Nissan Murano. Manual — part 640
EM-134
< UNIT DISASSEMBLY AND ASSEMBLY >
CYLINDER BLOCK
• Measure the inner diameter of connecting rod big end with an
inside micrometer.
• If out of the standard, replace connecting rod assembly.
CONNECTING ROD BUSHING OIL CLEARANCE
Connecting Rod Bushing Inner Diameter
Measure the inner diameter of connecting rod bushing with an inside
micrometer (A).
Piston Pin Outer Diameter
Measure the outer diameter of piston pin with a micrometer (A).
Connecting Rod Bushing Oil Clearance
(Connecting rod bushing oil clearance) = (Connecting rod bushing inner diameter) – (Piston pin outer diame-
ter)
• If the calculated value exceeds the limit, replace connecting rod assembly and/or piston and piston pin
assembly.
• If replacing piston and piston pin assembly, refer to
• If replacing connecting rod assembly, refer to
to select the connecting rod bearing.
1
: Connecting rod
Standard
: Refer to
JPBIA0222ZZ
Standard
: Refer to
JPBIA0223ZZ
Standard
: Refer to
JPBIA0218ZZ
Standard and limit
: Refer to
A
: Sample codes
B
: Bearing stopper groove
C
: Small-end diameter grade
D
: Standard stamp
E
: Weight grade
F
: Cylinder No.
G
: Management code
JPBIA0208ZZ
CYLINDER BLOCK
EM-135
< UNIT DISASSEMBLY AND ASSEMBLY >
C
D
E
F
G
H
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Factory installed parts grading:
• Service parts apply only to grade “0”.
Unit: mm (in)
*: After installing in connecting rod
CYLINDER BLOCK DISTORTION
• Using a scraper, remove gasket on the cylinder block surface, and also remove engine oil, scale, carbon, or
other contamination.
CAUTION:
Be careful not to allow gasket flakes to enter engine oil or engine coolant passages.
• Measure the distortion on the cylinder block upper face at some
different points in six directions (C), (D), (E), (F), (G), and (H) with a
straightedge (A) and a feeler gauge (B).
• If it exceeds the limit, replace cylinder block.
MAIN BEARING HOUSING INNER DIAMETER
• Install main bearing caps and main bearing beam without installing main bearings, and tighten main bearing
cap bolts to the specified torque. Refer to
EM-123, "Disassembly and Assembly"
for the tightening proce-
dure.
• Measure the inner diameter of main bearing housing with a bore
gauge.
• If out of the standard, replace cylinder block (1) and main bearing
caps (2) as assembly.
NOTE:
Cylinder block cannot be replaced as a single part, because it is
machined together with main bearing caps.
H
: Front mark
I
: Management code
A
: Piston grade number
B
: Front mark
C
: Piston pin grade number
D
: Identification code
JPBIA2199ZZ
Grade
0
1
Connecting rod bushing inner diameter *
22.000 - 22.006
(0.8661 - 0.8664)
22.006 - 22.012
(0.8664 - 0.8666)
Piston pin hole 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)
Limit
: Refer to
JPBIA0224ZZ
Standard
: Refer to
.
JPBIA0225ZZ
EM-136
< UNIT DISASSEMBLY AND ASSEMBLY >
CYLINDER BLOCK
PISTON TO CYLINDER BORE CLEARANCE
Cylinder Bore inner Diameter
• Using a bore gauge, measure cylinder bore for wear, out-of-round
and taper at six different points on each cylinder. [(A) and (B) direc-
tions at (C), (D) and (E)] 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.
• Oversize piston is provided. When using oversize piston, rebore
cylinder so that the clearance of the piston to cylinder bore satis-
fies the standard.
CAUTION:
When using oversize piston, use oversize pistons for all cylin-
ders with oversize piston rings.
Piston Skirt Diameter
Measure the outer diameter of piston skirt with a micrometer (A).
Piston-to-Cylinder Bore Clearance
Calculate by piston skirt diameter and cylinder bore inner diameter
[direction (B), position (D)].
(Clearance) = (Cylinder bore inner diameter) – (Piston skirt diame-
ter).
• If the calculated value exceeds the limit, replace piston and piston pin assembly. Refer to
Reboring Cylinder Bore
1.
Cylinder bore size is determined by adding piston to cylinder bore clearance to piston skirt diameter.
f
: 10 mm (0.39 in)
g
: 60 mm (2.36 in)
h
: 120 mm (4.72 in)
Standard and limit
: Refer to
JPBIA0226ZZ
Oversize (O/S)
: 0.2 mm (0.008 in)
SEM843E
Measure point
: Refer to
.
Standard
JPBIA0227ZZ
A
: Direction A
C
: Position C
E
: Position E
f
: 10 mm (0.39 in)
g
: 60 mm (2.36 in)
h
: 120 mm (4.72 in)
Standard and limit
: Refer to
.
JPBIA0226ZZ
CYLINDER BLOCK
EM-137
< UNIT DISASSEMBLY AND ASSEMBLY >
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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.
NOTE:
• 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 the specified piston to cylinder bore clearance.
5.
Measure finished cylinder bore for the out-of-round and taper.
NOTE:
Measurement should be done after cylinder bore cools down.
CRANKSHAFT MAIN JOURNAL DIAMETER
• Measure the outer diameter of crankshaft main journals with a micrometer.
• If out of the standard, measure the main bearing oil clearance. Then use undersize bearing. Refer to
CRANKSHAFT PIN JOURNAL DIAMETER
• Measure the outer diameter of crankshaft pin journal with a
micrometer (A).
• If out of the standard, measure the connecting rod bearing oil
clearance. Then use undersize bearing. Refer to
.
CRANKSHAFT OUT-OF-ROUND AND TAPER
• Measure the dimensions at four different points as shown in the
figure on each main journal and pin journal with a micrometer.
• Out-of-round is indicated by the difference in the dimensions
between (d) and (c) at (a) and (b).
• Taper is indicated by the difference in the dimensions between.
• If the measured value exceeds the limit, correct or replace crank-
shaft.
• If corrected, measure the bearing oil clearance of the corrected
main journal and/or pin journal. Then select the main bearing and/
or connecting rod bearing. Refer to
and/
EM-142, "Connecting Rod Bearing"
.
CRANKSHAFT RUNOUT
• Place V-block on precise flat table, and support the journals on the both end of crankshaft.
Rebored size calculation: D = A + B – C
where,
A: Piston skirt diameter as measured
B: Piston to cylinder bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
D: Bored diameter
Standard
: Refer to
.
Standard
: Refer to
JPBIA0228ZZ
Limit
: Refer to
.
JPBIA0229ZZ
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