Yamaha Rhino 450 YXR45FAV, Service Manual

Page: 153 / 413

4 - 22
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>: 0.08 mm (0.0031 in)
Exhaust
0.030 ~ 0.057 mm
(0.0012 ~ 0.0022 in)
<Limit>: 0.10 mm (0.0039 in)
2. Replace:
• valve guide
▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼
NOTE:
To ease guide removal, installation and to
maintain correct fit, heat the cylinder head to
100 °C (212 °F) in an oven.
a. Remove the valve guide using a valve guide
remover 1 .
b. Install the new valve guide using a valve
guide remover 1 and valve guide installer
2 .
c. After installing the valve guide, bore the
valve guide using a valve guide reamer 3
to obtain proper stem-to-guide clearance.
NOTE:
After replacing the valve guide reface the valve
seat.
▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲▲▲
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