MAINTENANCE

HOW TO ADJUST THE BLADE ROTATION CONTROL

WARNING: To prevent an injury, the blade rotation control must operate correctly.

1.Stop the engine. Disconnect the wire from the spark plug.

2.Before you adjust the blade rotation control, check and level the mower housing. See “How To Level The Mower Housing.” Make sure the mower housing is level before go to the next step.

3.Set the height of the mower housing in the lowest position.

4.Move the blade rotation control to the ENGAGE position (Figure 14). Check the plastic indicator inside the blade drive spring (Figure 15). The end of the plastic indicator must be aligned ( + or - 1/8 inch / 3 mm) with the last coil of the blade drive spring.

5.If the plastic indicator is more than 1/8 inch (3 mm) from the last spring coil, an adjustment is needed. Move the blade rota- tion control to the DISENGAGE position. Disconnect the blade control rod from the pivot bracket. Turn the adjustable nut clockwise to increase the length of the coils. Turn the ad- justable nut counterclockwise to decrease the length of the coils.

6.Connect the blade control rod to the pivot bracket. Move the blade rotation control to the ENGAGE position. Check the adjustment of the blade drive spring.

7.Move the blade rotation control to the DISENGAGE posi- tion. Check the operation of the blade brake. Rotate the pulley with your hand. Make sure the pads for the blade brake are pressed tightly against the pulleys.

IMPORTANT: If the brake pads do not press tightly against the pulleys, replace the mower drive belt and repeat steps 1-7. Then, complete the remaining steps. Correct replacement parts and assistance are available from an authorized service center.

8.Move the blade rotation control to the ENGAGE position. Check the pads for the blade brake. If the pads are excessively

Blade Rotation Control

Engage Position

Throttle

Control

Disengage

Position

Figure 14

worn or damaged, replace the brake pad assemblies. Correct replacement parts and assistance are available from an autho- rized service center.

9.Attach the wire to the spark plug. Mow for a short distance and again check the operation of the blade rotation control.

10.When you move the blade rotation control to the DISENGAGE position, all movement will stop within five sec- onds if the adjustment is correct. 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 there is still blade rotation from the DISENGAGED position, adjust the blade drive spring until more of the plastic indicator extends beyond the end of the last coil. This adjustment will decrease the spring tension. If you need assistance, take the unit to an authorized service center.

11.After you operate with a new mower drive belt for several hours, check the tension of the blade drive spring.

12.If you replace the mower drive belt, adjust the blade rotation control.

-1/8” Blade Control Rod

+1/8” (3mm)Brake Pad Against Pulley (3mm)

Plastic Indicator

Pivot Bracket

Adjustable

 

 

Nut

Blade Drive Spring

 

 

Blade Brake

(Brake Pad Against Pulley)

Mower Drive Belt

Figure 15

F-040733L

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Murray 387004x48A manual HOW to Adjust the Blade Rotation Control