Adjusting The Idler Pulley; Replacing The Drive Belt - Toro 30551 Operator's Manual

1. Bolt
2. Locknuts
5. To remove the pivot brackets, remove the carriage
bolts and nuts (Figure 29).
6. Install the pivot brackets on top of the discharge
opening with the carriage bolts and nuts.
Note: The head of the carriage bolts must be on the
inside of the cutting unit.
7. Position the deflector mounts on the pivot brackets
and secure the parts together with the capscrews,
locknuts, and springs.
Note: Both locknuts must face each other. Tighten the
locknuts until they are flush against the deflector pivots.
8. Lift the deflector and allow it to drop to check the
spring tension.
Note: The deflector must be held firmly in the full
downward position by the spring tension. Correct it
if necessary.

Adjusting the Idler Pulley

The idler pulley applies force against the belt so that power
can be transmitted to the blade pulleys. If the idler is not
tensioned against the belt with sufficient force, maximum
power will not be transmitted to the pulleys. Tension on the
belt requires 47 to 54 N-m (35 to 40 ft-lb) of torque on the
large nut, which applies force against the belt. If the idler is
not adjusted to these specifications, adjust it.
Important: The fasteners on the covers of this machine
are designed to remain on the cover after removal.
Loosen all of the fasteners on each cover a few turns so
that the cover is loose but still attached, then go back
and loosen them until the cover comes free. This will
prevent you from accidentally stripping the bolts free
of the retainers.
1. Position the machine on a level surface.
2. Lower the cutting unit, engage the parking brake, put
the traction pedal in neutral, the PTO lever in the Off
Figure 29
3. Pivot brackets
4. Spring
position, shut the engine off, and remove the ignition
key.
3. Remove the cover from the center cutting unit.
4. Loosen the 2 nuts that secure the idler plate in place.
5. Use a socket and torque wrench to tighten the idler
adjusting nut to 47 to 54 N-m (35 to 40 ft-lb) (Figure
30).
1. Idler plate
2. Nuts (2)
6. Hold the torque against the belt and tighten the 2 nuts
so that the idler plate is held securely in place.
7. Release the idler adjusting nut.
8. Install the cover.

Replacing the Drive Belt

The blade drive belt, tensioned by the adjustable idler, is very
durable. However, after many hours of use, the belt will show
signs of wear. Signs of a worn belt are: squealing when belt
is rotating, blades slipping when cutting grass, frayed edges,
burn marks, and cracks. Replace the belt if any of these
conditions are evident.
Important: The fasteners on the covers of this machine
are designed to remain on the cover after removal.
Loosen all of the fasteners on each cover a few turns so
that the cover is loose but still attached, then go back
and loosen them until the cover comes free. This will
prevent you from accidentally stripping the bolts free
of the retainers.
1. Position the machine on a level surface.
2. Lower the cutting unit, engage the parking brake, put
the traction pedal in neutral and the PTO lever in the
Off position, shut the engine off, and remove the
ignition key.
3. Remove the covers from the top of the cutting unit.
4. Loosen the 2 nuts that secure the idler plate in place,
and remove the old belt from the pulleys.
21
Figure 30
3. Idler adjusting nut