16.The commutator should be clean and shiny; if it is dull and black, you can clean it with a commutator cleaning stone.
Clean
Dirty
17.To clean the commutator, press the commutator cleaning stone against the commutator and rotate the armature by turning the spindle shaft by hand. Continue for a minute or until commutator is clean and shiny.
18.Reconnect the power wire, ensuring that the wire path is correct. Reinstall the carbon brush holder into the slot on motor housing and slide in until the tab for the screw hits the stop. Install the screw using light pressure to prevent it from stripping.
19.After both carbon brushes have been replaced you can reassemble the rear cover. Make sure the power wires are in the tool to prevent pinching of the wires.
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