6. CYLINDER HEAD/VALVES                                                                   DINK50/ 125

CYLINDER HEAD DISASSEMBLY
Remove the valve spring cotters, retainers,           Valve Cotter   Retainer   Springs Springs Seat
springs, spring seats, oil seals and valves using a
valve spring compressor.
 · Be sure to compress the valve springs
       with a valve spring compressor.
     · Mark all disassembled parts to ensure
       correct reassembly.

 Special


                                                      Spring Compressor    Oil Seal   Valve

Valve Spring Compressor        E040




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 : 0.06mm replace if over
          EX: 0.08mm replace if over
 If the stem-to-guide clearance exceeds
     the service limits, replace the cylinder
     head as necessary.




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: 0.05mm repair or replace if
over
 If the stem-to-guide clearance exceeds
     the service limits, replace the cylinder
     head as necessary.

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