Unlike modern electric drills that have polymer casings and sealed bearings, older electric drills have metallic casings and unsealed bearings. In case you’ve got an older electric drill like a Craftsman, Black and Decker or Rockwell, keeping the bearings oiled ensures that the tool will perform as it needs to. A do-it-yourselfer with basic mechanical aptitude can oil the bearings on those drills in a relatively short time.
Unplug the power cord to the drill. Put some shop rags or a towel on a worktable to reduce dust from getting in the drill.
Loosen and remove the brush caps at every side of the drill body, using a flathead screwdriver. Eliminate both brushes from the brush tubes by hand.
Open the jaws of the drill chuck, using the chuck wrench. Insert the tip of the screwdriver within the chuck. Loosen and remove the machine screw that secures the base of the toss to the outer end of the spindle shaft, and remove the toss.
Loosen and remove the machine screws that secure the front cover of this drill to the body of this drill, employing the proper screwdriver or nut driver. Pull off the cover.
Grip the end of the spindle shaft with one hand. Stabilize the drill and pull the shaft, bearing and armature assembly out of the body of the drill.
Remove the front and back bearings in the armature assembly and place them in a parts cleaning bathtub or metal pie plate.
Wear work gloves and safety glasses. Pour some acetone on the bearings and thoroughly clean the sides of every bearing, using a utility brush. Dry off the bearings with a shop rag or the towel.
Apply a generous amount of lightweight machine oil to the sides of the bearings. Fit the back and front bearings on the back and front of the armature shaft by hand. Reassemble the drill, employing the take-down procedure in reverse.