Nissan Murano Z50 (2003 year). Manual — part 131
CYLINDER BLOCK
EM-105
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2.
Install each plug to the cylinder block.
●
Apply liquid gasket.
Use Genuine Thread Sealant or equivalent. Refer to
"RECOMMENDED CHEMICAL PRODUCTS AND SEAL-
ANTS"
3.
Install oil jet.
●
Insert oil jet dowel pin into the cylinder block dowel pin hole,
and tighten the mounting bolts.
4.
Install the main bearings and the thrust bearings.
a.
Remove dust, dirt, and oil on the bearing mating surfaces of the
cylinder block and the main bearing cap.
b.
Install the thrust bearings to the both sides of the No. 3 journal
housing on the cylinder block and the main bearing cap.
●
Install the thrust bearings with the oil groove facing the crank-
shaft arm (outside).
●
Install bearing with a projection on one end on cylinder block,
and bearing with a projection at center on cap. Align each pro-
jection with mating notch.
c.
Install the main bearings paying attention to the direction.
●
The main bearing with an oil hole and groove goes on the cyl-
inder block. The one without them goes on the main bearing
cap.
●
Before installing the bearings, apply engine oil to the bearing
surface (inside). Do not apply oil to the back surface, but thor-
oughly clean it.
●
When installing, align the bearing stopper to the notch.
●
Ensure the oil holes on cylinder block and those on the corre-
sponding bearing are aligned.
Part
Washer
Tightening torque
A
No
7.8 - 11.8 N·m (0.8 - 1.2 kg-m, 69 - 104 in-lb)
B
Yes
24.5 - 29.4 N·m (2.5 - 2.9 kg-m, 18 - 21 ft-lb)
C
Yes
59 - 65 N·m (6.1 - 6.7 kg-m, 44 - 48 ft-lb)
PBIC1269E
PBIC0898E
PBIC0807E
SEM175F
EM-106
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
5.
Install the crankshaft to the cylinder block.
●
While turning the crankshaft by hand, check that it turns
smoothly.
6.
Install main bearing cap.
●
Main bearing caps are identified by identification mark cast on
them. For installation, face front mark to front side.
NOTE:
Main bearing cap cannot be replaced as a single part,
because it is machined together with cylinder block.
7.
Install main bearing beam.
●
Install main bearing beam with front mark facing downward
(oil pan side).
●
Install main bearing beam with front mark facing front of
engine.
8.
Inspect outer diameter of main bearing cap bolt. Refer to
123, "OUTER DIAMETER OF MAIN BEARING CAP BOLT"
.
9.
Install main bearing cap bolt.
a.
Apply new engine oil to threads and seat surfaces of mounting
bolts.
b.
Tighten bolts in numerical order with tightening torque 32.3 to
38.3 N·m (3.3 to 3.9 kg-m, 24 to 28 ft-lb) in several different
steps.
c.
Turn all bolts another 90 to 95 degrees clockwise [Target: 90
degrees (Angle tightening)].
CAUTION:
Use an angle wrench [special service tool: KV10112100
(BT8653-A)] to check tightening angle. Do not make judg-
ment by visual inspection.
●
After installing mounting bolts, make sure that crankshaft can
be rotated smoothly by hand.
●
Check crankshaft side clearance. Refer to
10. Inspect outer diameter of connecting rod bolt. Refer to
"OUTER DIAMETER OF CONNECTING ROD BOLT"
11. Install the piston to the connecting rod.
a.
Using a snap ring pliers, install a new snap ring to the groove of the piston rear side.
●
Insert it fully into groove to install.
b.
Install the piston to the connecting rod.
●
Using an industrial drier or similar tool, heat the piston until the piston pin can be pushed in by hand
without excess force [approx. 60 to 70
°
C (140 to 158
°
F)]. From the front to the rear, insert the piston
pin into the piston and the connecting rod.
SEM456G
PBIC0881E
SEM851E
PBIC0921E
CYLINDER BLOCK
EM-107
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Assemble so that the front mark on the piston crown and the
cylinder number on the connecting rod are positioned as
shown in the figure.
c.
Install a new snap ring to the groove of the piston front side.
●
Insert it fully into groove to install.
●
After installing, check that the connecting rod moves
smoothly.
12. Using a piston ring expander (commercial service tool), install the piston rings.
●
If there is stamped mark on ring, mount it with marked side
up.
NOTE:
If there is no stamp on ring, no specific orientation is required
for installation.
CAUTION:
Be careful not to damage the piston.
●
Position each ring with the gap as shown in the figure refer-
ring to the piston front mark.
13. Install the connecting rod bearings to the connecting rod and the
connecting rod cap.
●
When installing the connecting rod bearings, apply engine oil
to the bearing surface (inside). Do not apply oil to the back
surface, but thoroughly clean it.
●
When installing, align the connecting rod bearing stopper pro-
trusion with the cutout of the connecting rod to install.
●
Check the oil hole on the connecting rod and that on the cor-
responding bearing are aligned.
SEM838F
Stamped mark:
Top ring
: —
Second ring
: R
SEM757G
PBIC0808E
PBIC0266E
EM-108
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
14. Install the piston and connecting rod assembly to the crankshaft.
●
Position the crankshaft pin corresponding to the connecting
rod to be installed onto the bottom dead center.
●
Apply engine oil sufficiently to the cylinder bore, piston and
crankshaft pin.
●
Match the cylinder position with the cylinder number on the
connecting rod to install.
●
Be sure that front mark on piston crown is facing front of
engine.
●
Using a piston ring compressor (special service tool) or suit-
able tool, install the piston with the front mark on the piston
crown facing the front of the engine.
CAUTION:
Be careful not to damage the cylinder wall and crankshaft pin, resulting from an interference of
the connecting rod big end.
15. Install the connecting rod cap.
●
Match the stamped cylinder number marks on the connecting
rod with those on the cap to install.
●
Be sure that front mark on connecting rod cap is facing front
of engine.
16. Tighten the connecting rod bolt as follows.
a.
Apply engine oil to the threads and seats of the connecting rod
bolts.
b.
Tighten bolts to 18.6 to 20.6 N·m (1.9 to 2.1 kg-m, 14 to 15 ft-lb).
c.
Then tighten all bolts 90 to 95 degrees clockwise [target: 90
degrees (Angle tightening)].
CAUTION:
Always use an angle wrench [special service tool:
KV10112100 (BT8653-A)]. Avoid tightening based on visual
check alone.
●
After tightening the bolt, make sure that the crankshaft rotates
smoothly.
●
Check the connecting rod side clearance. Refer to
EM-115, "CONNECTING ROD SIDE CLEARANCE"
.
17. Apply liquid gasket and install rear oil seal retainer.
●
Use Genuine RTV Silicone Sealant or equivalent. Refer to
46, "RECOMMENDED CHEMICAL PRODUCTS AND SEAL-
ANTS"
.
CAUTION:
Replace with the new parts.
NOTE:
Rear oil seal with rear oil seal retainer.
SEM620
PBIC0809E
SEM953E
PBIC0922E
CYLINDER BLOCK
EM-109
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18. Install pilot converter using suitable tool.
●
Outer diameter of drift
●
Press-fit pilot converter with its chamfer facing crankshaft.
●
Install pilot converter as shown.
19. Install drive plate.
●
Install drive plate and reinforcement plate as shown in figure.
●
Secure the crankshaft using a suitable ring gear stopper or an
alternative manner.
●
Tighten the installation bolts crosswise over several times.
20. Install knock sensor.
●
Make sure that there is no foreign material on the cylinder
block mating surface and the back surface of the knock sen-
sor.
●
Install knock sensor so that connector faces front of engine.
●
Do not tighten the mounting bolts while holding the connector.
●
Make sure that the knock sensor does not interfere with other-
parts.
CAUTION:
If any impact by dropping is applied to the knock sensor,
replace it with new one.
●
After installing knock sensor, connect sub-harness, and lay it out to rear of engine.
21. Install followings in reverse order of removal.
Pilot converter
: Approx. 33 mm (1.30 in)
PBIC0899E
SEM537E
PBIC0910E
PBIC0810E
EM-110
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
How to Select Piston and Bearing
ABS0033L
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.
HOW TO SELECT PISTON
When New Cylinder Block is Used
●
Check the cylinder bore grade (1, 2, or 3) on rear side of cylinder
block, and select a piston of the same grade.
●
The piston is available with piston pin as a set for the service
part. (Only 0 grade piston pin is available.)
When Cylinder Block is Reused
1.
Measure the cylinder block bore inner diameter. Refer to
119, "Inner Diameter of Cylinder Bore"
2.
Determine the bore grade by comparing the measurement with
the values under the cylinder bore inner diameter of the “Piston
Selection Table”.
3.
Select the piston of the same grade.
Selection points
Selection parts
Selection items
Selection methods
Between cylinder block and
crankshaft
Main bearing
Main bearing grade
(bearing thickness)
Determined by match of cylin-
der block bearing housing
grade (inner diameter of hous-
ing) and crankshaft journal
grade (outer diameter of jour-
nal)
Between crankshaft and con-
necting rod
Connecting rod bearing
Connecting rod bearing grade
(bearing thickness)
Combining service grades for
connecting rod big end inner
diameter and crankshaft pin
outer diameter determine con-
necting rod bearing selection.
Between cylinder block and pis-
ton
Piston and piston pin assembly
(The piston is available
together with piston pin as an
assembly.)
Piston grade
(piston outer diameter)
Piston grade = cylinder bore
grade (inner diameter of bore)
*Between piston and connect-
ing rod
—
—
—
SEM756G
PBIC0812E
CYLINDER BLOCK
EM-111
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Piston Selection Table
Unit: mm (in)
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 piston pin grades can be selected. (Only 0 grade is available.)
●
No second grade mark is available on piston.
HOW TO SELECT CONNECTING ROD BEARING
When New Connecting Rod and Crankshaft are Used
●
Check pin diameter grade number (0, 1, or 2) stamped in front of
crankshaft, and select connecting rod bearing of same grade
number.
NOTE:
There is no grading for connecting rod big end inner diameter.
When Crankshaft and Connecting Rod are Reused
1.
Measure dimensions of the big end inner diameter of connecting rod and outer diameter of crankshaft pin
individually. Refer to
EM-117, "CONNECTING ROD BEARING HOUSING DIAMETER (BIG END)"
and
EM-120, "OUTER DIAMETER OF CRANKSHAFT PIN"
2.
Confirm the big end inner diameter of connecting rod is within the standard value.
3.
Apply the measured dimension to the “Connecting Rod Bearing Selection Table”.
4.
Determine the grade of crankshaft pin diameter grade by comparing the measurement with the values
under the crankshaft pin outer diameter of the “Connecting Rod Bearing Selection Table”.
5.
Select the connecting rod bearing of the same grade.
Connecting Rod Bearing Selection Table
Unit: mm (in)
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 inner diameter with bearing installed, and grind the
crankshaft pin so that the oil clearance satisfies the standard.
Grade
1
2 (or no mark)
3
Inner diameter of cylinder bore
95.500 / 95.510
(3.7598 / 3.7602)
95.510 / 95.520
(3.7602 / 3.7606)
95.520 / 95.530
(3.7606 / 3.7610)
Outer diameter of piston
95.480 / 95.490
(3.7590 / 3.7594)
95.490 / 95.500
(3.7594 / 3.7598)
95.500 / 95.510
(3.7598 / 3.7602)
SEM452G
Connecting rod big end inner diameter (Standard value)
55.000 - 55.013 (2.1654 - 2.1659)
Crankshaft pin outer diameter
Grade (Mark)
— (No grade)
51.968 - 51.974
(2.0460 - 2.0462)
0
Bearing grade No. STD 0
Bearing thickness range: 1.500 - 1.503 (0.00591 - 0.0592)
Color: Black
51.962 - 51.968
(2.0457 - 2.0460)
1
Bearing grade No. STD 1
Bearing thickness range: 1.503 - 1.506 (0.0592 - 0.0593)
Color: Brown
51.956 - 51.962
(2.0455 - 2.0457)
2
Bearing grade No. STD 2
Bearing thickness range: 1.506 - 1.509 (0.0593 - 0.0594)
Color: Green
EM-112
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
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.
“Main Bearing Selection Table” rows correspond to bearing
housing grade on rear left side of cylinder block.
2.
Apply journal diameter grade stamped on crankshaft front side
to columns in “Main Bearing Selection Table”.
3.
Find sign (main bearing grade) at crossing of row and column in
“Main Bearing Selection Table”.
When Cylinder Block and Crankshaft are Reused
1.
Measure inner diameter of cylinder block main bearing housing and outer diameter of crankshaft journal.
Refer to
EM-118, "INNER DIAMETER OF MAIN BEARING HOUSING"
and
2.
Find measured dimension in “Cylinder block bearing housing inner diameter” row of “Main Bearing Selec-
tion Table”.
3.
Find the measured dimension in “Crankshaft main journal diameter” column in the following selection
table.
4.
Select main bearing grade at the point where selected row and column meet in following selection table.
Size
Thickness
US 0.25 (0.0098)
1.626 - 1.634 (0.0640 - 0.0643)
PBIC0813E
SEM756G
SEM452G
CYLINDER BLOCK
EM-113
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Main Bearing Selection Table
PBIC0814E
EM-114
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
Main Bearing Grade Table (All Journals)
Undersize Bearing Usage Guide
●
Use undersize (US) bearing when oil clearance with standard
size main bearing is not within specification.
●
When using undersize (US) bearing, measure the bearing inner
diameter with bearing installed, and grind journal until oil clear-
ance falls within specification.
Bearing undersize table
Unit: mm (in)
CAUTION:
Keep fillet R when grinding crankshaft journal in order to
use undersize bearing (All journals).
Grade number
Thickness “T”
mm (in)
Width “W”
mm (in)
Identification color
(UPR/LWR)
Remarks
0
2.000 - 2.003 (0.0787 - 0.0789)
19.9 - 20.1
(0.783 - 0.791)
Black
Grade is the same for
upper and lower bear-
ings.
1
2.003 - 2.006 (0.0789 - 0.0790)
Brown
2
2.006 - 2.009 (0.0790 - 0.0791)
Green
3
2.009 - 2.012 (0.0791 - 0.0792)
Yellow
4
2.012 - 2.015 (0.0792 - 0.0793)
Blue
5
2.015 - 2.018 (0.0793 - 0.0794)
Pink
6
2.018 - 2.021 (0.0794 - 0.0796)
Purple
7
2.021 - 2.024 (0.0796 - 0.0797)
White
01
UPP
2.003 - 2.006 (0.0789 - 0.0790)
Brown/Black
Grade is different for
upper and lower bear-
ings.
LWR
2.000 - 2.003 (0.0787 - 0.0789)
12
UPR
2.006 - 2.009 (0.0790 - 0.0791)
Green/Brown
LWR
2.003 - 2.006 (0.0789 - 0.0790)
23
UPR
2.009 - 2.012 (0.0791 - 0.0792)
Yellow/Green
LWR
2.006 - 2.009 (0.0790 - 0.0791)
34
UPR
2.012 - 2.015 (0.0792 - 0.0793)
Blue/Yellow
LWR
2.009 - 2.012 (0.0791 - 0.0792)
45
UPR
2.015 - 2.018 (0.0793 - 0.0794)
Pink/Blue
LWR
2.012 - 2.015 (0.0792 - 0.0793)
56
UPR
2.018 - 2.021 (0.0794 - 0.0796)
Purple/Pink
LWR
2.015 - 2.018 (0.0793 - 0.0794)
67
UPR
2.021 - 2.024 (0.0796 - 0.0797)
White/Purple
LWR
2.018 - 2.021 (0.0794 - 0.0796)
Size
Thickness
US 0.25 (0.0098)
2.132 - 2.140 (0.0839 - 0.0843)
PBIC0813E
CYLINDER BLOCK
EM-115
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Inspection After Disassembly
ABS0033M
CRANKSHAFT SIDE CLEARANCE
●
Using a dial gauge, measure the clearance between the thrust
bearings and the crankshaft arm when the crankshaft is moved
fully forward or backward.
●
If the measured value exceeds the limit, replace the thrust bear-
ings, and measure again. If it still exceeds the limit, replace the
crankshaft also.
CONNECTING ROD SIDE CLEARANCE
●
Measure side clearance between connecting rod and crankshaft
arm with feeler gauge.
●
If the measured value exceeds the limit, replace the connecting
rod, and measure again. If it still exceeds the limit, replace the
crankshaft also.
PISTON AND PISTON PIN CLEARANCE
Inner Diameter of Piston Pin
●
Measure the inner diameter of piston pin bore with an inside
micrometer.
Outer Diameter of Piston Pin
●
Measure outer diameter of piston pin with a micrometer.
Piston and Piston Pin Clearance
(Piston pin clearance) = (Piston pin bore diameter) – (Outer diameter of piston pin)
●
If clearance exceeds specification, replace piston/piston pin assembly with reference to specification of
each parts.
Standard
: 0.10 - 0.25 mm (0.0039 - 0.0098 in)
Limit
: 0.30 mm (0.0118 in)
EMQ0196D
Standard
: 0.20 - 0.35 mm (0.0079 - 0.0138 in)
Limit
: 0.40 mm (0.0157 in)
PBIC0815E
Standard
: 21.993 - 22.005 mm (0.8659 - 0.8663 in)
PBIC0116E
Standard
: 21.989 - 22.001 mm (0.8657 - 0.8662 in)
PBIC0117E
Standard
: 0.002 - 0.006 mm (0.0001 - 0.0002 in)
EM-116
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
●
When replacing piston/piston pin assembly, refer to
EM-119, "PISTON TO CYLINDER BORE CLEAR-
.
PISTON RING SIDE CLEARANCE
●
Measure side clearance of piston ring and piston ring groove
with feeler gauge.
●
If out of specification, replace piston and/or piston ring assembly.
PISTON RING END GAP
●
Check if inner diameter of cylinder bore is within specification.
Refer to
EM-119, "PISTON TO CYLINDER BORE CLEAR-
.
●
Insert piston ring until middle of cylinder with piston, and mea-
sure gap.
●
If out of specification, replace piston ring. If gap still exceeds the limit even with a new ring, re-bore cylin-
der and use oversized piston and piston ring.
CONNECTING ROD BEND AND TORSION
●
Check with connecting rod aligner.
Standard:
Top ring
: 0.045 - 0.080 mm (0.0016 - 0.0031 in)
2nd ring
: 0.030 - 0.070 mm (0.0012 - 0.0028 in)
Oil ring
: 0.065 - 0.135 mm (0.0026 - 0.0053 in)
Limit:
Top ring
: 0.11 mm (0.0043 in)
2nd ring
: 0.1 mm (0.004 in)
SEM024AA
Standard:
Top ring
: 0.23 - 0.33 mm (0.0091 - 0.0130 in)
2nd ring
: 0.33 - 0.48 mm (0.0130 - 0.0189 in)
Oil ring
: 0.20 - 0.50 mm (0.0079 - 0.0197 in)
Limit:
Top ring
: 0.54 mm (0.0213 in)
2nd ring
: 0.80 mm (0.0315 in)
Oil ring
: 0.95 mm (0.0374 in)
PBIC0118E
Bend:
Limit : 0.15 mm (0.0059 in) per 100 mm (3.94 in) length
Torsion:
Limit : 0.30 mm (0.0118 in) per 100 mm (3.94 in) length
SEM038F
CYLINDER BLOCK
EM-117
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●
If it exceeds the limit, replace connecting rod assembly.
CONNECTING ROD BEARING HOUSING DIAMETER (BIG END)
●
Install the connecting rod cap without the connecting rod bearing
installed. After tightening the connecting rod bolt to the specified
torque, measure the connecting rod big end inner diameter
using an inside micrometer. Refer to
for
the tightening procedure.
●
If it exceeds the standard, replace the connecting rod.
CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)
Inner Diameter of Connecting Rod (Small End)
●
Measure inner diameter of bushing.
Outer Diameter of Piston Pin
●
Measure outer diameter of piston pin.
SEM003F
Standard
: 55.000 - 55.013 mm (2.1654 - 2.1659 in)
PBIC1641E
Standard
: 22.000 - 22.012 mm (0.8661 - 0.8666 in)
PBIC0120E
Standard
: 21.989 - 22.001 mm (0.8657 - 0.8662 in)
PBIC0117E
EM-118
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
Connecting Rod Bushing Oil Clearance (Small End)
(Connecting rod small end oil clearance) = (Inner diameter of con-
necting rod small end) – (Outer diameter of piston pin)
●
If the measured value exceeds the standard, replace the con-
necting rod assembly and/or piston and piston pin assembly.
●
If replacing the piston and piston pin assembly, refer to
"PISTON TO CYLINDER BORE CLEARANCE"
.
●
If replacing the connecting rod assembly, refer to
CLEARANCE OF CONNECTING ROD BEARING"
.
Factory installed parts grading:
●
Service parts apply only to grade 0.
Unit: mm (in)
CYLINDER BLOCK DISTORTION
●
Using a scraper, remove gasket on the cylinder block surface,
and also remove oil, scale, carbon, or other contamination.
CAUTION:
Be careful not to allow gasket flakes to enter the oil or
engine coolant passages.
●
Measure the distortion on the block upper face at some different
points in 6 directions.
●
If out of the distortion limit, replace the cylinder block.
INNER DIAMETER OF MAIN BEARING HOUSING
●
Install the main bearing caps and main bearing beam with the
main bearings removed, and tighten the mounting bolts to the
specified torque. Refer to
for the tighten-
ing procedure.
●
Using a bore gauge, measure the inner diameter of the main
bearing housing.
●
If out of specification, replace cylinder block and main bearing
caps as an assembly.
NOTE:
Cylinder block cannot be replaced as a single part because it is
machined together with main bearing cap.
Standard
: 0.005 - 0.017 mm (0.0002 - 0.0007 in)
Limit
: 0.030 mm (0.0012 in)
PBIC0809E
Grade
0
1
Connecting rod small end
inner diameter
22.000 - 22.006
(0.8661 - 0.8664)
22.006 - 22.012
(0.8664 - 0.8666)
Piston pin bore diameter
21.993 - 21.999
(0.8659 - 0.8661)
21.999 - 22. 005
(0.8661 - 0.8663)
Piston pin outer diameter
21.989 - 21.995
(0.8657- 0.8659)
21.995 - 22.001
(0.8659 - 0.8662)
PBIC0812E
Limit
: 0.1 mm (0.004 in)
SEM123C
Standard
: 63.993 - 64.017 mm (2.5194 - 2.5203 in)
PBIC1643E
CYLINDER BLOCK
EM-119
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PISTON TO CYLINDER BORE CLEARANCE
Inner Diameter of Cylinder Bore
●
Using a bore gauge, measure cylinder bore for wear, out-of-
round and taper at 6 different points on each cylinder. (X and Y
directions at A, B and C) (Y is in longitudinal direction of engine)
●
If the measured value exceeds the limit, or if there are scratches
and/or seizure on the cylinder inner wall, hone or rebore the
inner wall.
●
An oversize piston is provided. When using an oversize piston,
rebore the cylinder so that the clearance of the piston-to-cylinder
bore satisfies the standard.
Outer Diameter of Piston
●
Measure piston skirt outer diameter using micrometer.
Piston-to-Cylinder Bore Clearance
●
Calculate by outer diameter of piston skirt and inner diameter of cylinder (direction X, position B).
(Clearance) = (Inner diameter of cylinder) – (Outer diameter of piston skirt).
●
If it exceeds the limit, replace piston/piston pin assembly. Refer to
EM-110, "HOW TO SELECT PISTON"
Reboring Cylinder Bore
1.
Cylinder bore size is determined by adding piston-to-cylinder bore clearance to piston diameter “A”.
Standard inner diameter:
95.500 - 95.530 mm (3.7598 - 3.7610 in)
Wear limit:
0.2 mm (0.008 in)
Out-of-round (Difference between X and Y):
0.015 mm (0.0006 in)
Taper limit (Difference between A and C):
0.01 mm (0.0004 in)
Oversize (OS)
: 0.2 mm (0.008 in)
PBIC0923E
SEM843E
Measure point
: Distance from the top 41.0 mm (1.614 in)
Standard
: 95.480 - 95.510 mm (3.7590 - 3.7602 in)
PBIC0125E
Standard
: 0.010 - 0.030 mm (0.0004 - 0.0012 in)
Limit
: 0.08 mm (0.0031 in)
Rebored size calculation: D = A + B - C
where,
D: Bored diameter
A: Piston diameter as measured
B: Piston - to - cylinder bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
EM-120
CYLINDER BLOCK
Revision; 2004 April
2003 Murano
2.
Install main bearing caps and main bearing beam, and tighten to the specified torque. Otherwise, cylinder
bores may be distorted in final assembly.
3.
Cut cylinder bores.
●
When any cylinder needs boring, all other cylinders must also be bored.
●
Do not cut too much out of cylinder bore at a time. Cut only 0.05 mm (0.0020 in) or so in diameter at a
time.
4.
Hone cylinders to obtain specified piston-to-cylinder bore clearance.
5.
Measure finished cylinder bore for out-of-round and taper.
●
Measurement should be done after cylinder bore cools down.
OUTER DIAMETER OF CRANKSHAFT JOURNAL
●
Measure outer diameter of crankshaft journals.
●
If it out of the standard, measure the main bearing oil clearance.
Then use the undersize bearing. Refer to
OUTER DIAMETER OF CRANKSHAFT PIN
●
Measure outer diameter of crankshaft pin.
●
If it out of the standard, measure the connecting rod bearing oil clearance. Then use the undersize bear-
ing. Refer to
EM-121, "OIL CLEARANCE OF CONNECTING ROD BEARING"
OUT-OF-ROUND AND TAPER OF CRANKSHAFT
●
Using a micrometer, measure the dimensions at 4 different
points shown in the figure on each journal and pin.
●
Out-of-round is indicated by the difference in dimensions
between X and Y at A and B.
●
Taper is indicated by the difference in dimension between A and
B at X and Y.
●
If the measured value exceeds the limit, correct or replace the crankshaft.
●
If corrected, measure the bearing oil clearance of the corrected journal or pin. Then select the main bear-
ing or connecting rod bearing. Refer to
EM-122, "OIL CLEARANCE OF MAIN BEARING"
"OIL CLEARANCE OF CONNECTING ROD BEARING"
Standard
: 59.951 - 59.975 mm (2.3603 - 2.3612 in) dia.
PBIC0127E
Standard
: 51.956 - 51.974 mm (2.0455 - 2.0462 in) dia.
Limit:
Out-of-round
(Difference between X and Y)
: 0.002 mm (0.0001 in)
Taper
(Difference between A and B)
: 0.002 mm (0.0001 in)
SEM316A
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