How to repair vacuum cleaner electric motors brushes that spit fire (sparks)?
I wish I had a nickel for every time someone has brought some item in for repair that is operated by an electric motor and was told that the problem was that it needed new brushes. That’s true in maybe 1 % of the cases. The rest of the time, especially if there are a lot of sparks and the spark trail seems to follow the commutator segments around as the armature spins, the armature will have a few segments that have a black burned spot inbetween them. That’s a shorted commutator and that makes the armature so much scrap metal. It will need a new armature and brushes or just a new motor.
