Cylinder Head Assembly - Shibaura CM214 Workshop Manual

2) Cylinder head ass'y
Disassembly
(1) Using a valve spring replacer, compress the valve
spring to remove the valve cotter, retainer, spring and
valve.
(2) Remove the valve guide seal.
1. Valve guide seal
2. Spring
3. Retainer
Inspection and service
(1) Distortion of cylinder head bottom surface.
Apply a straight edge to the bottom surface of the
cylinder head, and insert a thickness gauge at 6 points
from A to F in the right figure and measure distortion.
If the distortion exceeds the repair value, correct with
surface grinder or the like.
Distortion at cylinder head bottom surface
Standard assembling value
Less than 0.05
(2) Valve guide and valve stem
➀ Check the head and stem of each valve and replace
if burnout, wear or deformation is remarkable.
➁ Measure the outside diameter at the position I, II,
and III on the valve stem with a micrometer and
replace if the result is less than the service limit.
Wear of valve stem
Intake valve
Standard
Service
assembling
limit
value
6.955 – 6.97 6.89
➂ Replace a valve if its head thickness is less than
service limit.
Valve head thickness
Standard assembling value
0.775 – 1.075
4. Valve
5. Valve cotter
(mm)
Repair value
More than 0.12
(mm)
Exhaust valve
Standard
Service
assembling
limit
value
6.94 – 6.955 6.84
(mm)
Service limit
Less than 0.5
16
111V
112V
113V
114V
115V