SELVA MARINE Kingfish 25, Service Manual

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7-41
POWR
Power unit
4. Measure the valve stem runout. Replace
if above specification.
Checking the valve guide
Before checking a valve guide, make sure to
check the valve.
1.
Measure the valve guide inside diameter
a
. Replace if out of specification.
2. Calculate the valve-stem-to-valve-guide
clearance as follows. Replace the valve
guide if out of specification.
Replacing the valve guide
After replacing the valve guide, check the
valve seat contact area.
1.
Remove the valve seal.
2. Remove the valve guide
1
from the
combustion chamber side using the spe-
cial service tool
2
.
3. Install a new valve guide 3 from the
camshaft side to the specified position
a
using the special service tool 2 .
Valve stem diameter
b
:
Intake:
5.475–5.490 mm (0.2156–0.2161 in)
Exhaust:
5.460–5.475 mm (0.2150–0.2156 in)
Valve stem runout:
Intake and exhaust:
0.010 mm (0.0004 in)
b
a
Valve guide inside diameter
a
:
Intake and exhaust:
5.500–5.512 mm (0.2165–0.2170 in)
Valve-stem-to-valve-guide clearance
= valve guide inside diameter –
valve stem diameter:
Intake:
0.010–0.037 mm (0.0004–0.0015 in)
Exhaust:
0.025–0.052 mm (0.0010–0.0020 in)
Valve guide remover/installer 2 :
90890-06801
1 2