Westerbeke 6.5KW - Page 45

1. Reface the valve with a valve grinder to the specified angle.
Valve face angle: 45·
2. Reface the valve seat with a valve seat cutter while checking the
contact between the valve and valve seat.
NOTE: Reface the valve seat taking care that the valve seat con-
tacts the center position of the valve.
Intake Exhaust
Valve seat angle:
Valve seat width:
,
I~ON ... TACT POSITION
CONTACT WIDTH
1.4 mm,/
~~~··~··-~~~~_a.~.~~~n~~~~_~~~~~ .. ~ ..
1.4 mm (0.055 in) 1.4 mm (0.055 in)
90°----...
EX
IN
3. Reface the valve and valve seat with a good valve lapping
compound.
4. Measure the dimension nLn.
5. Adjust the dimension nL
n
to the standard by adding some washers
between the lower spring seat and cylinder head.
Checking Rocker Arm and Shaft
1. Check each component part of the rocker arm assembly for damage or
cracks. If necessary, replace with a new one.
2. Check to see that the oil passages of the rocker arm and shaft are
open. If any clogs are found, remove them or replace.
3. Check the clearance between the rocker arm bore and shaft. If it
exceeds the limit, replace the rocker arm bushing and shaft.
Clearance between rocker arm and shaft:
Standard:
Limit:
0.020 - 0.074 mm (0.0008 - 0.0029 in)
0.10 mm (0.0039 in)
39