small Magnetic motor repair (this shoudl be simple!!)

[adam.woodring]

Thanks in advance for your help . . . I have a small Magnetic drive motor that powers a pump for a ice maker. Pretty simple device, just stopped working the other day.

I removed it from the ice maker and put power to it on my bench. The motor hummed but the shaft didn't turn. I gave the shaft a slight push and it took off spinning! So it will work, just can't seem to start up on its own.

I'm handy but know NOTHING about these little magnetic drive motors. . . any ideas out there?? thanks again!

 

[(*steve*)]

I'd guess that there are several windings and one is open circuit.

That's a generic answer, it may not apply to your motor.

 

[duke37]

The smallest motors have shaded poles and these produce very little torque at rest, check that the bearings are not stiff.
Bigger motors have a capacitor to set the phase in one winding, these capacitors can fail.
Bigger yet motors have a capacitor which is switched in during the start and switched out during run. The switches can fail.
What type of motor do you have?

 

[davelectronic]

motor wont start

Hi adam.woodring.
As you can spin it up by hand and it runs might surgest a start, or start run capacitor problem, is the motor shaft free running, or tight, it might have shorted turns in the stator rotor or armature, depending on motor type, is it an induction motor, stator and rotor, or a brushed motor, shunt or series wound ? The application ice maker might mean a fair amount of torque needed, but as it runs spun by hand i would try or test the capacitor if it has one.

If its a wound armature it could be a commutator problem.
Dave.

 

[shrtrnd]

All good ideas suggested.
Here's the one I resort to when I've checked everything else:
The motor is binding because it wore-out, and needs to be replaced.
MANY times I find the armature physically scrapping the frame.
Any number of reasons why;
Shaft warped, oxidation or corrosion on the armature itself, bearings binding or worn.
Problem could be as identified above, but it could also just be mechanical binding.