Valve And Valve Spring Inspection; Valve Removal; Valve Inspection - Westerbeke 12C-TWO Operator's Manual

VALVE AND VALVE SPRING INSPECTION
VALVE REMOVAL
1. Dismount the cylinder head assembly.
2. Depress the valve retainer (to compress the valve spring)
and remove the retainer lock.
REMOVING VALVES
3. Remove the valve.
4. Inspect all the components and repair or replace any
defective parts.
SQUARENESS CHECK ---'~
SQUARENESS GAUGE
Squareness Check
Standard
2•
Limit 3•
Valve Spring Squareness Check. Check the squareness of
the valve spring and, if it is more than the limit, replace the
spring ..
Valve Spring Fitting Pressure Check. Check the valve
spring fitting pressure with a valve spring tester and, if the
pressure is less than the limit, replace the spring.
Pressure (load) Test
Standard 13.0951bs/1.398in (5.94 kg/35.5 mm)
limit -15%
NOTE:
Measure the fitting pressure after compressing the
spring several times.
Valve Spring Free Length Check. Measure the free length
of the valve spring and if the free length is less than the limit,
replace it.
VAlVE SPRING TESTER
Free length Test
Standard 1.595 in (40.5 mm)
limit 1.5 in (39.3 mm)
Valve Inspection
Valve Stem Wear Inspection. If the valve stem is bent or its
diameter is less than the standard, replace the valve.
Valve Stem
Standard
Margin
Standard
limit
6.6 mm (0.260 in)
1.0 mm (0.039 in)
0.5 mm (0.019 in)
1. If the valve face is found .worn down. resurface it with a
valve refacer. If the margin of the resurfaced valve
exceeds the service limit, replace the valve.
2. If the valve stem end has been indented by wear. flatten it
with an oil stone.
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INSPECTING VALVES
WESTERBEKE
Engines & Generators
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