Upper End Components Of Engine Inspection And Servicing - HYOSUNG RT 125 D Service Manual

3-11 ENGINE
UPPER END COMPONENTS
OF ENGINE INSPECTION
AND SERVICING
⊙ ⊙ CYLINDER HEAD DISTORTION
Decarbonize in combustion chamber.
Check the gasket surface of the cylinder head for
distortion using a straightedge and thickness gauge.
Take clearance reading at several places as
indicated.
If any clearance reading exceeds the service limit,
replace the cylinder head with a new one.
Cylinder head
Cylinder head
distortion distortion
Thickness gauge : 09900-20806
⊙ ⊙ VALVE FACE WEAR
Visually inspect each valve face for wear or damage.
If any abnormal wear is found, replace the respective
valve with a new one. The thickness of the valve face
decreases as the face wears. Measure the valve
head thickness . If the valve head thickness is not
within the specified value, replace the valve with a
new one.
Valve head thickness Cylinder head
distortion
(IN. & EX.)
Vernier calipers : 09900-20101
⊙ ⊙ VALVE STEM RUNOUT
Check the valve stem for abnormal wear or bend.
Support the valve using a V-blocks and measure the
valve stem runout using the dial gauge, as shown.
If the service limit is exceeded or abnormal condition
exists, replace the valve with a new one.
Cylinder head
Valve stem runout
(IN. & EX.) distortion
Dial gauge : 09900-20606
Magnetic stand : 09900-20701
V-block : 09900-21304
Service limit
0.05 mm (0.002 in)
Service limit
0.5 mm (0.02 in)
Service limit
0.05 mm (0.002 in)
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