19
Inspecting the Blade
Carefully examine the blade for sharpness and wear,
especially where the flat and the curved parts meet
(Fig. 26A). Because 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 lawn mower. If you
notice a slot or wear (Figs. 26B and 26C), replace the
blade; refer to Removing the Blade on page 19.
270
1
1
1
2
3
4
A
B
C
Figure 26
1.
Sail
2.
Flat part of blade
3.
Wear
4.
Slot formed
Note: For the best performance, install a new Toro blade
before the cutting season begins. During the year, file down
any small nicks to maintain the cutting edge.
Danger
A worn or damaged blade can break, and a piece
of the blade could be thrown into the operator’s or
bystander’s area, resulting in serious personal
injury or death.
•
Inspect the blade periodically for wear or
damage.
•
Replace a worn or damaged blade.
Removing the Blade
Operating the lawn mower without the blade
stiffener in place can cause the blade to flex, bend,
or break, resulting in serious injury or death to the
operator or bystanders.
Do not operate the lawn mower without the blade
stiffener.
Warning
1. Grasp the end of the blade using a rag or a thickly
padded glove.
2. Remove the blade bolt, the lock washer, the blade, and
the blade stiffener (Fig. 25).
Note: Turn the blade bolt counterclockwise to loosen it.
Sharpening the Blade
File the top side of the blade to maintain its original cutting
angle (Fig. 27A) and inner cutting edge radius (Fig. 27B).
The blade will remain balanced if you remove the same
amount of material from both cutting edges.
153
1
m4783
2
A
B
Figure 27
1.
Sharpen at this angle only
2.
Maintain the original
radius here
Balancing the Blade
1. Check the balance of the blade by placing the center
hole of the blade over a nail or screwdriver shank
clamped horizontally in a vise (Fig. 28).
1007
Figure 28
Note: You can also check the balance using a commercially
manufactured, blade balancer.
2. If either end of the blade rotates downward, file that end
(not the cutting edge or the end near the cutting edge).
The blade is properly balanced when neither end drops.
Installing the Blade
1. Install a sharp, balanced Toro blade, the blade stiffener,
the lock washer, and the blade bolt.
Note: The sail part of the blade must point upward
(toward the top of the lawn mower housing).
2. Torque the blade bolt to 45 to 60 ft-lb (33 to 44 N
m).
3. Turn the lawn mower upright.
4. Connect the wire to the spark plug.
Summary of Contents for 20833
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