EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION EM
A
EM
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-10Revision: August 2007
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
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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"
INTAKE MANIFOLD
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INSTALLATION
Installation is in the reverse order of removal.
Tighten the intake manifold bolts in numerical order as shown.
Install the EVAP canister purge control solenoid valve connector with it facing front of engine.
Tighten the electronic throttle control actuator bolts of the electric throttle control actuator equally and
diagonally in several steps.
After installation perform procedure in EM-18, "INSPECTION AFTER INSTALLATION" .
Install the water hose so that its overlap width for connection is between 27 mm (1.06 in) and 32 mm (1.26
in) (target: 27 mm 1.06 in).
Connecting Quick Connector of Fuel Tube
Install quick connector as follows (the steps are the same for quick connectors on both engine side and vehi-
cle side except for the quick connector cap).
1. Make sure no foreign substances are deposited in and around tube and quick connector, and they are not
damaged.
2. Thinly apply new engine oil around the fuel tube from tip end to the spool end.
3. Align center to insert quick connector straight into fuel tube.
Insert until the paint mark for engagement identification
(white) goes completely inside quick connector so that you
cannot see it from the straight side of the connected part. Use
a mirror to check this where it is not possible to view directly
from the straight side, such as quick connector on vehicle
side.
Insert fuel tube into quick connector until top spool is com-
pletely inside quick connector, and 2nd level spool exposes
right below quick connector on engine side.
CAUTION:
Hold A position in illustration when inserting fuel tube
into quick connector.
Carefully align center to avoid inclined insertion to pre-
vent damage to O-ring inside quick connector.
Insert until you hear a “click” sound and actually feel
the engagement.
To avoid misidentification of engagement with a similar
sound, be sure to perform the next step.
4. Pull quick connector by hand holding A position. Make sure it is completely engaged (connected) so that it
does not come out from fuel tube.
NOTE:
Recommended pulling force is 50 N (5.1 kg, 11.2 lb).
KBIA2462E
PBIC0017E
KBIA0272E
EM-20Revision: August 2007
EXHAUST MANIFOLD AND THREE WAY CATALYST
2004 QX56
c. Remove the air fuel ratio A/F sensors from both left and right
exhaust manifolds using Tool.
CAUTION:
Be careful not to damage the air fuel ratio A/F sensors
Discard any air fuel ratio A/F sensor which has been
dropped from a height of more than 0.5m (19.7 in) onto a
hard surface such as a concrete floor. Replace it with a
new one.
7. Remove the front cross bar.
8. Remove the exhaust manifold (left bank) using the following
steps.
a. Remove the exhaust front tube using power tool. Refer to EX-3,
"Removal and Installation" .
b. Remove the exhaust manifold cover.
c. Loosen the nuts in reverse order shown using power tool.
d. Remove the exhaust studs from positions 2, 4, 6, 8 and remove
the left exhaust manifold.
9. Remove the exhaust manifold (right bank) using the following
steps.
a. Remove the exhaust front tube using power tool. Refer to EX-3,
"Removal and Installation" .
b. Remove the oil level gauge guide. Refer to EM-22, "
OIL PAN
AND OIL STRAINER" .
c. Remove the exhaust manifold cover.
d. Loosen the nuts in reverse order shown using power tool.
e. Remove the exhaust studs from positions 2, 4, 6, 8 and remove the right exhaust manifold.
INSPECTION AFTER REMOVAL
Surface Distortion
Use a reliable straightedge and feeler gauge to check the flat-
ness of each exhaust manifold flange surface.
If flatness exceeds the limit, replace the exhaust manifold.
INSTALLATION
Installation is in the reverse order of removal.
Install a new exhaust manifold gasket with the top of the triangu-
lar up mark on it facing up and its coated face (gray side) toward
the exhaust manifold side.Tool number : — (J-44626)
WBIA0630E
KBIA2464E
Flatness limit : 0.3 mm (0.012 in)
KBIA2504E
KBIA2553E
OIL PAN AND OIL STRAINER
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b. Tighten the oil pan (lower) bolts in numerical order as shown.
4. Install the oil pan drain plug.
5. Installation of the remaining components is in the reverse order of removal.
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 there is no leak of engine oil.
3. Stop engine and wait for 10 minutes.
4. Check engine oil level again.
PBIC2595E
FUEL INJECTOR AND FUEL TUBE
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Handle O-ring with bare hands. Never wear gloves.
Lubricate O-ring with new engine oil.
Do not clean O-ring with solvent.
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 O-ring straight into fuel tube. Do not angle or twist it.
3. Install the fuel injector to the fuel tube using the following steps.
a. Insert new clip into clip mounting groove on the fuel injector.
Insert clip so that lug “A” of fuel injector matches notch “A” of
the clip.
CAUTION:
Do not reuse clip. Replace it with a new one.
Do not allow the clip to interfere with the O-ring. If
interference occurs, replace the O-ring.
b. Insert the fuel injector into the fuel tube with the clip attached.
Insert it while matching it to the axial center.
Insert fuel injector so that lug “B” of fuel tube matches notch
“B” of the clip.
Make sure that the fuel tube flange is securely fixed in the
flange fixing groove on the clip.
c. Make sure that installation is complete by checking that fuel
injector does not rotate or come off.
Make sure that the protrusions of the fuel injectors are aligned
with the cutouts of the clips after installation.
4. Install the fuel tube and fuel injector assembly to the intake manifold.
CAUTION:
Do not let the tip of the injector nozzle come in contact with other parts.
Tighten fuel tube assembly bolts “a” to “b” in illustration in two
steps.
5. Install the fuel hose assembly.
Insert connectors straight, making sure that the axis is lined up with fuel tube side to prevent O-ring
from being damaged.
Tighten the bolts evenly in several steps.
Make sure that there is no gap between the flange and fuel tube after tightening the bolts.
CAUTION:
Handle O-ring with bare hands. Do not wear gloves.Fuel tube side : Blue
Nozzle side : Brown
KBIA2507E
1st step : 12.8 N·m (1.3 kg-m, 9 ft-lb)
2nd step : 24.5 N·m (2.5 kg-m, 18 ft-lb)
KBIA2474E