Valve Seat Inspection/Refacing - Honda 1988 Z50R Service Manual

VALVE SEAT INSPECTION/REFACING
Clean the intake and exhaust valves thoroughly to remove car -
bon deposits.
Apply a light coat ing of Prusian Blue to each valve seal. lap each
valve and seat using a hand -lapping tool.
Remove and inspect each valve.
NOTE
The valves cannot be ground. If a valve face is burned or
bad-
ly worn
Of
if
it
contacts the seat unevenlY, replace the valve.
Measure the valve seat wid t h.
SERVICE LIM IT : 2 .0
mm
(0 .08
in )
If the seal is t oo wide, too narrow, or has low spots, it must be
refinished for good sealing .
VALVE SEAT REFAC ING
NOTE
Follow the instructions are supplied with the valve seal refacing
equipment.
Use the 45 degree cutter to remove any roughness or irregulari ·
ties from the seat.
NOTE
Refaee the seal with the 45 degree cutter when the valve gUide
is replaced.
TOOLS:
Valve seat cutter
Seat cutter 24 mm (45 0 IN, EX)
Seat cutter 19 mm (32 0 EX)
Seat cutter 21.5 mm (32 0 INI
Seat cutter 22 mm (60 0 IN.EX)
Cutter holder 5 mm
U.S.A:
equivalents commercially available
07780-0010600
07780-00 12700
07780-0 0 12800
07780-0014202
07781 -00 10400
CYLINDER HEADN ALVES
" VALV E SEAT
" W IDTH
"
I
\ c - -
----7/~
32 '
""_---L._ ~ ---''___
rl '--==-=/_V\ ---' 6 _0 '
6-11