Cub Cadet MTD 70 Series - Manual (Page 65)

F UEL S YSTEM AND G OVERNOR
59
Governor
The engine speed is controlled by a balance between
the force applied by a spring (pulling the throttle open) and
a flyweight mechanism within the engine applying force to
the governor arm (pushing the throttle closed).
See Figure 4.37.
NOTE: While the mechanism is simple and robust, it is
important to pay attention when working on parts
near the governor. Binding caused by interference
with mis-routed lines or cables may make the gov-
ernor unresponsive.
NOTE: When a governed engine “hunts”, it is generally an
indication of a lean fuel/air mixture, rather than a
problem with the governor.
Governor arm
To remove the governor arm from the governor shaft:
1. Remove the fuel tank by following the steps
described in the Fuel Tank section of this chapter.
2. Unhook the governor spring.
NOTE: Mark which hole the spring was in to ensure
it goes back in the same hole.
3. Unhook the governor linage and throttle return
spring.
4. Loosen the nut and through bolt. See Figure 4.38.
5. Carefully spread open the seam on the arm.
6. Carefully slide the Governor arm off of the governor
shaft.
7. Install the governor arm by rotating the governor
shaft clockwise until it stops.
8. Slide the arm onto the shaft. The flat on the top of the shaft should be roughly perpendicular to the arm.
NOTE: There is a hairpin clip that keeps the governor shaft from sliding into the engine. It may be necessary to
hold the shaft while sliding the arm on to prevent it from going into the engine.
9. Tighten the nut on the clamp bolt to secure the arm.
10. Attach the governor linkage and spring.
11. Adjust the governor to maintain top no-load speed as described in a previous section of this chapter.
Figure 4.37
Spring tension
Governor action
Figure 4.38
Loosen nut
Spread here