Yamaha WaveRunner - Valve Spring Inspection; Valve Inspection

5-71
E
POWR
VALVES AND VALVE SPRINGS
Valve spring inspection
1. Measure:
• Valve spring free length
a
Out of specification
→
Replace the
valve spring.
2. Measure:
• Valve spring tilt
a
Out of specification
→
Replace the
valve spring.
Valve spring free length:
Intake valve spring:
38.90 mm (1.53 in)
Exhaust valve spring:
40.67 mm (1.60 in)
Valve spring tilt:
Intake valve spring:
1.7 mm (0.067 in)
Exhaust valve spring:
1.8 mm (0.071 in)
Valve inspection
1. Eliminate:
• Carbon deposits
(from the valve face and valve seat)
2. Check:
• Valve face
Pitting/wear
→
Replace the valve.
3. Measure:
• Valve margin thickness
a
Out of specification
→
Replace the
valve.
Valve margin thickness:
0.5–0.9 mm (0.0197–0.0354 in)