Cub Cadet MTD P71 Series - Manual (Page 91)

Cylinder head
85
5. Inspect the valve seat. See Figure 9.9.
• Valve seats are 46 degrees.
NOTE: This engine does not have the standard 3 angle
cut.
• Seat width should be 0.044” - 0.054” (1.13 - 1.38
mm).
NOTE: The valve seat can be ground to clean it up as long
as the finished seat is within the tolerances listed
above.
6. Inspect the valve stem. See Figure 9.10.
7. Inspect the valve springs.
NOTE: Valve spring free length should be 1.302” - 1.362”
(33.07 - 34.59 mm).
8. Install the valves in the cylinder head by following
steps 2 - 5 in reverse order.
9. Test the valves for leaks by:
9a. Place the cylinder head on a couple of wood
blocks with the valves facing up.
9b. Pour a small amount of gasoline or parts clean-
ing solvent into the combustion chamber (just
enough to cover the valves).
9c. Let the cylinder head sit for ten minutes.
9d. Check for gasoline leaking out of the intake and
exhaust ports.
10. Install the cylinder head by following the steps
described earlier in this chapter.
11. Set the valve lash by following the steps described in
Chapter 1: Introduction.
12. Test run the engine in a safe area before returning it
to service.
Figure 9.9
Seat angle is 46
o
0.043-.050”
Figure 9.10
45
o
Inspect for a
burnt edge