Kimble Motor Trouble

Is the brush rigging shifting while it’s in operation? Variable speed brush shifting motors will reverse when the brushes move across the “neutral point” of the commutator, often accompanied by some extra sparking.

motor sounds nasty. need to get a knowlegable person in there to diagnose. bearings, amperage, voltage drop, all need to be determined. We have a very good motor repair company here in Milwaukee, Wis. if that is an option.

Second that (and I should have mentioned it myself). Those motors can run forever but still need some maintenance; that’s probably 70-80 years old and looks like it’s had a rough life, some professional attention will give it another few decades of service.

Most larger cities have motor shops, and don’t let the shop just try to sell you a replacement (some will).

Mmmm I suppose I shouldn’t be surprised haha. I don’t imagine the brush is shifting while in operation at least from what I see, but I know little about motors.

Ericm, thanks for the offer but I’m in Texas. I’ll look around for some local shops. Thanks everyone for your suggestions!

Y’all. I actually think the issue was just those loose screws meant to keep the brushes from moving! You were spot on zbang.

The position of the brushes determines both the speed and direction of the motor; highest speed is at the ends of travel, slow-to-reverse in the middle. Some motors have a lever to shift them, I’m not sure about that specific one. (And so far, I haven’t found a spec or instruction sheet for them. Still looking.)