Air INFINITI QX56 2004 Factory Service Manual

EM-28Revision: August 2007
SPARK PLUG (PLATINUM-TIPPED TYPE)
2004 QX56
CAUTION:

Do not drop or shock spark plug.

Do not use a wire brush for cleaning.

If plug tip is covered with carbon, spark plug cleaner may
be used.

Checking and adjusting plug gap is not required between
change intervals.
INSTALLATION
Installation is in the reverse order of removal.Cleaner air pressure:
Less than 588 kPa (5.9 bar, 6 kg/cm
2 , 85 psi)
Cleaning time:
Less than 20 seconds
SM A77 3C
SM A80 6CA

ROCKER COVER
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ROCKER COVERPFP:13264
Removal and InstallationEBS00ILL
REMOVAL
1. Remove the engine room cover using power tool. Refer to EM-11, "REMOVAL" .
2. Remove the air duct and resonator assembly. Refer to EM-14, "
REMOVAL" (for left bank only) .
3. Move the harness on the upper rocker cover and its peripheral aside.
4. Remove the electric throttle control actuator, loosening bolts diagonally (for left bank only).
5. Remove the ignition coil. Refer to EM-26, "
REMOVAL" .
6. Remove the PCV hose from the PCV control valve.
7. Loosen the bolts in reverse order shown using power tool.
CAUTION:
Do not hold the rocker cover by the oil filler neck (right
bank).
1. Rocker cover (left bank) 2. PCV control valve 3. O-ring
4. Rocker cover gasket (left bank) 5. Rocker cover (right bank) 6. PCV control valve
7. O-ring 8. Oil filler cap 9. Rocker cover gasket (right bank)
KBIA2508E
KBIA2509E

EM-34Revision: August 2007
ROCKER COVER
2004 QX56
INSTALLATION
1. Apply liquid gasket to the joint part of the cylinder head and
camshaft bracket following the steps below.
NOTE:
Illustration shows an example of left bank side (zoomed in
shows No.1 camshaft bracket).
a. Refer to illustration “a” to apply liquid gasket to the joint part of
No.1 camshaft bracket and cylinder head.
b. Refer to illustration “b” to apply liquid gasket 90° to illustration
“a”.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Products and Sealants" .
2. Install the rocker cover.

Make sure the new rocker cover gasket is installed in the groove of the rocker cover.

Tighten bolts in two steps separately in the numerical order
shown.
CAUTION:
Do not hold the rocker cover by the oil filler neck (right
bank).
3. Install the PCV hose using the following procedure.

Remove any foreign materials from inside the hose with com-
pressed air.

Insert the hose within 25 - 30 mm (0.98 - 1.18 in) [Target: 25 mm (0.98 in)].
4. Installation of the remaining components is in the reverse order of removal.
KBIA2510E
1st step : 2.0 N·m (0.2 kg-m, 18 in-lb)
2nd step : 8.3 N·m (0.85 kg-m, 73 in-lb)
KBIA2509E

EM-52Revision: August 2007
CAMSHAFT
2004 QX56

Install intake and exhaust side camshaft sprocket by selec-
tively using the groove of dowel pin according to the bank.
(Common part used for both banks.)
b. Lock the hexagonal part of camshaft in the same way as for
removal, and tighten bolts.
c. Check again that the timing mating mark on timing chain and on
each sprocket are aligned.
6. Install chain tensioner with the following procedure:
NOTE:
Left bank is shown.
a. Install chain tensioner.

Compress plunger and hold it with a stopper pin when install-
ing.

Loosen the slack guide side timing chain by rotating camshaft
hexagonal part if mounting space is small.
b. Remove stopper pin and release plunger, and then apply ten-
sion to timing chain.
c. Install chain tensioner cover onto front cover. (RH bank)

Apply liquid gasket as shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Products and Seal-
ants" .
7. Check and adjust valve clearances. Refer to EM-52, "
Va l v e
Clearance" .
8. Installation of the remaining components is in the reverse order
of removal.
Va lv e C le a ra n c eEBS00ILO
INSPECTION
NOTE:
Perform inspection as follows 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 engine. Then stop engine.
2. Remove engine cover, battery cover and air duct. Refer to EM-11, "
Removal and Installation" , SC-9,
"REMOVAL" and EM-14, "Removal and Installation" .
3. Remove right bank and left bank rocker covers using power tool. Refer to EM-33, "
Removal and Installa-
tion" .
KBIA2480E
Chain tensioner bolts : 6.9 N·m (0.70 kg-m, 61 in-lb)
Tensioner cover bolts : 9.0 N·m (0.92 kg-m, 80 in-lb)KBIA2479E
KBIA2547E

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)

CYLINDER HEAD
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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

ENGINE ASSEMBLY
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5. Remove the cowl extension. Refer to EI-18, "Removal and Installation" .
6. Remove engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly. Refer to EM-14, "
REMOVAL" .
8. Disconnect vacuum hose between vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-10, "
REMOVAL" .
10. Remove the drive belts. Refer to EM-12, "
Removal" .
11. Remove the fan blade. Refer to CO-13, "
REMOVAL" .
12. Disconnect the engine room harness from the fuse box and set it aside for easier work.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside for easier work.
15. Disconnect the engine harness grounds.
16. Disconnect the reservoir tank for power steering from engine and move it aside for easier work.
17. Disconnect power steering oil pump from engine. Move it from its location and secure with a rope for eas-
ier work. Refer to PS-26, "
REMOVAL" .
18. Remove the A/C compressor bolts and set aside. Refer to ATC-166, "
REMOVAL" .
19. Disconnect brake booster vacuum line.
20. Disconnect EVAP line.
21. Disconnect the fuel hose at the engine side connection. Refer to EM-29, "
REMOVAL" .
22. Disconnect the heater hoses at cowl, and install plugs to avoid leakage of engine coolant.
23. Remove the A/T oil level indicator and indicator tube upper bolts.
24. Remove the A/T. Refer to AT-255, "
Removal and Installation (4x2)" , or AT-258, "Removal and Installation
(4x4)" .
25. Install engine slingers into left bank cylinder head and right bank
cylinder head.
26. Lift with hoist and secure the engine in position.
27. Remove engine assembly from vehicle, avoiding interference
with vehicle body.
CAUTION:

Before and during this lifting, always check if any har-
nesses are left connected.
28. Remove alternator. Refer to SC-27, "
REMOVAL" .
29. Remove engine mounting insulator and bracket using power tool.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:

When replacing an engine or transmission you must make sure the dowels are installed correctly
during re-assembly.

Improper alignment caused by missing dowels may cause vibration, oil leaks or breakage of driv-
etrain components.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
PBIC1556E

EM-72Revision: August 2007
ENGINE ASSEMBLY
2004 QX56
INSPECTION AFTER INSTALLATION

Before starting engine, check the levels of engine coolant, engine oil and working fluid. If less than
required quantity, fill to the specified level.

Use procedure below to check for fuel leakage.

Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.

Start engine. With engine speed increased, check again for fuel leakage at connection points.

Run engine to check for unusual noise and vibration.

Warm up engine thoroughly to make sure there is no leakage of engine coolant, engine oil, working fluid,
fuel and exhaust gas.

Bleed air from passages in pipes and tubes of applicable lines, such as in cooling system.

After cooling down engine, again check amounts of engine coolant, engine oil and working fluid. Refill to
specified level, if necessary.

Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Working fluid* Level Leakage Level
Fuel — Leakage —
Exhaust gas — Leakage —

CYLINDER BLOCK
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d. Remove the main bearing cap.

Insert bolts (2) into bolt holes, and then remove main bearing
cap by lifting up and shaking forward and backward.
15. Remove the crankshaft.
16. Remove the main bearings and thrust bearings from the cylinder block and main bearing caps.

When removing them, note the installation position. Keep them in the correct order.
17. Remove the pilot converter using Tool if necessary.
ASSEMBLY
1. Fully air-blow the coolant and oil passages in the cylinder block, cylinder bore, and crankcase to remove
any foreign material.
CAUTION:
Use goggles to protect your eyes.
2. Install each plug to the cylinder block (only screw-type plugs are
shown).

Apply liquid gasket.
Use Genuine Thread Sealant or equivalent. Refer to GI-
45, "Recommended Chemical Products and Sealants".

Replace the copper washers with new ones.

Tighten each plug as specified below.
3. Install the main bearings and thrust bearings.
a. Remove dust, dirt, and oil on the bearing mating surfaces of the
cylinder block and main bearing caps.
b. Install the thrust bearings to both sides of the No. 3 journal hous-
ing on the cylinder block and main bearing caps

Install the thrust bearings with the oil groove facing the crank-
shaft arm (outside).

Install the thrust bearings with a protrusion in the center on
the main bearing caps.
KBIA2492E
Tool number : ST16610001 (J-23907)
WBIA0596E
Part Washer Tightening torque
A Yes 53.9 N·m (5.5 kg-m, 40 ft-lb)
B No 19.6 N·m (2.0 kg-m, 15 ft-lb)
C Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
D Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
WBIA0419E
PBIC0093E

EM-82Revision: August 2007
CYLINDER BLOCK
2004 QX56
19. Install drive plate.

Align dowel pin of crankshaft rear end with pin holes of each
parts to install.

Install drive plate, reinforcement plate and pilot converter (if
not installed in step 4) as shown.

Face chamfered or rounded edge side to crankshaft.
How to Select Piston and Bearing EBS00ILY
DESCRIPTION
*For the service parts, the grade for fitting cannot be selected between a piston pin and a connecting rod.
(Only 0 grade is available.) The information at the shipment from the plant is described as a reference.

The identification grade stamped on each part is the grade for the dimension measured in new condition.
This grade cannot apply to reused parts.

For reused or repaired parts, measure the dimension accurately. Determine the grade by comparing the
measurement with the values of each selection table.

For details of the measurement method of each part, the reuse standards, and the selection method of the
selective fitting parts, refer to the text.
KBIA2494E
KBIA2537E
Connecting points Connecting parts Selection items Selection methods
Between cylinder block to
crankshaftMain bearingMain bearing grade (bearing
thickness)Determined by match of cylin-
der block bearing housing
grade (Housing inside diame-
ter) and crankshaft journal
grade (journal outside diame-
ter)
Between crankshaft to connect-
ing rodConnecting rod bearingConnecting rod bearing grade
(bearing thickness)Connecting rod bearing grade
= crankshaft pin grade (pin
diameter). No grade exists for
inside diameter of connecting
rod large end.
Between cylinder block to pis-
tonPiston and piston pin assembly.
The piston is available together
with piston pin as an assembly.Piston grade (piston diameter)Piston grade = cylinder bore
grade (diameter of bore)
*Between piston to connecting
rod———