Sym PA12B Service Manual page 107

7. Cylinder Head / Valve
Valve Guide Replacement
Heat the cylinder head with heated plate or
toaster till the temperature reaches 100~150
℃.
Caution
Do not use flame to heat the cylinder
head directly. Otherwise, the cylinder
head will be deformed.
Wear on a pair of heat-isolation glove to
protect your hands when operating.
Hold the cylinder head, and then press out old
valve guide from combustion chamber side.
Tool: Valve guide driver: 5.0 mm
Caution
Check if new valve guide is deformed
when pressed it in.
When pressing in the new valve guide,
cylinder head still have to maintain
100~150 .
℃
Adjust the valve guide driver and let valve
guide height be 13 mm.
Press in new valve guide from rocker arm
side.
Tool: Valve guide driver: 5.0 mm
Wait until cylinder head is cooled down to
room temperature, and then fix the new valve
guide with reamer.
Caution
Use cutting oil when correcting valve
guide with a reamer.
Turn the reamer in same direction when
it be inserted or rotated.
Correct the valve seat, and clean up all metal
residues from cylinder head.
Special tool：Valve Guide Reamer 5.0mm
7-10
To this chapter contents
13 mm
(0.15in)
Valve Guide Reamer 5.0mm
Valve Guide driver
Valve Guide driver
5.0mm