engine INFINITI QX56 2004 Factory Service Manual

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SQUEAK AND RATTLE TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Tapping or moving the components or pressing on them while driving to duplicate the conditions can isolate
many of these incidents. You can usually insulate the areas with felt cloth tape or insulator foam blocks from
the NISSAN Squeak and Rattle Kit (J-43980) to repair the noise.
TRUNK
Trunk noises are often caused by a loose jack or loose items put into the trunk by the owner.
In addition look for:
1. Trunk lid bumpers out of adjustment
2. Trunk lid striker out of adjustment
3. The trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, securing or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area can often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knocking noise
2. Sun visor shaft shaking in the holder
3. Front or rear windshield touching headliner and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
OVERHEAD CONSOLE (FRONT AND REAR)
Overhead console noises are often caused by the console panel clips not being engaged correctly. Most of
these incidents are repaired by pushing up on the console at the clip locations until the clips engage.
In addition look for:
1. Loose harness or harness connectors.
2. Front console map/reading lamp lens loose.
3. Loose screws at console attachment points.
SEATS
When isolating seat noise it's important to note the position the seat is in and the load placed on the seat when
the noise is present. These conditions should be duplicated when verifying and isolating the cause of the
noise.
Cause of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of these incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.

EI-14
FRONT BUMPER
Revision: August 20072004 QX56
3. Remove engine undercover.
4. Remove fog/turn lamp finisher and fog/turn lamp.

Disconnect harnesses.
5. Remove engine underside cover.
6. Remove fasteners, release clips and remove front fascia assembly.
7. Remove plastic clips and remove upper energy absorber.
8. Remove upper bumper reinforcement.
9. Remove plastic clips and remove lower energy absorber.
10. Remove front bumper stays and front bumper side brackets, LH and RH.
INSTALLATION
Installation is in the reverse order of removal.

EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION EM
A
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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

EM-2Revision: August 20072004 QX56 CAMSHAFT ............................................................... 43
Removal and Installation ........................................ 43
REMOVAL ........................................................... 43
INSPECTION AFTER REMOVAL ........................ 47
INSTALLATION .................................................... 49
Valve Clearance ...................................................... 52
INSPECTION ....................................................... 52
ADJUSTMENT .................................................... 54
OIL SEAL .................................................................. 56
Removal and Installation of Valve Oil Seal ............. 56
REMOVAL ........................................................... 56
INSTALLATION .................................................... 56
Removal and Installation of Front Oil Seal ............. 57
REMOVAL ........................................................... 57
INSTALLATION .................................................... 57
Removal and Installation of Rear Oil Seal .............. 57
REMOVAL ........................................................... 57
INSTALLATION .................................................... 58
CYLINDER HEAD ..................................................... 59
On-Vehicle Service ................................................. 59
CHECKING COMPRESSION PRESSURE ......... 59
Removal and Installation ........................................ 60
REMOVAL ........................................................... 60
INSPECTION AFTER REMOVAL ........................ 61
INSTALLATION .................................................... 61
Disassembly and Assembly .................................... 62
DISASSEMBLY ................................................... 62
ASSEMBLY ......................................................... 63
Inspection After Disassembly ................................. 64
CYLINDER HEAD DISTORTION ........................ 64
VALVE DIMENSIONS .......................................... 65
VALVE GUIDE CLEARANCE .............................. 66
VALVE GUIDE REPLACEMENT ......................... 66
VALVE SEAT CONTACT ..................................... 68
VALVE SEAT REPLACEMENT ........................... 68
VALVE SPRING SQUARENESS ......................... 69
VALVE SPRING DIMENSIONS AND VALVE
SPRING PRESSURE LOAD ............................... 69
ENGINE ASSEMBLY ................................................ 70
Removal and Installation ........................................ 70
REMOVAL ........................................................... 70
INSTALLATION .................................................... 71
INSPECTION AFTER INSTALLATION ................ 72
CYLINDER BLOCK ................................................... 73
Disassembly and Assembly .................................... 73
DISASSEMBLY ................................................... 74ASSEMBLY ..........................................................77
How to Select Piston and Bearing ..........................82
DESCRIPTION ....................................................82
HOW TO SELECT PISTON .................................83
HOW TO SELECT CONNECTING ROD BEAR-
ING .......................................................................84
HOW TO SELECT MAIN BEARING ....................85
Inspection After Disassembly ..................................89
CRANKSHAFT END PLAY ..................................89
CONNECTING ROD SIDE CLEARANCE ...........89
PISTON AND PISTON PIN CLEARANCE ...........89
PISTON RING SIDE CLEARANCE .....................90
PISTON RING END GAP ....................................90
CONNECTING ROD BEND AND TORSION .......91
CONNECTING ROD BEARING (BIG END) ........91
CONNECTING ROD BUSHING OIL CLEAR-
ANCE (SMALL END) ...........................................91
CYLINDER BLOCK DISTORTION ......................92
MAIN BEARING HOUSING INSIDE DIAMETER ...93
PISTON TO CYLINDER BORE CLEARANCE ....93
CRANKSHAFT JOURNAL DIAMETER ...............94
CRANKSHAFT PIN DIAMETER ..........................95
OUT-OF-ROUND AND TAPER OF CRANK-
SHAFT .................................................................95
CRANKSHAFT RUNOUT ....................................95
CONNECTING ROD BEARING OIL CLEAR-
ANCE ...................................................................95
MAIN BEARING OIL CLEARANCE .....................96
CRUSH HEIGHT OF MAIN BEARING ................97
CRUSH HEIGHT OF CONNECTING ROD
BEARING .............................................................97
MAIN BEARING CAP BOLT DIAMETER .............97
CONNECTING ROD BOLT DIAMETER ..............98
SERVICE DATA AND SPECIFICATIONS (SDS) ......99
Standard and Limit ..................................................99
GENERAL SPECIFICATIONS .............................99
DRIVE BELTS ......................................................99
EXHAUST MANIFOLD ........................................99
CAMSHAFT AND CAMSHAFT BEARING ......... 100
CYLINDER HEAD .............................................. 102
CYLINDER BLOCK ............................................ 104
PISTON, PISTON RING AND PISTON PIN ...... 105
CONNECTING ROD .......................................... 105
CRANKSHAFT ................................................... 106
MAIN BEARING ................................................. 107

PRECAUTIONS
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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)

EM-4Revision: August 2007
PRECAUTIONS
2004 QX56
Precautions for Liquid GasketEBS00IL4
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 application
surface 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 materials.
3. Attach the liquid gasket tube to the Tool.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Products and Sealants" .
4. Apply the liquid gasket without breaks to the specified location
with the specified dimensions.

If there is a groove for the liquid gasket application, apply the
liquid gasket to the groove.

As for the bolt holes, normally apply the liquid gasket inside
the holes. If specified in the procedure, it should also be
applied outside the holes.

Within five minutes of liquid gasket application, install the mat-
ing component.

If the liquid gasket protrudes, wipe it off immediately.

Do not retighten after the installation.

Wait 30 minutes or more after installation before refilling the
engine with engine oil and engine coolant.
CAUTION:
If there are specific instructions in this manual, observe them.Tool number : KV10111100 (J-37228)
WBIA0566E
PBIC0003E
Tool number : WS39930000 ( — )
WBIA0567E
SEM 15 9F

NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
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NVH Troubleshooting —Engine NoiseEBS00IL7
KBIA2503E

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"

ENGINE ROOM COVER
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ENGINE ROOM COVERPFP:14049
Removal and InstallationEBS00IL9
REMOVAL

Remove the engine cover bolts and cover.
CAUTION:
Do not damage or scratch cover when installing or remov-
ing.
INSTALLATION
Installation is in the reverse order of removal.
WBIA0464E

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