23
Check cylinder head
Check crack on valve seat and hole of
spark plug.
Check distorsion on cylinder head, and inspect
Flatness of cylinder head by feeler gauge or
Knife straight gauge
Limit of maintenance: 0.05
Check valve spring
Measure height of inner and outer spring
under free condition.
Limit of maintenance: (Air intake and exhaust)
Standard Limit
Inner spring
：
36.2 34.5
Outer spring
：
41.1 39.4
Replace guiding tube
Fix cylinder head, and remove guiding tube from
valve hole outwards by puller.
Caution: No damage to cylinder head is allowed
when disassembling guiding tube of valve.
Press and install new guiding tube and o-ring
on cylinder head, and make expansion for new
guiding tube.
Caution: Spread cutting oil on reamer A when
hole expansion is conducting. Turning is needed
when install or remove reamer.
Finally, wash cylinder head by cleanser, and
clean up metal chill from cutting by compressed
air.