Hitachi DV18DSDL Drill Driver attempted fix – fail

Having watched multiple youtube videos of people successfully repairing old and broken power tools, I decided to give it a go myself.

Because I wanted an 18V drill driver for myself I went to ebay and picked up a faulty Hitachi DV-18DSDL for £20.

An initial inspection found no brushes were fitted. Could it be a simple case of fitting new brushed and having a working drill?

Missing brushes

Sadly no. Trying to fit new brushes into the old brush house resulted in a broken brush. So the next option was to order a new brush housing, which came with brushes and brush covers too.

Replacement brush holder

Soldering on the new brush holder wasn’t a problem, but I did notice the red/black wires were on the opposite sides on the new one.

I ignored the colours and kept the brushes on the original side of the switch connector. Had I swapped them over, the forward switch would have ran the drill in reverse and vice versa.

With a new brush holder and brushes, the drill still refused to work, so I turned to youtube and looked at how to fault find the armature.

Using a multi meter and bit knowledge, I found the armature had two broken circuits. This happens when the copper wires have snapped.

Hitachi Broken Armature

Buying a replacement costs around £40, which isn’t economical, so the drill will have to be put to one side and perhaps used for spares, or split up and sold on as parts.

Another option is remove the copper windings and rewind it. I plan to do this when I come across an old motor with the correct sized wire.

Lessons learnt.

Check the armature first, before paying out for any other replacement faulty parts.