2007 INFINITI QX56 engine

EM-82
< SERVICE INFORMATION >
CYLINDER BLOCK
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 Product and Sealant".
• 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.
4. Install pilot converter to the crankshaft using suitable tool.
5. Install crankshaft to the cylinder block.
• While turning crankshaft by hand, make sure it turns smoothly.
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
PBIC0094E
EMP0569D

CYLINDER BLOCK
EM-83
< SERVICE INFORMATION >
C
D
E
F
G
H
I
J
K
L
MA
EM
N
P O
6. Install main bearing caps.
• Align the identification number to the journal position to install.
• Install it with the front mark (indicated by the arrow) facing the
front of engine.
• Tap caps lightly to seat them in the installation position.
7. Follow the steps below to tighten each main bearing cap bolt.
a. Apply engine oil to threads and seating surfaces of bolts, and
tighten all bolts temporarily.
b. Measure tightening angle using Tool.
CAUTION:
Measure tightening angle using Tool. Do not measure visu-
ally.
• Rotate crankshaft by hand after bolts are tightened. Check if it rotates smoothly.
• Check crankshaft side clearance. Refer to EM-93, "
Inspection After Disassembly".
8. Install rear oil seal to rear oil seal retainer.
CAUTION:
Do not damage or scratch outer circumference of oil seal.
• Install new rear oil seal in the direction shown.
KBIA2533E
Main bearing cap bolts in
order of 1 to 10: 39.2 N·m (4.0 kg-m, 29 ft.-lb)
Main bearing cap sub
bolts in order of 11 to 20: 29.4 N·m (3.0 kg-m, 22 ft-lb)
PBIC0090E
Tool number : KV10112100 (BT-8653-A)
Main bearing cap bolts in
order of 1 to 10: 40°
Main bearing cap sub bolts
in order of 11 to 20: 30°
Side bolts in order of 21 to
30: 49 N·m (5.0 kg-m, 36 ft-lb)
WBIA0597E
SEM715A

EM-84
< SERVICE INFORMATION >
CYLINDER BLOCK
• Tap until flattened with the front edge of the rear oil seal
retainer using suitable tool.
• Fit the rear oil seal until it is level with the rear end surface of
rear oil seal retainer.
9. Install rear oil seal retainer.
• Apply liquid gasket thoroughly to rear oil seal retainer as
shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Product and Sealant".
• Apply new engine oil on the lips of rear oil seal. Do not touch.
10. Install the piston to the connecting rod.
a. Install the snap ring to the grooves of the piston rear side.
• Insert it fully into the groove to install.
b. Install the piston to the connecting rod.
• Heat piston until piston pin can be pushed in by hand without excess force [approx. 60° to 70 C° (140° to
158 °F)]. From the front to the rear, insert the piston pin into the piston and the connecting rod.
• Assemble so that the front mark on the piston crown and the
oil holes and cylinder No. on the connecting rod are positioned
as shown.
c. Install the snap ring to the grooves of the piston front side.
• Insert it fully into the groove to install.
• After installing, make sure connecting rod moves smoothly.
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.
PBIC0097E
SBIA0391E
KBIA2534E
Stamped mark Second ring : 2N
PBIC0100E

CYLINDER BLOCK
EM-85
< SERVICE INFORMATION >
C
D
E
F
G
H
I
J
K
L
MA
EM
N
P O
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 facing
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.
15. Tighten connecting rod bolts using Tool.
• Apply engine oil to threads and seats of connecting rod bolts.
• After tightening bolts, make sure the crankshaft rotates
smoothly.
• Check connecting rod side clearance. Refer to EM-93,
"Inspection After Disassembly".
PBIC0266E
Tool number : EM03470000 (J-8037)
WBIA0626E
KBIA2536E
Tool number : KV10112100 (BT-8653-A)
Connecting rod bolts
Step 1 : 19.6 N·m (1.5 kg-m, 11 ft-lb)
Step 2 : 90° clockwise
WBIA0627E

EM-86
< SERVICE INFORMATION >
CYLINDER BLOCK
16. Install knock sensors.
CAUTION:
If knock sensor is dropped, replace it with a new one.
• Make sure that there is no foreign material on the cylinder
block mating surface and the back surface of knock sensor.
• Install it with its connector facing the center of the cylinder
block side.
• Do not tighten knock sensor bolts while holding connector.
• Make sure knock sensor does not interfere with other parts.
• Position the sub-harness as shown before installing intake
manifold.
17. Installation of the remaining components is in the reverse order of removal.
18. Remove engine assembly from engine stand.
19. Install drive plate.
• Align dowel pin of crankshaft rear end with pin holes of each
part to install.
• Install drive plate, reinforcement plate and pilot converter (if
not installed in step 4) as shown.
• Face the chamfered or rounded edge side to the crankshaft.
How to Select Piston and BearingINFOID:0000000003531546
DESCRIPTION
KBIA2493E
KBIA2549E
KBIA2494E
KBIA2537E

EX-1
ENGINE
C
DE
F
G H
I
J
K L
M
SECTION EX
A
EX
N
O P
CONTENTS
EXHAUST SYSTEM
SERVICE INFORMATION .. ..........................2
PREPARATION .............................................. .....2
Special Service Tool ........................................... ......2
Commercial Service Tool ..........................................2
EXHAUST SYSTEM ...........................................3
Checking Exhaust System ................................... .....3
Removal and Installation ..........................................3

EXHAUST SYSTEMEX-3
< SERVICE INFORMATION >
C
DE
F
G H
I
J
K L
M A
EX
NP
O
EXHAUST SYSTEM
Checking Exhaust SystemINFOID:0000000003532211
Check exhaust pipes, muffler and mounting for improper
attachment, leaks, cracks, damage or deterioration.
• If anything is found, repair or replace damaged parts.
Removal and InstallationINFOID:0000000003532212
Exhaust System
CAUTION:
• Be sure to use genuine exhaust system parts or equivalents which are specially designed for heat
resistance, corrosion resistance, and shape.
• Perform the operation with the exhaust system full y cooled. The system will be hot just after the
engine stops.
• Be careful not to cut your hand on the heat insulator edge.
REMOVAL
SMA211A
WBIA0792E
1. Tailpipe hanger bracket 2. Tailpipe 3. Gasket
4. Main muffler 5. Right front exhaust tube 6. Ring gasket
7. Heated oxygen sensor 2 (bank 1) 8. Heated oxygen sensor 2 (bank 2) 9. Left front exhaust tube
10. Center exhaust tube 11. Muffler hanger bracket front 12. Muffler hanger bracket rear
Front

EX-4
< SERVICE INFORMATION >
EXHAUST SYSTEM
Remove exhaust system components using power tool.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Always replace exhaust gaskets with new ones when reassembling.
• Before installing a new heated oxygen sensor, clean and lube the exhaust tube threads using Tool.
• Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; replace with a new one.
• Do not over-torque the heated oxygen sensor. Doing so may damage the heated oxygen sensor,
resulting in the MIL coming on.
• If any mounting insulator is badly deformed, repair or replace it. If deposits such as mud pile up on
the mounting insulators, clean and inspect them.
• Temporarily tighten the nuts on the exhaust manifold side and the bolts on the vehicle side. Check
each part for interference with other components, and then tighten the nuts and bolts to specifica-
tion.
INSPECTION AFTER INSTALLATION
• With the engine running, check exhaust tube joints for gas leakage and unusual noises.
• Check to ensure that mounting brackets and mounting rubbers are installed properly and free from undue
stress. Improper installation could result in excessive noise and vibration. Tool number
A : — (J-43897-18)
B : — (J-43897-12)