Yamaha LIT-11616-16-02 Model Vehicle User Manual


 
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ENG
CAMSHAFT, ROCKER ARMS AND VALVES
CHECKING THE VALVES AND VALVE
SPRINGS
1.Measure:
Stem-to-guide clearance
Out of specification Replace the valve
guide.
Stem-to-guide clearance =
valve guide inside diameter
a
valve stem diameter
b
Clearance (stem to guide):
Intake:
0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)
<Limit>: 0.080 mm (0.0031 in)
Exhaust:
0.030 ~ 0.057 mm
(0.0012 ~ 0.0022 in)
<Limit>: 0.100 mm (0.0039 in)
2.Replace:
Valve guide
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Replacement steps:
N
OTE:
To ease guide removal, installation and to
maintain correct fit, heat the cylinder head to
100 °C (212 °F) in an oven.
Remove the valve guide using a valve guide
remover 1.
Install the new valve guide using a valve
guide remover 1 and valve guide installer 2.
After installing the valve guide, bore the
valve guide using a valve guide reamer 3 to
obtain proper stem-to-guide clearance.
N
OTE:
After replacing the valve guide reface the valve
seat.
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Valve guide remover (7.0 mm):
P/N. YM-01225-A, 90890-01225
Valve guide installer (7.0 mm):
P/N. YM-04017, 90890-04017
Valve guide reamer (7.0 mm):
P/N. YM-01227, 90890-01227