Service Manual

3. Check valve seat for proper contact with valve. If it is
not concentric, recondition valve seat. Check valve mar-
gin. Replace if margin is at limit.
Contact with valve seat
(to be at center of valve face)
Margin
Figure 173
4. Measure free height of spring and replace if it is not
within limit specification.
5. Check valve spring for squareness and replace if limit
is exceeded.
Free length
2
Figure 174
6. Measure clearance between valve guide and valve
stem. If clearance exceeds limit, replace valve guide,
valve or both.
Guide I.D.
Stem O.D.
Figure 175
Valve Seat Reconditioning
1. Use a valve seat cutter and pilot or seat grinder to cor-
rect seat width and seat angle.
2. After correction, use lapping compound and lap valve
and valve seat.
65
45
45
65
30
30
0.9 1.3 mm
(.035 .051 in.)
0.9 1.3 mm
(.035 .051 in.)
Figure 176
Liquid Cooled Gas Engine
Page 3
88
Workman 3000/4000 Series