Correcting The Cutting Unit Mismatch - Toro 31598 Operator's Manual

wears down, the quality-of-cut will degrade somewhat,
although the cutting edges are sharp. The cutting edge
of the blade must be sharp so that the grass is cut rather
than torn. A dull cutting edge is evident when the tips
of the grass appear brown and shredded. Sharpen the
cutting edges to correct this condition.
1. Position the machine on a level surface. Raise the
cutting unit, engage the parking brake, put the
traction pedal in neutral, make sure the PTO switch
is in the Off position, stop the engine, and remove
the ignition key.
2. Examine the cutting ends of the blade carefully,
especially where the flat and curved parts of the
blade meet (Figure 101). Since sand and abrasive
material can wear away the metal that connects
the flat and curved parts of the blade, check the
blade before using the mower. If wear is noticed
(Figure 101), replace the blade.
Figure 101
1. Cutting Edge
2. Curved Area
3. Examine the cutting edges of all of the blades.
Sharpen the cutting edges if they are dull or nicked.
Sharpen only the top of the cutting edge and
maintain the original cutting angle to make sure
of sharpness (Figure 102). The blade will remain
balanced if the same amount of metal is removed
from both cutting edges.
DANGER
If the blade is allowed to wear, a slot will form
between the sail and flat part of the blade
(Figure 101). Eventually a piece of the blade
may break off and be thrown from under the
housing, possibly resulting in serious injury to
you or bystanders.
• Inspect the blade periodically for wear or
damage.
• Never try to straighten a blade that is bent or
weld a broken or cracked blade.
• Replace a worn or damaged blade.
3. Wear/slot Forming
4. Crack
1. Sharpen at original angle
Note: Remove the blades and sharpen them on a
grinder. After sharpening the cutting edges, install
the blade with the anti-scalp cup and blade bolt; refer
to Removing and Installing the Cutter Blade(s).
Correcting the Cutting Unit
Mismatch
If there is mismatch between the blades, on a single
cutting unit, the grass will appear streaked when it is cut.
This problem can be corrected by making sure that the
blades are straight.
1. Using a 3 foot (1 meter) long carpenters level, find
a level surface on the shop floor.
2. Raise the height-of-cut to the highest position; refer
to Adjusting the Height-Of-Cut.
3. Lower the cutting unit onto the flat surface. Remove
the covers from the top of the cutting unit.
4. Rotate the blades until the ends face forward and
backward. Measure from the floor to the front tip
of the cutting edge. Record this dimension. Then
rotate the same blade so that the opposite end is
forward, and measure again. The difference between
the dimensions must not exceed 1/8 inch (3 mm).
If the dimension exceeds 1/8 inch (3 mm), replace
the blade because it is bent. Make sure to measure
all of the blades.
5. Check that deck is level side to side and adjust as
required.
6. Install the belt covers.
66
Figure 102