Cub Cadet Z-Force S Series - Manual (Page 147)

Decks and Lift Shaft
141
PTO belt
Some cutting deck designs use a single belt to transfer power from the engine crankshaft directly to the blade
spindles.
Other cutting deck designs use one belt to transfer power from the engine crankshaft to a second belt that drives
the blade spindles.
On decks with two belts, the belt that goes around the crankshaft or PTO clutch is referred to in this text as the
PTO belt. The second belt is called a deck belt.
The function of the PTO belt is to transfer the mechanical force from the engine to the blades. The belt faces a lot
of different forces.
• Internal friction from the bending forces.
• The friction between the belt and the pulleys creates heat. The compression of the belt as it bends around the
pulleys also creates heat. All of this heat softens the belt which weakens it.
• Every time the electric PTO is engaged, the PTO belt is subjected to a tensile impact load. When the electric
PTO is engaged, it goes from 0 to 3,600 RPM instantly. This can actually remove sections of the belt.
NOTE: Engaging the Electric PTO before the mowing deck is placed into the grass will reduce the impact load
on the belt.
• When a blade hits an object like a rock or a tree root, the belt is subjected to an impact load similar to, but
greater than the impact load of engaging the electric PTO.
• The belt has rubber in it. as the rubber ages, it becomes brittle making it weaker.
NOTE: A damaged belt can cause the deck to vibrate when the deck is engaged. The vibration can be bad
enough to simulate an engine issue.
NOTE: Not all belt damage is visible. Broken cords inside the belt are not visible to the naked eye, but can
cause vibration issues and greatly reduce the life of the belt.
To replace the PTO belt (60” deck):
1. Remove the deck as describe at the beginning of this
chapter.
NOTE: Removal of the deck is not necessary, but makes it
easier to route the belt around the spindles.
2. Loosen the belt keepers enough to allow the belt to
slip past them.
3. Slide the belt off of the pulleys.
4. Route the new belt around the pulleys.
5. Tighten the belt keepers.
6. Install the deck as describe at the beginning of this
chapter.
7. Test run the mower before returning to service.
! CAUTION ! CAUTION
Cub Cadet belts are design to fit our equipment and are not standard lengths. Use of a non-
OEM belt may prevent the mowing deck from working properly.
Figure 8.6
PTO belt