAUTION:

Be careful not to damage front timing chain case and
crankshaft.

Press-fit straight and avoid causing burrs or tilting oil
seal.
3. Installation of the remaining components is in the reverse order of removal.
Removal and Installation of Rear Oil SealEBS00ILR
REMOVAL
1. Remove transmission assembly. Refer to AT-255, "REMOVAL" (4x2 models) or AT-258, "REMOVAL"
(4x4 models).
a. Remove drive plate.

Holding crankshaft pulley bolts, lock crankshaft to remove drive plate bolts.

Remove the bolts diagonally.
CAUTION:

Be careful not to damage drive plate. Especially avoid deforming and damaging of signal
plate teeth (circumference position).

Place the drive plate with signal plate surface facing other than downward.

Keep magnetic materials away from signal plate.
SBIA0359E
SEM 71 5A
PBIC2931E

EM-58Revision: August 2007
OIL SEAL
2004 QX56
b. Remove engine rear plate.
2. Remove the rear oil seal using a suitable tool.
CAUTION:
Be careful not to damage crankshaft and oil seal retainer
surface.
INSTALLATION
1. Apply new engine oil to both oil seal lip and dust seal lip of new rear seal.
2. Install rear oil seal.

Install rear oil seal so that each seal lip is oriented as shown.

Press-fit rear oil seal using suitable tool.
CAUTION:

Be careful not to damage crankshaft and cylinder
block.

Press-fit oil seal straight to avoid causing burrs or tilt-
ing.

Do not touch grease applied onto oil seal lip.

Do not damage or scratch the outer circumference of
the rear oil seal.

Tap until flattened with the front edge of the oil seal retainer.
3. Installation of the remaining components is in the reverse order of removal.
WBIA0437E
SEM 71 5A
PBIC2933E

CYLINDER HEAD
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Revision: August 20072004 QX56
CYLINDER HEADPFP:11041
On-Vehicle ServiceEBS00ILS
CHECKING COMPRESSION PRESSURE
1. Warm up engine thoroughly. Then stop engine.
2. Release fuel pressure. Refer to EC-46, "
FUEL PRESSURE RELEASE" .
a. Remove fuel pump fuse, and start engine.
Refer to PG-78, "
FUSE AND RELAY BOX" or fuel pump fuse location.

Let fuel pump fuse removed until the end of step 7.
b. After engine stalls, crank it two or three times to release all fuel pressure.
3. Remove ignition coil and spark plug from each cylinder.
Refer to EM-27, "
REMOVAL" .
4. Connect engine tachometer (not required in use of CONSULT-II).
5. Install compression tester with Tool into spark plug hole.
6. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge
pointer stabilizes, read the compression pressure and engine rpm. Perform these steps to check each cyl-
inder.
Unit: kPa (kg/cm2 , psi) /rpm
CAUTION:
Always use a fully charged battery to obtain specified engine speed.

If the engine speed is out of specified range, check battery liquid for proper gravity. Check engine
speed again with normal battery gravity.

If compression pressure is below minimum value, check valve clearances and parts associated with
combustion chamber (valve, valve seat, piston, piston ring, cylinder bore, cylinder head, cylinder head
gasket). After the checking, measure compression pressure again.

If some cylinders have low compression pressure, pour 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, the piston rings may be worn out or damaged. Check
the piston rings and replace if necessary.
–If the compression pressure remains at low level despite the addition of engine oil, the valves may be
malfunctioning. Check the valves for damage. Replace the valve or valve seat accordingly.

If two adjacent cylinders have respectively low compression pressure and their compression remains
low even after the addition of engine oil, the gaskets may be leaking, or valve in adjacent cylinders may
be damaged. Inspect and repair as required.
7. After inspection is complete, install removed parts. Installation is in the reverse order of removal.
8. Start engine, and confirm that engine runs smoothly.
9. Perform trouble diagnosis. If DTC appears, erase it. Refer to EC-71, "
TROUBLE DIAGNOSIS" . Tool number : EG15050500 (J-45402)
WBIA0605E
Standard MinimumDeference limit
between cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 300

EM-60Revision: August 2007
CYLINDER HEAD
2004 QX56
Removal and InstallationEBS00ILT
REMOVAL
1. Remove engine assembly from vehicle. Refer to EM-70, "REMOVAL" .
2. Remove the following components and related parts:

Auto tensioner of drive belts and idler pulley. Refer to EM-12, "DRIVE BELTS" .

Thermostat housing and hose. Refer to CO-17, "Removal of Thermostat Housing, Water Outlet and
Heater Pipe" .

Oil pan and oil strainer. Refer to EM-22, "OIL PAN AND OIL STRAINER" .

Fuel tube and fuel injector assembly. Refer to EM-29, "FUEL INJECTOR AND FUEL TUBE" .

Intake manifold. Refer to EM-15, "INTAKE MANIFOLD" .

Ignition coil. Refer to EM-26, "IGNITION COIL" .

Rocker cover. Refer to EM-33, "ROCKER COVER" .
3. Remove crankshaft pulley, front cover, oil pump, and timing chain. Refer to EM-35, "
TIMING CHAIN" .
4. Remove camshaft sprockets and camshafts. Refer to EM-43, "
CAMSHAFT" .
5. Remove cylinder head bolts in reverse order shown.
1. Harness bracket 2. Engine coolant temperature sensor 3. Washer
4. Cylinder head gasket (left bank) 5. Cylinder head (right bank) 6. Cylinder head bolt
7. Cylinder head gasket (right bank) 8. Cylinder head (left bank)
KBIA2528E
PBIC0068E

CYLINDER HEAD
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INSPECTION AFTER REMOVAL
Cylinder Head Bolts Diameter

Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between d1 and d2
exceeds the limit, replace the bolts with new one.

If reduction of diameter appears in a position other than d2, use
it as d2 point.
INSTALLATION
1. Install cylinder head gasket.
2. Install cylinder head. Follow the steps below and tighten the
bolts in the numerical order shown.
CAUTION:

If cylinder head bolts are re-used, check their diameters
before installation. Refer to EM-61, "
Cylinder Head Bolts
Diameter" .
a. Apply engine oil to threads and seating surface of bolts.
b. Measure tightening angle using Tool.
CAUTION:
Measure tightening angle using Tool. Do not measure visu-
ally.
3. Installation of the remaining components is in the reverse order of removal.Limit (d1 - d2) : 0.18 mm (0.0071 in)
KBIA0189E
Step a : 98.1 N·m (10 kg-m, 72 ft-lb)
Step b :Loosen in the reverse order of tightening.
Step c : 44.1 N·m (4.5 kg-m, 33 ft-lb)
PBIC0068E
Tool number : KV10112100 (BT-8653-A)
Step d : 60° clockwise
Step e : 60° clockwise
WBIA0603E

CYLINDER HEAD
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Revision: August 20072004 QX56
7. Remove valve oil seal using Tool.
8. Replace valve seat if necessary. Refer to EM-68, "
VALVE SEAT REPLACEMENT" .
9. Replace valve guide if necessary. Refer to EM-68, "
VALVE SEAT REPLACEMENT" .
10. Remove spark plug tube, as necessary.

Remove spark plug tube out of cylinder head using suitable tool.
CAUTION:

Take care not to damage cylinder head.

Once removed, spark plug tube will be deformed and cannot be reused. Do not remove it unless
absolutely necessary.
ASSEMBLY
1. Install the valve guide if necessary. Refer to EM-66, "VALVE GUIDE REPLACEMENT" .
2. Install the valve seat if necessary. Refer to EM-68, "
VALVE SEAT REPLACEMENT" .
3. Install valve oil seal using Tool.

Apply new engine oil on new valve oil seal joint and seal lip.

Install valve oil seal to specified height "H".
4. Install valves in their original position.
5. Install valve spring seats.
6. Install valve springs.

Install narrow pitch end (Paint mark side) to cylinder head
side.
7. Install valve spring retainers.Tool number : KV10107902 (J-38959)
WBIA0478E
Tool number : KV10115600 (J-38958)
Height "H" (Without valve spring seat installed)
Intake and exhaust : 14.3 - 14.9 mm (0.563 - 0.587 in)
WBIA0490E
SEM 08 5D

EM-70Revision: August 2007
ENGINE ASSEMBLY
2004 QX56
ENGINE ASSEMBLYPFP:10001
Removal and InstallationEBS00ILW
WAR NIN G:

Situate vehicle on a flat and solid surface.

Place chocks at front and back of rear wheels.

For engines not equipped with engine slingers, attach proper slingers and bolts described in
PARTS CATALOG.
CAUTION:

Always be careful to work safely, avoid forceful or uninstructed operations.

Do not start working until exhaust system and engine coolant are cooled sufficiently.

If items or work required are not covered by the engine section, refer to the applicable sections.

Always use the support point specified for lifting.

Use either 2-point lift type or separate type lift. If board-on type is used for unavoidable reasons,
support at the rear axle jacking point with transmission jack or similar tool before starting work, in
preparation for the backward shift of center of gravity.

For supporting points for lifting and jacking point at rear axle, refer to GI-40, "Garage Jack and
Safety Stand" .
REMOVAL
Preparation
1. Drain engine coolant. Refer to MA-12, "DRAINING ENGINE COOLANT" .
2. Partially drain A/T fluid. Refer to AT - 1 3 , "
Changing A/T Fluid" .
3. Release fuel pressure. Refer to EC-46, "
FUEL PRESSURE RELEASE" .
4. Remove the engine hood. Refer to BL-12, "
HOOD" .
1. Rear engine mounting insulator 4x4 2. Rear engine mounting insulator 4x2 3. LH engine mounting bracket
4. LH heat shield plate 5. LH engine mounting insulator 6. RH engine mounting bracket
7. RH heat shield plate 8. RH engine mounting insulator
LBIA0397E