PRECAUTIONSEM-3
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Revision: November 2009 2006 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EBS00REI
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER ”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Drain Engine CoolantEBS00REJ
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingEBS00REK
Before starting work, make sure no fire or spark producing items are in the work area.
Release fuel pressure before disconnecting and disassembly.
After disconnecting pipes, plug openings to stop fuel leakage.
Precautions for Removal and DisassemblyEBS00REL
When instructed to use special service tools, use the specified tools. Always be careful to work safely,
avoid forceful or uninstructed operations.
Exercise maximum care to avoid damage to mating or sliding surfaces.
Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.
Mark and arrange disassembly parts in an organized way for easy troubleshooting and assembly.
When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally
opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be
used where noted in the step.
Precautions for Inspection, Repair and ReplacementEBS00REM
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationEBS00REN
Use torque wrench to tighten bolts or nuts to specification.
When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is speci-
fied, do exactly as specified.
Replace with new gasket, packing, oil seal or O-ring.
Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for
any restriction and blockage.
Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust.
Before assembly, oil sliding surfaces well.
Release air within route when refilling after draining engine coolant.
EM-4Revision: November 2009
PRECAUTIONS
2006 QX56
Before starting engine, apply fuel pressure to fuel lines with turning ignition switch ON (with engine
stopped). Then make sure that there are no leaks at fuel line connections.
After repairing, start engine and increase engine speed to check engine coolant, fuel, oil, and exhaust
systems for leakage.
Parts Requiring Angular TighteningEBS00REO
For final tightening of the following engine parts use Tool:
–Cylinder head bolts
–Main bearing cap bolts
–Connecting rod cap bolts
–Crankshaft pulley bolt (No angle wrench is required as the bolt flange is provided with notches for angle
tightening)
Do not use a torque value for final tightening.
The torque value for these parts are for a preliminary step.
Ensure thread and seat surfaces are clean and lightly coated with engine oil.
Precautions for Liquid GasketEBS00REP
REMOVAL OF LIQUID GASKET SEALING
After removing the bolts and nuts, separate the mating surface
and remove the old liquid gasket sealing using Tool.
CAUTION:
Do not damage the mating surfaces.
Tap the seal cutter to insert it.
In areas where the Tool is difficult to use, lightly tap to slide it.
LIQUID GASKET APPLICATION PROCEDURE
1. Remove the old liquid gasket adhering to the gasket applicationsurface and the mating surface using suitable tool.
Remove the liquid gasket completely from the groove of the
liquid gasket application surface, bolts, and bolt holes.
2. Thoroughly clean the mating surfaces and remove adhering moisture, grease and foreign material.
3. Attach the liquid gasket tube to the Tool. Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-46, "
Recommended Chemical Products and Sealants" .
4. Apply the liquid gasket without breaks to the specified location with the specified dimensions.Tool number : KV10112100 (BT-8653-A)
Tool number : KV10111100 (J-37228)
WBIA0566E
PBIC0003E
Tool number : WS39930000 ( — )
WBIA0567E
EM-20Revision: November 2009
INTAKE MANIFOLD
2006 QX56
5. Install the quick connector cap on the quick connector joint (onengine side only).
6. Install the fuel hose and tube to hose clamps.
7. Refill the engine coolant. Refer to CO-11, "
REFILLING ENGINE
COOLANT" .
INSPECTION AFTER INSTALLATION
After installing fuel tubes, make sure there is no fuel leakage at connections in the following steps.
–Apply fuel pressure to fuel lines by turning ignition switch ON (with engine stopped). Then check for fuel
leaks at connections.
–Start the engine and rev it up and check for fuel leaks at the connections.
Perform procedures for “Throttle Valve Closed Position Learning ” after finishing repairs. Refer to EC-78,
"Throttle Valve Closed Position Learning" .
If electric throttle control actuator is replaced, perform procedures for “Idle Air Volume Learning” after fin-
ishing repairs. Refer to EC-78, "
Idle Air Volume Learning" .
SBIA0354E
OIL PAN AND OIL STRAINEREM-27
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Revision: November 2009 2006 QX56
b. Tighten the oil pan (lower) bolts in numerical order as shown.
4. Install the oil pan drain plug.
5. Install engine assembly. Refer to EM-76, "
INSTALLATION" .
Do not fill the engine oil for at least 30 minutes after oil pan is installed.
INSPECTION AFTER INSTALLATION
1. Check engine oil level and add engine oil if necessary. Refer to LU-7, "OIL LEVEL" .
2. Start the engine, and check for leaks of engine oil.
3. Stop engine and wait for 10 minutes.
4. Check engine oil level again.
PBIC2595E
EM-34Revision: November 2009
FUEL INJECTOR AND FUEL TUBE
2006 QX56
Make sure that O-ring and its mating part are free of foreign material.
When installing O-ring, be careful not to scratch it with tool or fingernails. Also be careful not to
twist or stretch O-ring.
If O-ring was stretched while it was being attached, do not insert it quickly into fuel tube.
Insert new O-ring straight into fuel tube. Do not twist it.
6. Installation of the remaining components is in the reverse order of removal.
INSPECTION AFTER INSTALLATION
After installing the fuel tubes, make sure there are no fuel leaks at the connections using the following steps.
1. Apply fuel pressure to the fuel lines by turning ignition switch ON (with engine stopped). Then check for fuel leaks at the connections.
NOTE:
Use mirrors for checking on hidden points.
2. Start the engine and rev it up and check for fuel leaks at the connections.
CAUTION:
Do not touch the engine immediately after stopping, as engine becomes extremely hot.
EM-40Revision: November 2009
TIMING CHAIN
2006 QX56
9. Remove the oil pump. Refer to LU-13, "REMOVAL" .
10. Remove the chain tensioner on the LH bank using the following steps.
NOTE:
To remove the timing chain and associated parts, start with those on the LH bank. The procedure for
removing parts on the RH bank is omitted because it is the same as that for the LH bank.
a. Squeeze the return-proof clip ends using suitable tool and push the plunger into the tensioner body.
b. Secure the plunger using stopper pin.
Stopper pin is made from hard wire approximately 1 mm (0.04
in) in diameter.
c. Remove the bolts and chain tensioner. WARNING:
Plunger, spring, and spring seat pop out when (squeezing)
return-proof clip without holding plunger head. It may
cause serious injuries. Always hold plunger head when
removing.
NOTE:
Stop the plunger in the fully extended position by using the
return-proof clip 1 if the stopper pin is removed.
Push the plunger 2 into the tensioner body while squeezing
the return-proof clip 1. Secure it using stopper pin 3.
11. Remove the timing chain tension guide and timing chain slack guide.
12. Remove the timing chain and crankshaft sprocket.
13. Loosen the camshaft sprocket bolts as shown and remove the camshaft sprocket.
CAUTION:
To avoid interference between valves and pistons, do not
turn crankshaft or camshaft when timing chain is discon-
nected.
14. Repeat the same procedure to remove the RH timing chain and associated parts.
INSPECTION AFTER REMOVAL
Check for cracks and any excessive wear at link plates. Replace
chain if necessary.
In the same way as for the LH bank, inspect the timing chain
and associated parts on the RH bank.
KBIA2479E
KBIA2483E
KBIA2513E
PBIC0282E
CAMSHAFTEM-55
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Revision: November 2009 2006 QX56
5. Install the camshaft sprockets using the following procedure:
A: LH bank shown
a. Install the camshaft sprockets aligning them with the matching marks painted (B) on the timing chain (C) when removed. Align
the camshaft sprocket key groove with the dowel pin on the
camshaft front edge at the same time. Then temporarily tighten
camshaft sprocket 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.)
A: Intake (I)
B: Exhaust (E)
R: for RH bank
L: for LH bank
b. Lock the hexagonal part of the camshaft in the same way as for removal, and tighten the camshaft sprocket bolts.
c. Check again that the timing alignment mark on the timing chain and on each sprocket are aligned.
6. Install the chain tensioner using the following procedure: NOTE:
LH 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 RH bank timing chain tensioner cover onto the front cover.
Apply liquid gasket as shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-46, "
Recommended Chemical Products and Sealants"
.
7. Check and adjust valve clearances. Refer to EM-55, "
Va l v e
Clearance" .
8. Installation of the remaining components is in the reverse order of removal.
Va l v e C l e a r a n c eEBS00RF9
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).
WBIA0712E
WBIA0700E
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
CYLINDER HEADEM-63
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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