2004 INFINITI QX56 Air

EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION EM
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Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Drain Engine Coolant ...................... 3
Precautions for Disconnecting Fuel Piping .............. 3
Precautions for Removal and Disassembly ............. 3
Precautions for Inspection, Repair and Replace-
ment ......................................................................... 3
Precautions for Assembly and Installation ............... 3
Parts Requiring Angular Tightening ......................... 3
Precautions for Liquid Gasket .................................. 4
REMOVAL OF LIQUID GASKET SEALING .......... 4
LIQUID GASKET APPLICATION PROCEDURE ..... 4
PREPARATION ........................................................... 5
Special Service Tools ............................................... 5
Commercial Service Tools ........................................ 7
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ................................................ 9
NVH Troubleshooting —Engine Noise ..................... 9
Use the Chart Below to Help You Find the Cause
of the Symptom. ..................................................... 10
ENGINE ROOM COVER ...........................................11
Removal and Installation .........................................11
REMOVAL ............................................................11
INSTALLATION ....................................................11
DRIVE BELTS ........................................................... 12
Checking Drive Belts .............................................. 12
Tension Adjustment ................................................ 12
Removal and Installation ........................................ 12
DRIVE BELT ....................................................... 12
INSTALLATION ................................................... 13
Drive Belt Auto Tensioner and Idler Pulley ............. 13
REMOVAL ........................................................... 13
INSTALLATION ................................................... 13
AIR CLEANER AND AIR DUCT ............................... 14
Removal and Installation ........................................ 14
REMOVAL ........................................................... 14
INSTALLATION ................................................... 14
CHANGING AIR CLEANER FILTER ................... 14INTAKE MANIFOLD ................................................. 15
Removal and Installation ........................................ 15
REMOVAL ........................................................... 15
INSTALLATION ................................................... 17
INSPECTION AFTER INSTALLATION ................ 18
EXHAUST MANIFOLD AND THREE WAY CATA-
LYST .......................................................................... 19
Removal and Installation ........................................ 19
REMOVAL ........................................................... 19
INSPECTION AFTER REMOVAL ....................... 20
INSTALLATION ................................................... 20
OIL PAN AND OIL STRAINER ................................. 22
Removal and Installation ........................................ 22
REMOVAL ........................................................... 22
INSPECTION AFTER REMOVAL ....................... 23
INSTALLATION ................................................... 24
INSPECTION AFTER INSTALLATION ................ 25
IGNITION COIL ......................................................... 26
Removal and Installation ........................................ 26
REMOVAL ........................................................... 26
INSTALLATION ................................................... 26
SPARK PLUG (PLATINUM-TIPPED TYPE) ............. 27
Removal and Installation ........................................ 27
REMOVAL ........................................................... 27
INSPECTION AFTER REMOVAL ....................... 27
INSTALLATION ................................................... 28
FUEL INJECTOR AND FUEL TUBE ........................ 29
Removal and Installation ........................................ 29
REMOVAL ........................................................... 29
INSTALLATION ................................................... 30
INSPECTION AFTER INSTALLATION ................ 32
ROCKER COVER ..................................................... 33
Removal and Installation ........................................ 33
REMOVAL ........................................................... 33
INSTALLATION ................................................... 34
TIMING CHAIN .......................................................... 35
Removal and Installation ........................................ 35
REMOVAL ........................................................... 36
INSPECTION AFTER REMOVAL ....................... 39
INSTALLATION ................................................... 39

PRECAUTIONS
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Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Drain Engine CoolantEBS00IKY
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingEBS00IKZ

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 DisassemblyEBS00IL0

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 ReplacementEBS00IL1
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationEBS00IL2

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.

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 TighteningEBS00IL3

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. Tool number : KV10112100 (BT-8653-A)

PREPARATION
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Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolsEBS00IL5
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
KV10111100
(J-37228)
Seal cutterRemoving steel oil pan and rear timing chain
case
KV991J0050
(J-44626)
Air fuel sensor SocketLoosening or tightening air fuel ratio A/F sen-
sor
a: 22 mm (0.87 in)
EG15050500
(J-45402)
Compression gauge adapterInspecting compression pressure
KV10116200
(J-26336-A)
Valve spring compressor
1. KV10115900
(J-26336-20)
Attachment
2. KV10109220
(—)
AdapterDisassembling valve mechanism
Part (1) is a component of KV10116200
(J26336-A), but part (2) is not.
KV10112100
(BT-8653-A)
Angle wrenchTightening bolts for bearing cap and cylinder
head
KV10107902
(J-38959)
Valve oil seal pullerRemoving valve oil seal
S-NT046
LBIA0444E
ZZA1225D
PBIC1650E
S-NT014
S-NT011

EM-10Revision: August 2007
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
2004 QX56
Use the Chart Below to Help You Find the Cause of the Symptom.EBS00IL8
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
A: Closely related B: Related C: Sometimes related —: Not relatedLocation of
noiseType of
noiseOperating condition of engine
Source of
noiseCheck itemRefer-
ence page Before
warm-
upAfter
warm-
upWhen
start-
ingWhen
idlingWhen
racingWhile
driv-
ing
To p o f
engine
Rocker
cover
Cylinder
headTicking or
clickingC A — A B — Tappet noise Valve clearanceEM-52
Rattle C A — A B CCamshaft
bearing noiseCamshaft journal clear-
ance
Camshaft runoutEM-47EM-47
Crankshaft
pulley
Cylinder
block (Side
of engine)
Oil panSlap or
knock—A—B B—Piston pin
noisePiston and piston pin
clearance
Connecting rod bush-
ing clearanceEM-90
EM-92
Slap or
rapA——BBAPiston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsionEM-94EM-90
EM-90
EM-91
Knock ABCBBBConnecting
rod bearing
noiseConnecting rod bush-
ing oil clearance (Small
end)
Connecting rod bear-
ing clearance (Big end)EM-92EM-91
Knock A B — A B CMain bearing
noiseMain bearing oil clear-
ance
Crankshaft runoutEM-96EM-95
Front of
engine
Chain case
cover
Front coverTa p p i n g
or tickingAA—BBBTiming chain
and chain
tensioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operationEM-39
EM-35
Front of
engineSqueak-
ing or
fizzingAB—B—CDrive belts
(Sticking or
slipping)Drive belts deflection
EM-12
CreakingABABABDrive belts
(Slipping)Idler pulley bearing
operation
Squall
CreakingAB—BABWater pum p
noiseWater pump operationCO-15,
"INSPEC-
TION
AFTER
REMOVA
L"

EM-12Revision: August 2007
DRIVE BELTS
2004 QX56
DRIVE BELTSPFP:02117
Checking Drive BeltsEBS00ILA
WAR NIN G:
Be sure to perform when the engine is stopped.
1. Remove the air duct and resonator assembly when inspecting the drive belt. Refer to EM-14, "
Removal
and Installation" .
2. Make sure that the indicator (single line notch) of each auto tensioner is within the allowable working
range (between three line notches).
NOTE:

Check the auto tensioner indication when the engine is cold.

When the new drive belt is installed, the range should be as shown.

The indicator notch is located on the moving side of the auto tensioner.
3. Visually check the entire belt for wear, damage or cracks.
4. If the indicator is out of allowable working range or belt is damaged, replace the belt.
Tension AdjustmentEBS00ILB
Belt tensioning is not necessary, as it is automatically adjusted by the auto tensioner.
Removal and InstallationEBS00ILC
DRIVE BELT
Removal
1. Remove the air duct and resonator assembly. Refer to EM-14, "Removal and Installation" .
2. Install Tool on auto tensioner pulley bolt, move in the direction of
arrow (loosening direction of tensioner) as shown.
CAUTION:
Avoid placing hand in a location where pinching may occur
if the tool accidentally comes off.
3. Remove the drive belt.
LBIA0391E
1. Drive belt 2. Power steering pump pulley 3. Generator pulley
4. Crankshaft pulley 5. A/C compressor 6. Idler pulley
7. Cooling fan pulley 8. Water pump pulley 9. Drive belt tensioner
Tool number : — (J-46535)
WBIA0537E

DRIVE BELTS
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Revision: August 20072004 QX56
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
Make sure belt is securely installed around all pulleys.

Rotate the crankshaft pulley several turns clockwise to equalize belt tension between pulleys.

Make sure belt tension is within the allowable working range, using the indicator notch on the auto ten-
sioner. Refer to EM-12, "
Checking Drive Belts" .
Drive Belt Auto Tensioner and Idler PulleyEBS00ILD
REMOVAL
1. Remove the air duct and resonator assembly. Refer to EM-14, "Removal and Installation" .
2. Remove the drive belt. Refer to EM-12, "
Checking Drive Belts" .
3. Remove the auto tensioner and idler pulley using power tool.
INSTALLATION
Installation is in the reverse order of removal.
WBIA0607E
1. Auto tensioner 2. Idler pulley

EM-14Revision: August 2007
AIR CLEANER AND AIR DUCT
2004 QX56
AIR CLEANER AND AIR DUCTPFP:16500
Removal and InstallationEBS00ILE
REMOVAL
1. Remove the engine room cover using power tool. Refer to EM-14, "REMOVAL" .
2. Disconnect the harness connector from the air cleaner case (upper).
3. Remove the air duct and resonator assembly and air cleaner case.

Add marks as necessary for easier installation.
INSTALLATION
Installation is in the reverse order of removal.
CHANGING AIR CLEANER FILTER
1. Remove the air duct and resonator assembly and air cleaner case (upper).
2. Remove the air cleaner filter from the air cleaner case.
3. Installation is in the reverse order of removal.
1. Air cleaner case (upper) 2. Air cleaner filter 3. Air cleaner case (lower)
4. Air duct and resonator assembly
WBIA0465E

INTAKE MANIFOLD
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INTAKE MANIFOLDPFP:14003
Removal and InstallationEBS00ILF
REMOVAL
1. Partially drain the engine coolant. Refer to MA-12, "DRAINING ENGINE COOLANT" .
WAR NIN G:
To avoid the danger of being scalded, never drain the engine coolant when the engine is hot.
2. Remove the engine room cover using power tool. Refer to EM-11, "
REMOVAL" .
3. Release the fuel pressure. Refer to EC-46, "
FUEL PRESSURE RELEASE" .
4. Remove the air duct and resonator assembly. Refer to EM-14, "
REMOVAL" .
5. Disconnect the fuel tube quick connector on the engine side.
1. Intake manifold 2. PCV hose 3. Gasket
4. Electric throttle control actuator 5. Water hose 6. Water hose
7. PCV hose 8. EVAP hose 9. EVAP canister purge control sole-
noid valve
10. Bracket 11. Gasket
KBIA2461E
LBIA0395E