Shibaura SG280E, Workshop Manual

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6) Inspect and check the valve spring.
Visually examine the valve spring for damage.
Measure the squareness of the spring. Replace the
spring if the measurement exceeds the usage limit.
Inspect the free length and spring force. Replace
the spring if the measurement exceeds the usage
limit.
Assembly
standard
Usage limit
Squareness
(mm)
1.2 2.0 or more
Free length
(mm)
35 33.5 or less
Spring force (N)
(when
compressed to
30.4mm)
79.38 68.60
2. Rocker arm
1) Measure the external diameter of the rocker arm
shaft. Replace the shaft if the measurement exceeds
the usage limit.
Rocker arm shaft wear (
φ
)
Assembly standard Usage limit
14.95 to 14.97 14.87 or less
2) Measure the internal diameter of the rocker arm.
Replace the shaft if the measurement exceeds the
usage limit.
Clearance between rocker arm and rocker arm shaft
(mm)
Assembly standard Usage limit
0.032 to 0.068 0.2 or more
3) Inspect the contact surface of the valve stem on the
rocker arm for wear and striations. If the damage is
minor, use an oil stone or grinder to repair the
surface.
Fig.2-5-10
Fig.2-5-11
Fig.2-5-12
Fig.2-5-13
Squareness
Free length