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Strange gearmotor problem

Went to an estate sale of an incredible packrat. Saw some really amazing crap like a lot of flat belt drive (like in old factories) mills, grinders etc. All in bad shape from years of neglect and sitting in an unheated barn.

I picked up a gearmotor, with a GE motor, 115v, weight maybe 10 lbs.

It would not start when connected to 115v. It hums and does not start spinning. However, if I give the output low speed shaft a turn with pliers, it starts spinning and keeps spinning.

The motor does not have a visible hump for a capacitor.

So, my thinking goes, either there is a cap inside the motor that is bad, or , perhaps, the motor is of the kind that does not require a capacitor and has only minimum torque at stall, and somehow there is some stuckage in the motor bearings or gears. Possibly the weather is cold and the gear lubricant is too thick.

any ideas, thanks, i

i
Reply to
Ignoramus9972
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Externally mounted capacitor. Maybe you can find a wiring diagram, if it has a nameplate. How is it wired? Terminals, and or wires? Dave

Reply to
Mechanical Magic

"Ignoramus9972" (clip) if I give the output low speed shaft a turn with

^^^^^^^^^^^^^^^^^^^ Will it start in either direction when helped with pliers? If the poor starting is caused by gummy bearings it will not run backwards. If the problem is in the capacitor (bad or missing) you will be able to start it in either direction. This could also indicate a stuck start/run switch.

Reply to
Leo Lichtman

As someone else mentioned: will it start in either direction? If so, bad switch or bad starter winding. If there are only 2 wires and no cap, suspect a stuck centrifugal starting switch. Pull off the wiring end, jab at the switch.

Ignoramus9972 wrote:

Reply to
RoyJ

THanks, gentlemen. There are three wires, red, white and green, which I assumed was the ground. Now I think that it is a cap start and re quires an external capacitor.

i [BB> As someone else mentioned: will it start in either direction? If so, bad
Reply to
Ignoramus9972

Pure induction motor. No starting cap - has a clutch within. Might have a dirty switch so the start winding doesn't kick in. Maybe the bearings are firm but the mechanical advantage is enough to power it on.

Mart> Went to an estate sale of an incredible packrat. Saw some really

Reply to
Martin H. Eastburn

I'd take off the end plate of the motor and you'll probably find a centrifugal starting switch in there.... clean it up and it'll probably be fine..... Ken.

Reply to
Ken Sterling

Yup. I acquired a few little gearmotors a few years ago that were door closers from a jail. Had an external cap that was held to the gearmotor by what looked like a big rubber band. Absolutely no mounting bracket, mounting holes, nothing but a 2" wide band that looked like something sliced from a motorcycle innertube.

Reply to
BillM

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