Yamaha WaveRunner FZR-GX1800 Service Manual page 177

POWR
Cylinder head
a
a
b
5-70
2. Measure:
• Valve face width a
Out of specification → Replace the
valve.
Valve face width a:
Intake and exhaust:
2.26–2.83 mm (0.089–0.111 in)
• Valve margin thickness b
Out of specification → Replace the
valve.
Valve margin thickness b:
Intake and exhaust:
0.80–1.20 mm (0.031–0.047 in)
3. Measure:
• Valve stem diameter a
Out of specification → Replace the
valve.
Valve stem diameter a:
Intake:
5.477–5.492 mm
(0.2156–0.2162 in)
Exhaust:
5.464–5.479 mm
(0.2151–0.2157 in)
4. Measure:
• Valve stem runout
Out of specification → Replace the
valve.
Valve stem runout limit:
Intake and exhaust:
0.01 mm (0.0004 in)
E
1
2
3
4
5
6
7
8
9