Yamaha Scorpio Service Manual page 100

VALVES AND VALVE SPRINGS
2.Attach:
Valve spring compressor 1
G
3.Remove:
Valve cotters 1
G
Upper spring seat 2
G
Outer valve spring 3
G
Inner valve spring 4
G
Oil seal 5
G
Lower spring seat 6
G
Valve 7
G
NOTE:
Identify each part position very carefully so
G
that it can be reinstalled in its original place.
Deburr any deformed valve stem end. Use
G
an oil stone to smooth the stem end.
1 Deburr
2 Valve stem
4.Eliminate:
Carbon deposit
G
From the combustion chamber.
Use a rounded scraper.
NOTE:
Do not use a sharp instrument and avoid dam-
aging or scratching:
Spark plug threads
G
Valve seat
G
Cylinder head
G
4 - 23
ENG
Valve spring compressor:
90890-04019