service INFINITI QX56 2004 Factory Service Manual

CYLINDER HEAD
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2. Remove the valve guide using suitable tool.
CAUTION:
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
3. Ream cylinder head valve guide hole using suitable tool.
4. Heat cylinder head to 110 to 130°C (230 to 266°F) by soaking in
heated oil.
5. Press valve guide from camshaft side to dimensions as shown.
CAUTION:
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
6. Ream cylinder head valve guide hole using suitable tool.
SEM 93 1C
Valve guide hole diameter:
Standard
Intake and exhaust : 9.975 - 9.996 mm (0.3927 -
0.3935 in)
Oversize (service)
Intake and exhaust : 10.175 - 10.196 mm
(0.4006 - 0.4014 in)
SEM 93 2C
SEM 00 8A
KBIA2530E
Valve guide hole diameter:
Intake and exhaust : 6.000 - 6.018 mm
(0.2362 - 0.2369 in)
SEM 93 2C

EM-68Revision: August 2007
CYLINDER HEAD
2004 QX56
VALVE SEAT CONTACT

After confirming that the dimensions of valve guides and valves
are within specifications, perform this procedure.

Apply prussian blue (or white lead) onto contacting surface of
valve seat to check the condition of the valve contact on the sur-
face.

Check if the contact area band is continuous all around the cir-
cumference.

If not, grind to adjust valve fitting and check again. If the contact-
ing surface still has NG conditions even after the re-check,
replace valve seat.
VALVE SEAT REPLACEMENT
When valve seat is removed, replace with oversized (0.5 mm, 0.020 in) valve seat.
1. Bore out old seat until it collapses. Boring should not continue beyond the bottom face of the seat recess
in cylinder head. Set the machine depth stop to ensure this.
2. Ream cylinder head recess diameter for service valve seat.

Be sure to ream in circles concentric to the valve guide center.

This will enable valve seat to fit correctly.
3. Heat cylinder head to 110 to 130°C (230 to 266°F) by soaking in
heated oil.
4. Provide valve seats cooled well with dry ice. Force fit valve seat into cylinder head.
CAUTION:

Avoid directly touching cold valve seats.

Cylinder head contains heat. When working, wear protective equipment to avoid getting burned.
5. Finish seat to the specified dimensions using suitable tool. Refer
to EM-103, "
Valve Seat" .
CAUTION:
When using valve seat cutter, firmly grip the cutter handle
with both hands. Then, press on the contacting surface all
around the circumference to cut in a single drive. Improper
pressure on the cutter or cutting many different times may
result in stage valve seat.
SBIA0322E
Oversize [0.5 mm (0.020 in)] (Service):
Intake : 38.500 - 38.516 mm (1.5157 - 1.5164 in)
Exhaust : 32.700 - 32.716 mm (1.2874 - 1.2880 in)
SEM 79 5A
SEM 00 8A
SEM 93 4C

EM-82Revision: August 2007
CYLINDER BLOCK
2004 QX56
19. Install drive plate.

Align dowel pin of crankshaft rear end with pin holes of each
parts to install.

Install drive plate, reinforcement plate and pilot converter (if
not installed in step 4) as shown.

Face chamfered or rounded edge side to crankshaft.
How to Select Piston and Bearing EBS00ILY
DESCRIPTION
*For the service parts, the grade for fitting cannot be selected between a piston pin and a connecting rod.
(Only 0 grade is available.) The information at the shipment from the plant is described as a reference.

The identification grade stamped on each part is the grade for the dimension measured in new condition.
This grade cannot apply to reused parts.

For reused or repaired parts, measure the dimension accurately. Determine the grade by comparing the
measurement with the values of each selection table.

For details of the measurement method of each part, the reuse standards, and the selection method of the
selective fitting parts, refer to the text.
KBIA2494E
KBIA2537E
Connecting points Connecting parts Selection items Selection methods
Between cylinder block to
crankshaftMain bearingMain bearing grade (bearing
thickness)Determined by match of cylin-
der block bearing housing
grade (Housing inside diame-
ter) and crankshaft journal
grade (journal outside diame-
ter)
Between crankshaft to connect-
ing rodConnecting rod bearingConnecting rod bearing grade
(bearing thickness)Connecting rod bearing grade
= crankshaft pin grade (pin
diameter). No grade exists for
inside diameter of connecting
rod large end.
Between cylinder block to pis-
tonPiston and piston pin assembly.
The piston is available together
with piston pin as an assembly.Piston grade (piston diameter)Piston grade = cylinder bore
grade (diameter of bore)
*Between piston to connecting
rod———

CYLINDER BLOCK
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HOW TO SELECT PISTON
Piston Selective Fitting When New Cylinder Block is Used:

Check the cylinder bore grade on the bottom face of cylinder
block, and select the piston of the same grade.
When Cylinder Block is Reused
1. Measure the cylinder block bore diameter.
2. Determine the bore grade by comparing the measurement with the values under the “Cylinder bore diam-
eter” of the piston selection table. Use oversized piston if clearance of standard grade piston is outside the
specified value.
Piston Selection Table
Unit: mm (in)
CAUTION:
Oversize must be used in all cylinders when using oversized parts.
NOTE:

The piston is available together with piston pin as an assembly.

The piston pin (piston pin bore) grade is provided only for the parts installed at the plant. For service parts,
no grades can be selected (Only 0 grade is available.).

Hone cylinder to obtain specified clearance between piston and cylinder bore when using an oversized
piston. Be sure to use the same oversized piston rings.
KBIA2495E
KBIA2496E
Grade number (Mark) 1 2 3
Cylinder bore diameter 98.000-98.010 (3.8583-3.8587) 98.010-98.020 (3.8587-3.8590) 93.020-98.030 (3.8590-3.8594)
Piston diameter 97.980-97.990 (3.8575-3.8579) 97.990-98.000 (3.8579-3.8583) 98.000-98.010 (3.8583-3.8587)
Piston oversize (Service) : 0.20 mm (0.0079 in)

CYLINDER BLOCK
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Undersize Bearings Usage Guide

When the specified oil clearance is not obtained with standard size connecting rod bearings, use under-
size (US) bearings.

When using undersize bearing, measure the bearing inside diameter with bearing installed, and grind the
crankshaft pin so that the oil clearance satisfies the standard.
Bearing undersize table
Unit: mm (in)
CAUTION:
In grinding the crankshaft pin to use undersize bearings, keep
the fillet R (All crankshaft pins).
HOW TO SELECT MAIN BEARING
When New Cylinder Block and Crankshaft are Used
1. Apply main bearing housing grade on bottom face of cylinder
block to the row in the "Main Bearings Selection Table".
2. Apply journal diameter grade on crankshaft front to the column
in the "Main Bearings Selection Table".
3. Read the symbol at the cross point of selected row and column in the "Main Bearings Selection Table".
CAUTION:

Initial clearance for No.1, 5 journal and No. 2, 3, 4 journal is different. Use two different selection
lists for each part.

No.1, 5 journal and No. 2, 3, 4 journal have the same signs but different measures. Do not con-
fuse.
4. Apply the symbol to the "Main Bearings Grade Table" to select.
NOTE:

Grade list applies to all journals.

Service parts are available as a set of both upper and lower.
2 1.506 - 1.509 (0.0593 - 0.0594) Green
3 1.509 - 1.512 (0.0594 - 0.0595) Yellow
Undersize Thickness
0.25 (0.0098) 1.627 - 1.635 (0.0641 - 0.0644)
Fillet R : 1.5 - 1.7 mm (0.059 - 0.067 in)
PB I C 0 111E
KBIA2495E
PBIC0 110 E

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CYLINDER BLOCK
2004 QX56
Piston and Piston Pin Clearance
(Piston pin clearance) = (Piston pin hole diameter) – (Piston pin
diameter)

If clearance exceeds specification, replace either or both of pis-
ton/piston pin assembly and connecting rod assembly with refer-
ence to specification of each part.

Refer to piston selection table to replace piston/piston pin
assembly. Refer to EM-83, "
HOW TO SELECT PISTON" .

Refer to connecting rod bearing selection table to replace con-
necting rod. Refer to EM-84, "
HOW TO SELECT CONNECTING
ROD BEARING" .
NOTE:
The connecting rod small end grade and piston pin hole (piston
pin) grade are provided only for the parts installed at the plant.
For service parts, no grades can be selected. (Only 0 grade is
available.)

Refer to EM-92, "Connecting Rod Bushing Oil Clearance (Small
End)" for the values for each grade at the plant.
PISTON RING SIDE CLEARANCE

Measure side clearance of piston ring and piston ring groove
using suitable tool.

If out of specification, replace piston and/or piston ring assembly.
PISTON RING END GAP

Check if diameter of cylinder bore is within specification.
Refer to EM-94, "
Piston to Cylinder Bore Clearance" .

Insert piston ring until middle of cylinder with piston, and mea-
sure gap.Standard : 0.002 - 0.006 mm (0.0001 - 0.0002 in)
KBIA2496E
KBIA2536E
Standard:
Top ring : 0.035 - 0.085 mm (0.0014 - 0.0033 in)
2nd ring : 0.030 - 0.070 mm (0.0012 - 0.0028 in)
Oil ring : 0.015 - 0.050 mm (0.0006 - 0.0020 in)
Limit:
Top ring : 0.11 mm (0.0043 in)
2nd ring : 0.10 mm (0.0039 in)
SEM 02 4AA
Standard:
Top ring : 0.23 - 0.33 mm (0.0091 - 0.0130 in)
2nd ring : 0.25 - 0.40 mm (0.0098 - 0.0157 in)
Oil ring : 0.20 - 0.60 mm (0.0079 - 0.0236 in)
Limit:
Top ring : 0.56 mm (0.0220 in)
2nd ring : 0.52 mm (0.0205 in)
Oil ring : 0.96 mm (0.0378 in)
PBIC0 118 E

CYLINDER BLOCK
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MAIN BEARING HOUSING INSIDE DIAMETER

Install the main bearing caps with the main bearings removed,
and tighten the bolts to the specified torque. Refer to EM-77,
"ASSEMBLY" .

Measure the inside diameter of the main bearing housing.

If out of the standard, replace the cylinder block and main bear-
ing caps as an assembly.
NOTE:
These components must be replaced as a single unit, because
they were processed together.
PISTON TO CYLINDER BORE CLEARANCE
Cylinder Bore Diameter

Measure cylinder bore for wear, out-of-round and taper at six dif-
ferent points on each cylinder ("X" and "Y" directions at "A", "B"
and "C").
NOTE:
When determining cylinder bore grade, measure cylinder bore at
B position.

If the measured value exceeds the repair limit, or if there are
scratches and/or seizure on the cylinder inner wall, hone or bore the inner wall.

An oversize piston is provided. When using an oversize piston, hone the cylinder so that the clearance
between the piston and cylinder satisfies the standard.

If oversize piston is used, use it for all cylinders with oversize piston rings.
Piston Skirt Diameter

Measure piston skirt diameter using suitable tool.Standard : 68.944 - 68.968 mm (2.7143 - 2.7153 in)
PBIC1643E
PBIC0123E
Standard diameter:
98.000 - 98.030 mm (3.8583 - 3.8594 in)
Wear limit:
0.20 mm (0.0079 in)
Out-of-round (Difference between X and Y):
Limit: 0.015 mm (0.0006 in)
Taper limit (Difference between A and C):
Limit: 0.010 mm (0.0004 in)
Piston oversize Grade No. 0 (Service) : 0.20 mm (0.0079 in)
PBIC0124E
Standard : 97. 980 - 98. 010 mm (3.8575 - 3.8587 in)
PBIC0125E

SERVICE DATA AND SPECIFICATIONS (SDS)
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SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Standard and LimitEBS00IM0
GENERAL SPECIFICATIONS
DRIVE BELTS
EXHAUST MANIFOLD
Unit: mm (in) Cylinder arrangementV- 8
Displacement cm
3 (cu in)5,552 (338.80)
Bore and stroke mm (in)98 x 92 (3.86 x 3.62)
Valve arrangementDOHC
Firing order1-8-7-3-6-5-4-2
Number of piston ringsCompression 2
Oil 1
Number of main bearings5
Compression ratio9.8
Compression pressure
kPa (kg/cm
2 , psi)/rpmStandard 1,520 (15.5, 220)/200
Minimum 1,324 (13.5, 192)/200
Differential limit between cylinders 98 (1.0, 14)/200
Cylinder number
Va l v e t i m i n g
Unit: degree
abcde f
232 230 2 48 3 49
SEM 95 7C
PBIC0187E
Tension of drive belts Auto adjustment by auto tensioner
ItemsLimit
Surface distortion Exhaust manifold 0.3 (0.012)

EM-100Revision: August 2007
SERVICE DATA AND SPECIFICATIONS (SDS)
2004 QX56
CAMSHAFT AND CAMSHAFT BEARING
Unit: mm (in)
*: Total indicator reading
Valve Lifter
Unit: mm (in)
Valve Clearance
Unit: mm (in)
*: Approximately 20°C (68 °F) ItemsStandard
Camshaft runout [TIR*] Less than 0.02 (0.0008)
Camshaft cam height “A” Intake & Exhaust 44.465 - 44.655 (1.7506 - 1.7581)
Cam wear limit0.02 (0.0008)
Outside diameter of camshaft journal 25.953 - 25.970 (1.0218 - 1.0224)
Camshaft bracket inside diameter 26.000 - 26.021 (1.0236 - 1.0244)
Camshaft journal clearance 0.030 - 0.068 (0.0012 - 0.0027)
Camshaft end play 0.115 - 0.188 (0.0045 - 0.0074)
Camshaft sprocket runout [TIR*] Less than 0.15 (0.0059)
SEM 67 1
ItemsStandard
Valve lifter diameter 33.977 - 33.987 (1.3377 - 1.3381)
Valve lifter hole diameter 34.000 - 34.016 (1.3386 - 1.3392)
Clearance between lifter and lifter guide 0.013 - 0.039 (0.0005 - 0.0015)
Items Hot Cold * (reference data)
Intake 0.304 - 0.416 (0.012 - 0.016) 0.26 - 0.34 (0.010 - 0.013)
Exhaust 0.308 - 0.432 (0.012 - 0.017) 0.29 - 0.37 (0.011 - 0.015)

SERVICE DATA AND SPECIFICATIONS (SDS)
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Revision: August 20072004 QX56
Available Valve Lifter
Unit: mm (in)
Identification (stamped) Mark Thickness
N788 7.88 (0.3102)
N790 7.90 (0.3110)
N792 7.92 (0.3118)
N794 7.94 (0.3126)
N796 7.96 (0.3134)
N798 7.98 (0.3142)
N800 8.00 (0.3150)
N802 8.02 (03.157)
N804 8.04 (0.3165)
N806 8.06 (0.3173)
N808 8.08 (0.3181)
N810 8.10 (0.3189)
N812 8.12 (0.3197)
N814 8.14 (0.3205)
N816 8.16 (0.3213)
N818 8.18 (0.3220)
N820 8.20 (0.3228)
N822 8.22 (0.3236)
N824 8.24 (0.3244)
N826 8.26 (0.3252)
N828 8.28 (0.3260)
N830 8.30 (0.3268)
N832 8.32 (0.3276)
N834 8.34 (0.3283)
N836 8.36 (0.3291)
SEM 75 8G