KYMCO Mongoose 50-2T, Руководство по обслуживанию

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7. CYLINDER HEAD/VALVES
(90cc/70cc/50cc-4T)
7-11
CYLINDER HEAD DISASSEMBLY
Remove the valve spring cotters, retainers,
springs, spring seats, oil seals and valves
using a valve spring compressor.
Special tool
Valve Spring Compressor A120E00040
VALVE/VALVE GUIDE INSPECTION
Inspect each valve for bending, burning,
scratches or abnormal stem wear.
If any defects are found, replace the valve
with a new one.
Check valve movement in the guide.
Measure each valve stem O.D.
Measure each valve guide I.D.
Subtract each valve stem O.D. from the
corresponding guide I.D. to obtain the stem-
to-guide clearance.
Service limits : IN : 0.06 mm (0.0024 in)
EX: 0.08 mm (0.0032 in)
CYLINDER HEAD INPECTION
Check the spark plug hole and valve areas
for cracks.
Check the cylinder head for warpage with a
straight edge and feeler gauge.
Service Limit : 0.05 mm (0.002 in)
Valve Cotter Retainer Springs Springs Seat
Oil Seal
Valve
Spring Compressor
If the stem-to-guide clearance exceeds
the service limits, replace the cylinder
head as necessary.
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•
Be sure to compress the valve springs
with a valve spring compressor.
•
50cc-4T equips with a spring only for
each valve.
•
Mark all disassembled parts to ensure
correct reassembly.
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