Yamaha 1998 FZS600 5DM1-AE1, Service Manual

Page: 132 / 364

4-20
VALVES AND VALVE SPRINGS
ENG
a
4. Check:
valve face
Pitting/ wear
Grind the valve face.
valve stem end
Mushroom shape of diameter larger than
the body of the valve stem
Replace the
valve.
5. Measure:
valve margin thickness
a
Out of specification Replace the valve.
Valve margin thickness
0.5 mm
6. Measure:
valve stem runout
a
Out of specification Replace the valve.
When installing a new valve, always re-
place the valve guide.
If the valve is removed or replaced, always
replace the oil seal.
Valve stem runout
Limit 0.04 mm
EB403410
CHECKING THE VALVE SEATS
The following procedure applies to all of the
valves and vlve seats.
1. Eliminate:
carbon deposits
(from the valve face and valve seat)
2. Check:
valve seat
Pitting/ wear
Replace the cylinder head.
3. Measure:
valve seat width
a
Out of specification Replace the cylin-
der head.
Valve seat width
Intake: 0.9 1.1 mm
(Limit 1.6 mm)
Exhaust:0.9 1.1 mm
(Limit 1.6 mm)