2004 INFINITI QX56 engine

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

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 —

EM-74Revision: August 2007
CYLINDER BLOCK
2004 QX56
* Refer to GI-45, "Recommended Chemical Products and Sealants" .
DISASSEMBLY
1. Remove engine assembly. Refer to EM-70, "REMOVAL" .
2. Remove the drive plate.

Hold the crankshaft pulley bolt to lock the crankshaft and remove the drive plate bolts.

Loosen bolts diagonally.
CAUTION:

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

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

Keep magnetic materials away from signal plate.
3. Lift the engine with hoist to install it onto engine stand. Refer to EM-70, "
REMOVAL" .
CAUTION:

Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large
enough for supporting the engine weight.

Before removing the hanging chains, make sure the engine stand is stable and there is no risk
of overturning.

If the load capacity of the stand is not adequate, remove the following parts beforehand to reduce the
potential risk of overturning the stand.
–Remove fuel tube and fuel injector assembly. Refer to EM-29, "REMOVAL" .
–Remove intake manifold. Refer to EM-15, "REMOVAL" .
–Remove exhaust manifold. Refer to EM-19, "REMOVAL" .
–Remove A/C compressor fitting bolts and brackets. Refer to ATC-166, "REMOVAL" .
–Remove ignition coil. Refer to EM-26, "REMOVAL" .
–Remove rocker cover. Refer to EM-33, "REMOVAL" .
–Other removable brackets.
4. Drain engine oil. Refer to MA-16, "
Changing Engine Oil" .
1. Knock sensor sub-harness 2. Knock sensor 3. Cylinder block
4. Main bearing 5. Top ring 6. Second ring
7. Oil ring 8. Crankshaft key 9. Piston
10. Connecting rod 11. Snap ring 12. Piston pin
13. Connecting rod bearing 14. Connecting rod bearing cap 15. Main bearing cap
16. Thrust bearing 17. Main bearing 18. Crankshaft
19. Pilot converter 20. Thrust bearing 21. Side bolt
22. Drive plate 23. Reinforcement plate 24. Rear oil seal retainer
25. Rear oil seal 26. Transmission 27. O-ring
28. Crankshaft position sensor (POS) 29. Gasket 30. Cylinder block heater
31. Connector cap
KBIA2491E

CYLINDER BLOCK
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Revision: August 20072004 QX56
5. Drain engine coolant by removing cylinder block drain plug “A”,
“B”, “C” and “D” as shown.
6. Remove the following components and associated parts (The parts listed in step 3 are not included here.)

Oil pan and oil strainer. Refer to EM-22, "REMOVAL" .

Crankshaft pulley, front cover and timing chain. Refer to EM-36, "REMOVAL" .

Camshaft. Refer to EM-43, "REMOVAL" .

Cylinder head. Refer to EM-60, "REMOVAL" .
7. Remove knock sensor.
CAUTION:
Carefully handle the sensor, avoiding shocks.
8. Remove the piston and connecting rod assembly as follows.

Before removing the piston and connecting rod assembly, check the connecting rod side clearance.
Refer to EM-89, "
CONNECTING ROD SIDE CLEARANCE" .
a. Position the crankshaft pin corresponding to the connecting rod to be removed onto the bottom dead cen-
ter.
b. Remove the connecting rod cap.
c. Push the piston and connecting rod assembly out to the cylinder
head side using suitable tool.
9. Remove the connecting rod bearings.
CAUTION:
When removing them, note the installation position. Keep them in the correct order.
10. Remove the piston rings from the piston using suitable tool.
CAUTION:

When removing the piston rings, be careful not to dam-
age the piston.

Be careful not to damage piston rings by expanding them
excessively.

Before removing the piston rings, check the piston ring side
clearance. Refer to EM-90, "
PISTON RING SIDE CLEARANCE"
.
WBIA0419E
PBIC0086E
PBIC0087E