Cub Cadet MTD 70 Series - Manual (Page 119)

Crankshaft, piston and connecting rod
113
Piston Inspection
1. Clean the piston and remove all carbon from the rings
and ring groves.
2. Insert one ring into the cylinder. Push it down about
one inch from the top. See Figure 10.11.
3. Measure the end gap with a feeler gauge and com-
pare to the chart at the end of this chapter. See Fig-
ure 10.11.
4. Repeat steps 3 and 4 on the other rings.
NOTE: Piston rings are not available as service parts. If
any of the end gaps are out of spec, the engine
must be short blocked.
5. Install rings back onto the piston. See Figure 10.12.
NOTE: The top ring is symmetrical and the middle ring has
a tapered profile. The larger radius of the middle
ring should face the crankshaft. See Figure 10.13.
Figure 10.11
Feeler gauge
Piston ring
Figure 10.12
Figure 10.13
Top piston ring
Middle piston
3-piece oil ring
ring