2006 INFINITI QX56 ESP

CYLINDER HEADEM-63
C
DE
F
G H
I
J
K L
M A
EM
Revision: November 2009 2006 QX56
CYLINDER HEADPFP:11041
On-Vehicle ServiceEBS00RFD
CHECKING COMPRESSION PRESSURE
1. Warm up the engine thoroughly. Then stop the engine.
2. Release the fuel pressure. Refer to EC-80, "
FUEL PRESSURE RELEASE" .
CAUTION:
If CONSULT-II is not used to release fuel pressure leave the fuel pump fuse disconnected until
step 7.
3. Remove the spark plug from each cylinder. Refer to EM-29, "
Removal and Installation" .
4. Connect the engine tachometer (not required in use of CONSULT-II).
5. Install the compression tester with Tool into the spark plug hole.
6. With the accelerator pedal fully depressed, turn the ignition switch to “START” for cranking. When the gauge pointer stabi-
lizes, read the compression pressure and engine rpm. Perform
these steps to check each cylinder.
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 the specified range, check the battery liquid for proper gravity. Check the
engine speed again with normal battery gravity.

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

If some cylinders have 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, the piston rings may be worn out or damaged. Check
the piston rings and replace if necessary.
–If the compression pressure remains at a 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 a valve in adjacent cylinders
may be damaged. Inspect and repair as required.
7. Install the components in the reverse order of removal.
8. Start the engine and confirm that it runs smoothly.
9. Perform trouble diagnosis. If DTC appears, erase it. Refer to LAN-26, "
CAN COMMUNICATION" .
Tool number : EG15050500 (J-45402)
Standard
MinimumDeference limit
between cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 200
WBIA0605E

EM-76Revision: November 2009
ENGINE ASSEMBLY
2006 QX56

Loosen the bolts diagonally.
CAUTION:

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

Place the drive plate with the signal plate surface fac-
ing other than downward.

Keep magnetic materials away from the signal plate.
CAUTION:
Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large enough
for supporting the engine weight.

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 the fuel tube and fuel injector assembly. Refer to EM-31, "Removal and Installation" .
–Remove the intake manifold. Refer to EM-17, "Removal and Installation" .
–Remove the ignition coil. Refer to EM-28, "Removal and Installation" .
–Remove the rocker cover. Refer to EM-35, "Removal and Installation" .
–Other removable brackets.
CAUTION:
Before removing the hanging chains, make sure the engine stand is stable and there is no risk of
overturning.
31. Remove the alternator. Refer to SC-25, "
REMOVAL" .
32. Remove the 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.
INSPECTION AFTER INSTALLATION

Before starting the engine, check oil/fluid levels including engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-11, "
Fluids and Lubricants" .

Use procedure below to check for fuel leakage.

Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel
leakage at the 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 fuel, exhaust gas, or any oils/fluids includ-
ing engine oil and engine coolant.

Bleed air from passages in lines and hoses, such as in cooling system.

After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level if necessary.

Summary of the inspection items:
KBIA2491E

CYLINDER BLOCKEM-79
C
DE
F
G H
I
J
K L
M A
EM
Revision: November 2009 2006 QX56
* Refer to GI-46, "Recommended Chemical Products and Sealants" .
DISASSEMBLY
NOTE:
Explained here is how to disassemble with engine stand supporting transmission surface. When using differ-
ent type of engine stand, some steps may be different.
1. Remove engine assembly and mount to engine stand. Refer to EM-74, "
Removal and Installation" .
CAUTION:
Before removing the hanging chains, make sure engine stand is stable and there is no risk of over-
turning.
2. Drain engine oil. Refer to LU-8, "
Changing Engine Oil" .
3. Drain engine coolant by removing the cylinder block drain plugs “A”, “B ”, “C” and “D ” as shown.
4. Remove the following components and associated parts (the parts referred to in step 1 are not included here).

Oil pan (upper and lower) and oil strainer. Refer to EM-24, "Removal and Installation" .

Crankshaft pulley, front cover and timing chain. Refer to EM-37, "Removal and Installation" .

Camshaft. Refer to EM-46, "Removal and Installation" .

Cylinder head. Refer to EM-64, "Removal and Installation" .
5. Remove knock sensor and sub harness.
CAUTION:
Carefully handle sensor, avoiding shocks.
6. Check connecting rod side clearance. Refer to EM-94, "
CONNECTING ROD SIDE CLEARANCE" .
7. Remove piston and connecting rod assembly as follows.
a. Position the crankshaft pin corresponding to the connecting rod to be removed onto bottom dead center.
1. Knock sensor sub-harness 2. Knock sensor 3. Cylinder block
4. Main bearing upper 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 lower 17. Main bearing lower 18. Crankshaft
19. Pilot converter 20. Thrust bearing upper 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
WBIA0419E
KBIA2549E

EM-82Revision: November 2009
CYLINDER BLOCK
2006 QX56
18. Remove 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 removeany 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-
46, "Recommended Chemical Products and Sealants".

Replace copper washers with new ones.

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

Install thrust bearings with the oil groove facing the crankshaft
arm (outside).

Install thrust bearings with a protrusion in the center on the
main bearing caps.
c. Install main bearings paying attention to the direction.

Install the one with oil holes onto the cylinder block and the
one without oil holes onto the main bearing cap.

Before installing bearings, apply engine oil to bearing surface
(inside). Do not apply oil to the back surface, but thoroughly
clean it.

When installing, align the bearing stopper to the notch.

Ensure the oil holes on the cylinder block and those on the
corresponding bearing are aligned. Tool number : ST16610001 (J-23907)
WBIA0596E
Part Washer
Tightening torque
A Yes 53.9 N·m (5.5 kg-m, 40 ft-lb)
BNo 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
PBIC0094E

CYLINDER BLOCKEM-85
C
DE
F
G H
I
J
K L
M A
EM
Revision: November 2009 2006 QX56
11. Install piston rings.
CAUTION:
Do not damage piston.

Position each ring with the gap as shown, referring to the pis-
ton front mark.

Install the second ring with the stamped surface facing
upward.
12. Install the connecting rod bearings to the connecting rod and connecting rod cap.

When installing the connecting rod bearings, apply engine oil
to the bearing surface (inside). Do not apply oil to the back
surface, but thoroughly clean it.

When installing, align the connecting rod bearing stopper pro-
trusion with the cutout of the connecting rod to install.

Check that the oil holes on the connecting rod and those on
the corresponding bearing are aligned.
13. Install the piston and connecting rod assembly to the crankshaft using Tool.

Position the crankshaft pin corresponding to the connecting
rod to be installed onto bottom dead center.

Apply engine oil sufficiently to the cylinder bore, piston, and
crankshaft pin.

Match the cylinder position with the cylinder No. on the con-
necting rod to install.

Install the piston with the front mark on the piston crown fac-
ing the front of the engine.
CAUTION:
Be careful not to damage the crankshaft pin, resulting from an interference of the connecting
rod big end.
14. Install connecting rod cap.

Match the stamped cylinder number marks on the connecting
rod with those on the cylinder cap to install. Stamped mark Second ring : 2N
PBIC0100E
PBIC0266E
Tool number : EM03470000 (J-8037)
WBIA0626E
KBIA2536E

CYLINDER BLOCKEM-97
C
DE
F
G H
I
J
K L
M A
EM
Revision: November 2009 2006 QX56
Piston Pin Diameter

Measure diameter of piston pin using suitable tool.
Connecting Rod Bushing Oil Clearance (Small End)
(Connecting rod small end oil clearance) = (Inside diameter of con-
necting rod small end) – (Piston pin diameter)

If measured value exceeds the standard, replace the connecting
rod assembly and/or piston and piston pin assembly.

If replacing the piston and piston pin assembly, refer to the Table
for Selective Fitting for Piston to select the piston corresponding
to the applicable bore grade of the cylinder block to be used.
Refer to EM-87, "
HOW TO SELECT PISTON" .
Factory installed parts grading:

Only grade 0 is available.
Unit: mm (in)
CYLINDER BLOCK DISTORTION

Remove any oil, scale, gasket, sealant and carbon deposits from the cylinder block surface.
CAUTION:
Do not allow any debris to enter the oil or coolant passages.

Measure block upper face for distortion in six directions as
shown.

If measurement exceeds the limit, replace cylinder block. Standard : 21.989 - 21.995 mm (0.8657 - 0.8659 in)
PBIC0117E
Standard : 0.005 - 0.017 mm (0.0002 - 0.0007 in)
KBIA2536E
Grade
0
Connecting rod bushing inside diameter 22.000 - 22.006
(0.8661 - 0.8664)
Piston pin diameter 21.989 - 21.995
(0.8657 - 0.8659)
Piston pin hole diameter 21.993 - 21.999
(0.8659 - 0.8661)
KBIA2496E
Standard : 0.03 mm (0.0012 in)
Limit : 0.1 mm (0.004 in)
SEM123C

FL-8Revision: November 2009
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
2006 QX56
Disconnect the quick connector as follows:

Hold the sides of the connector, push in tabs and pull out the
tube.

If the connector and the tube are stuck together, push and pull
several times until they start to move. Then disconnect them
by pulling.
CAUTION:

The quick connector can be disconnected when the tabs
are completely depressed. Do not twist the quick connec-
tor more than necessary.

Do not use any tools to disconnect the quick connector.

Keep the resin tube away from heat. Be especially careful
when welding near the tube.

Prevent any acid liquids such as battery electrolyte, from
getting on the resin tube.

Do not bend or twist the resin tube during connection.

Do not remove the remaining retainer on the hard tube (or
the equivalent) except when the resin tube or the retainer
is replaced.

When the resin tube or hard tube, or the equivalent, is
replaced, also replace the retainer with a new one (white
colored retainer).

To keep the quick connector clean and to avoid damage
and contamination from foreign materials, cover the
quick connector with plastic bags or suitable material as
shown.
SFE562A
PBIC1268E
PBIC0163E

FUEL TANKFL-13
C
DE
F
G H
I
J
K L
M A
FL
Revision: November 2009 2006 QX56
CAUTION:

The quick connector can be disconnected when the tabs
are completely depressed. Do not twist the quick connec-
tor more than necessary.

Do not use any tools to disconnect the quick connector.

Keep the resin tube away from heat. Be especially careful
when welding near the tube.

Prevent any acid liquids such as battery electrolyte, from
getting on the resin tube.

Do not bend or twist the resin tube during connection.

Do not remove the remaining retainer on the hard tube (or
the equivalent) except when the resin tube or the retainer
is replaced.

When the resin tube or hard tube, or the equivalent, is
replaced, also replace the retainer with a new one (white
colored retainer).

To keep the quick connector clean and to avoid damage
and contamination from foreign materials, cover the
quick connector with plastic bags or suitable material as
shown.
16. Remove the four bolts and remove the fuel tank shield.
17. Remove the propeller shaft. Refer to PR-8, "
REAR PROPELLER SHAFT" .
18. Disconnect fuel filler hose, and vent hose at the fuel tank side.
19. Remove the fuel tank strap bolts while supporting the fuel tank with a suitable lift jack.
20. Disconnect the EVAP hose from the molded clip in the top of the fuel tank while lowering the fuel tank.
21. Lower the fuel tank using a suitable lift jack and remove it.
PBIC1268E
PBIC0163E
LBIA0387E