Cub Cadet Z-Force S Series - Manual (Page 103)

Electrical System
97
Once the starter motor spins, we still need spark and fuel
to make the engine run. Looking at the circuits that do that:
1. The ignition sparks are generated by a magneto.
The magneto will work as long as the primary wind-
ings are not grounded. With the key switch in any
position other than off, there is no connection
between the M (Magneto) terminal and the G
(Ground) terminal. See Figure 7.13.
2. There is an afterfire solenoid on the carburetor.
When it is energized, fuel flows normally through the
carburetor. When it is not energized, it closes off the
fuel flow through the main jet of the carburetor. The
purpose of the solenoid is to prevent unburned fuel
from being pumped through the engine after the igni-
tion is turned off. This unburned fuel accumulates in
the muffler and may ignite with an alarming noise.
See Figure 7.14.
Figure 7.13
Magneto
Magneto
Primary winding
ground wire
Figure 7.14
Afterfire sol.