Toro 22157, Operator'S Manual, Page: 20 / 28

20
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
Grasp the end of the blade using a rag or a thickly padded
glove. Remove the blade nuts, the anti-scalp cup, the
accelerator, and the blade (Fig. 21).
Sharpening the Blade
File the top side of the blade to maintain its original cutting
angle (Fig. 23A) and inner cutting edge radius (Fig. 23B).
The blade will remain balanced if you remove the same
amount of material from both cutting edges.
153
1
m-4783
2
A B
Figure 23
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. 24).
1007
Figure 24
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 accelerator, the
anti-scalp cup, and the blade nuts. The sail of the blade
must point toward the top of the lawn mower housing
for proper installation. Torque the blade nuts to 15 to
27 ft-lb (20 to 37 N
m).
Operating the lawn mower without the accelerator
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
accelerator.
Warning
2. Return the lawn mower to its upright position.
3. Connect the wire to the spark plug.
Cleaning the Blade Brake
Clutch Shield
Clean the BBC (blade brake clutch) shield at the end of
each mowing season to ensure the best performance and to
prevent parts from degrading. Clean the BBC shield when
you sharpen the blade because you need to remove the
blade in order to remove the BBC shield.
1. Stop the engine and wait for all moving parts to stop.
2. Disconnect the wire from the spark plug (Fig. 9).
3. Drain the gasoline from the fuel tank; refer to steps 1
through 4 of Emptying the Fuel Tank on page 24.
4. Tip the lawn mower on its left side.
Tipping the lawn mower may cause the fuel to leak
from the carburetor or the fuel tank. Gasoline is
extremely flammable, highly explosive, and, under
certain conditions, can cause personal injury or
property damage.
Avoid fuel spills by emptying the fuel tank as
directed; never siphon.
Warning
5. Remove two blade nuts, the anti-scalp cup, the
accelerator, and the blade (Fig. 21).