Orion AGB-21G - Checking the Valves and Valve Guides

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CAMSHAFT /VALVES AND VALVE SPRINGS
NOTE:
NOTE:
CHECKING THE VALVES AND VALVE GUIDES
The following procedure applies to all of the
valves and valve guides.
1. Measure:
valve-stem-to-valve-guide clearance
Valve-stem-to-valve-guide clearance =
Valve guide inside diameter
a
–
Valve stem diameter
b
Out of specification Replace the valve
guide.
Valve-stem-to-valve-guide clear-
ance
Intake
0.015
0.042 mm
Limit: 0.08 mm
Exhaust
0.030
0.057 mm
Limit: 0.10 mm
2. Replace:
valve guide
To ease valve guide removal and installation,
and to maintain the correct fit, heat the cylinder
head to 100
C in an oven.
a. Remove the valve guide with a valve guide
remover
1
.
b. Install the new valve guide with a valve guide
installer
2
and valve guide remover
1
.
c. After installing the valve guide, bore the
valve guide with a valve guide reamer
3
to
obtain the proper valve-stem-to-valve-guide
clearance.
After replacing the valve guide, reface the valve
seat.