The switch both turns your tool on and off and allows you to vary the speed of the motor. After years of use, the switch can fail; either no longer turning the tool on, or losing its ability to vary the speed of the motor.
Let's get started.
REMOVING THE SWITCH 1. Remove the top half of the handle.
a. Remove the screws securing the top half of the rear handle.
b. Lift the top half of the handle away from the unit.
2. Remove the switch.
a. Insert a long pin into the (trap-door) slot beside the blue motor wire to release the connector.
b. Remove the blue motor wire from the switch.
c. Insert a long pin into the (trap-door) slot beside the white motor wire to release the connector.
d. Remove the white motor wire from the switch.
e. Loosen the screw securing the white cord wire to the switch and remove the wire from the connector.
f. Loosen the screw securing the black cord wire to the switch and remove the wire from the connector.
g. Remove the rubber boot from the switch.
INSTALLING THE NEW SWITCH
3. Install the switch.
a. Install the rubber boot onto the new switch.
b. Install the white and black cord wires onto the new switch.
c. Secure the white and black cord wires to the switch with the screws.
d. Install the blue motor wire into the trap-door connector on the new switch.
e. Install the white motor wire into the trap-door connector on the new switch.
f. Install the switch assembly into the lower handle.
REASSEMBLING THE UNIT
4. Reinstall the top half of the handle.
a. Tuck all exposed wires into the lower handle.
b. Install the top half of the handle.
c. Secure the top half of the handle with the screws.