Shibaura SG280E, Workshop Manual

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45
C
a
te
g
o
ry
C
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s
if
i-
c
a
ti
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n
Inspection item
Standard
dimension
Assembly
standard
Required
repair
level
Usage
limit
Remarks
Journal diameter φ 68
φ 67.951
to 67.970
φ 67.40
Crank pin diameter
φ 52
φ 51.964
to 51.975
φ 51.40
Journal and pin finishing
precision
1.6Z
Crankshaft deflection 0.02 or less
0.05 or
more
Allowance in crankshaft
axis direction
0.1 to 0.4 0.5
Thickness of thrust washer 3.0 2.95 to 3.00 2.8
Bush (journal metal) internal
diameter x external diameter
φ
68x72
Clearance between
crank journal and bush (journal
metal)
0.044 to 0.102 0.2 Oil clearance
Center bearing (internal
diameter x external diameter)
φ 68x72
Clearance between
crank journal and center
bearing (#2, 3, and 4)
0.044 to 0.102 0.2 Oil clearance
P
ri
m
a
ry
m
o
v
in
g
p
a
rt
s
C
ra
n
k
s
h
a
ft
Bearing holder (upper
and lower) tightening torque
(N
⋅ m)
49 to 53.9
Intake/
exhaust
34.45 to 35.01 34.0
Cam height
Fuel
pump
42.94 to 43.06 42.81
Cam shaft deflection 0.03 or less 0.1
C
a
m
s
h
a
ft
Cam gear backlash 0.08 0.25
Stem on intake valve 6.97 6.955 to 6.970 6.89
Stem on exhaust valve 6.955 6.940 to 6.955 6.84
Intake 0.03 to 0.06
0.2 or
more
Clearance between
valve steam and
valve guide
Exhaust 0.040 to 0.065
0.25 or
more
Valve thickness
1.0 0.925 to 1.075 0.5
Valve clearance (intake and
exhaust)
0.2 0.5
When the engine
is cool
Spring force (N) (when
compressed to 30.4mm)
79.38 68.6
Free height 35 33.5
V
a
lv
e
c
o
m
p
o
n
e
n
ts
V
a
lv
e
s
V
a
lv
e
s
p
ri
n
g
Squareness
1.2 2.0