On Friday, June 19, 2015 at 12:19:59 AM UTC-4, wrote:
Just wanted to get back to the group about this AC motor that was running in reverse after being disassembled and then put back together. It turns out that reversing the brushes did indeed reverse the direction of the motor.. We can't argue with success, but I still don't fully understand why this is so. Can anyone please explain this to me? Thanks, Lenny

There was a term commonly used years ago which I haven't heard for a long time. Many commutators would fail because they "threw solder". The point on the commutator that was soldered to the individual rotor winding had heated, melted the solder, and "threw" it out of the connection, leaving that winding either open or intermittent at best. The connections on this commutator, (and in fact others I've worked on over the past few years) are (and have been) clean and look like they were crimped. Is soldering to commutator segments no longer done? Lenny