check engine INFINITI QX4 2005 Factory Service Manual

CAMSHAFT
EM-51
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EM
Revision: October 20052005 QX56
5. Install the camshaft sprockets using the following procedure:
a. Install the camshaft sprockets aligning them with the matching
marks painted on the timing chain when removed. Align the
camshaft sprocket key groove with the dowel pin on the cam-
shaft front edge at the same time. Then temporarily tighten
bolts.

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

Compress the plunger and hold it using a stopper pin when
installing.

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

Apply liquid gasket as shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Products and Sealants"
.
7. Check and adjust valve clearances. Refer to EM-51, "
Va l v e
Clearance" .
8. Installation of the remaining components is in the reverse order
of removal.
Valv e C le aranceEBS00LMA
INSPECTION
NOTE:
Perform the following inspection 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 the engine. Then stop the engine.
2. Remove the engine cover, battery cover and air duct assembly. Refer to EM-11, "
Removal and Installa-
tion" , SC-9, "REMOVAL" and EM-14, "Removal and Installation" .
KBIA2482E
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

EM-54Revision: October 2005
CAMSHAFT
2005 QX56

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 the camshaft. Refer to EM-43, "
Removal and Installation" .
2. Remove the valve lifters at the locations that are out of specification.
3. Measure the center thickness of the removed valve lifters using
suitable tool.
4. Use the equation below to calculate the 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 the camshaft.
7. Manually turn the crankshaft pulley a few turns.
8. Make sure the valve clearances for cold engine are within specifications by referring to the specified val-
ues.
9. After completing the repair, check the valve clearances again with the specifications for a 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-58Revision: October 2005
CYLINDER HEAD
2005 QX56
CYLINDER HEADPFP:11041
On-Vehicle ServiceEBS00LME
CHECKING COMPRESSION PRESSURE
1. Warm up the engine thoroughly. Then stop the engine.
2. Release the fuel pressure. Refer to EC-93, "
FUEL PRESSURE RELEASE" .
CAUTION:
Leave the fuel pump fuse disconnected until step 7.
3. Remove the spark plug from each cylinder. Refer to EM-27, "
REMOVAL" .
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 EC-95, "
TROUBLE DIAGNOSIS" . 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-60Revision: October 2005
CYLINDER HEAD
2005 QX56
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 bolt with a new one.

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

If cylinder head bolts are re-used, check their diameters
before installation. Refer to EM-60, "
Cylinder Head Bolts
Diameter" .
a. Apply engine oil to threads and seating surface of the bolts.
b. Measure the tightening angle using Tool.
CAUTION:
Measure the tightening angle using Tool. Do not measure
visually.
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

EM-70Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
5. Remove the cowl extension. Refer to EI-18, "Removal and Installation" .
6. Remove the engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly EM-14, "
REMOVAL" .
8. Disconnect the vacuum hose between the vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-12, "
REMOVAL" .
10. Remove the drive belts. Refer to EM-12, "
Removal" .
11. Remove the fan blade. Refer to CO-15, "
REMOVAL" .
12. Disconnect the engine room harness from the fuse box and set it aside.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside.
15. Disconnect the engine harness grounds.
16. Disconnect the power steering reservoir tank from the engine and move it aside.
17. Disconnect the power steering oil pump from the engine. Move it aside and secure it using suitable wire or
rope. Refer to PS-26, "
REMOVAL" .
18. Remove the A/C compressor bolts and set the compressor aside. Refer to ATC-179, "
REMOVAL" .
19. Disconnect the brake booster vacuum line.
20. Disconnect the 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 front final drive assembly (4x4 only). Refer to FFD-11, "
REMOVAL" .
25. Remove the exhaust manifolds. Refer to EM-19, "
Removal and Installation" .
26. Install the engine slingers into the left bank cylinder head and
right bank cylinder head.
27. Remove the A/T. Refer to AT-244, "
Removal and Installation
(4x2)" or AT-247, "Removal and Installation (4x4)" .
28. Lift using hoist and secure the engine in position.
29. Remove the engine assembly from the vehicle, avoid interfer-
ence with the vehicle body.
CAUTION:

Before and during lifting, always check if any harnesses
are left connected.
30. Remove the parts that may restrict installation of the engine to the engine stand.
NOTE:
This procedure is described assuming that you use an engine stand mounting to the surface to which the
transmission mounts.
a. Remove the drive plate.

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

Loosen the bolts diagonally.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
PBIC1556E

EM-72Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
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, "
RECOMMENDED 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:
*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
Other oils and fluids* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gas — Leakage —

EM-74Revision: October 2005
CYLINDER BLOCK
2005 QX56
* Refer to GI-45, "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, note steps may be different.
1. Remove engine assembly and mount to engine stand. Refer to EM-69, "
REMOVAL" .
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 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-59, "REMOVAL" .
5. Remove knock sensor.
CAUTION:
Carefully handle sensor, avoiding shocks.
6. Check connecting rod side clearance. Refer to EM-89, "
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.
b. Remove connecting rod cap.
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
WBIA0419E

EM-78Revision: October 2005
CYLINDER BLOCK
2005 QX56
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-89, "CRANKSHAFT END PLAY" .
8. Install rear oil seal to the 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
SEM 71 5A

EM-80Revision: October 2005
CYLINDER BLOCK
2005 QX56
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.
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-89, "CON-
NECTING ROD SIDE CLEARANCE"
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

EX-1
EXHAUST SYSTEM
B ENGINE
CONTENTS
C
D
E
F
G
H
I
J
K
L
M
SECTION EX
A
EX
Revision: October 20052005 QX56 PREPARATION ........................................................... 2
Special Service Tool ................................................. 2
Commercial Service Tools ........................................ 2
EXHAUST SYSTEM ................................................... 3Checking Exhaust System ........................................ 3
Removal and Installation .......................................... 3
REMOVAL ............................................................. 4
INSTALLATION ..................................................... 4
INSPECTION AFTER INSTALLATION .................. 4