Murray 405000x8C, Instruction Book

Page: 22 / 52

MAINTENANCE
22
F-040735L
HOW TO ADJUST THE BLADE ROTATION CONTROL
WARNING: To prevent an injury, the blade rotation
control must operate correctly.
In normal usage, the blade rotation control will not require an
adjustment. However, if the cutting performance decreases or the
quality of cut is poor, make the following changes.
1. When you mow, make sure the throttle control in in the FAST
position.
2. Move the blade rotation control to the DISENGAGE position
(Figure 12).
3. Stop the engine. Disconnect the wire from the spark plug.
Blade Rotation Control
Engage Position
Disengage
Position
Figure 12
4. Check the blade(s). Keep a sharp edge on the blade(s). A blade
that is not sharp will cause the tips of the grass to become
brown.
5. Disconnect the blade drive spring from the blade control
rod. Move the blade drive spring to the middle hole
(Figure 13). This will increase the tension on the mower drive
belt.
Figure 13
Blade
Control Rod
Blade Drive Spring
Top Hole (New Belt)
Middle Hole
Bottom Hole
DISENGAGE POSITION
6. Attach the wire to the spark plug. Mow for a short distance and
again check the quality of cut. If necessary, move the blade
drive spring to the bottom hole.
7. Again check the quality of cut. If the quality of cut has not im-
proved, replace the mower drive belt. See “How To Replace
The Mower Drive Belt”. If replacing the belt does not correct the
problem, take the unit to an authorized service center.
8. Move the blade rotation control to the DISENGAGE posi-
tion. Stop the engine. Disconnect the wire from the spark plug.
Check the operation of the blade brake. Rotate the pulleys with
your hand. Make sure the brake pads are pressed tightly
against the pulleys (Figure 14).
WARNING: If the brake pads do not press tightly
against the pulleys, take the unit to an authorized
service center.
Blade Brake
Brake Pad
Against Pulley
Figure 14
9. Move the blade rotation control to the ENGAGE position.
Check the pads for the blade brake. If the pads are excessively
worn or damaged, replace the brake pad assemblies. Correct
replacement parts and assistance are available from an autho-
rized service center.
10. Attach the wire to the spark plug. Mow for a short distance and
again check the operation of the blade rotation control.
11. When you move the blade rotation control to the
DISENGAGE position, all movement will stop within five se-
conds. If there is movement of the belt or the blades continue
to rotate, engage and disengage the blade rotation control
five times to remove any excess rubber from a new mower
drive belt. If you need assistance, take the unit to an autho-
rized service center.
12. If you replace the mower drive belt, move the blade drive
spring to the top hole (Figure 13).