How to Repair a Portable Drill

Remove all the screws holding the exterior of the portable drill together. Lay out a towel and place removed screws on top to prevent the screws from rolling away. Once finished, open the casing to expose the portable drill's inner mechanical components.

Unfasten the screws located at the bottom of the drill's mechanical components. These screws hold the electrical power assembly in position. Once you remove the screws, pull the mechanical components from the drill's exterior casing. The components come out in one piece. Use gentle force when pulling the components out to prevent damage to any of the parts.

Inspect the trigger component, located beneath the drill motor. This piece of your portable drill is likely to experience malfunction since it gets significant use. Remove and replace it if you see any damage to the trigger assembly.

Inspect the plastic wheel fans for damage. These large, circular fans crack and sometimes break into pieces after repeated use. Slide these pieces from the portable drill assembly and replace.

Reassemble the portable drill again after inspecting the interior components. Place all pieces back in their original positions and close the exterior casing by refastening the removed screws. Turn on the portable drill to test.

Place the two prongs of a multimeter to the electrical wiring of the portable drill and record the findings. Compare the reading to the owner's manual or the back plate with ohm and voltage information. The drill likely suffers from an electrical wiring problem that requires technical assistance if the multimeter reading and the listed voltage do not coincide.