Can I save this elecric motor?

[Dmitry]

I'm trying to repurpose an electric motor with a drive that belongs to HD brand Husky cement mixer. It was sitting outside for a while. Now, when I turn it on, it hums and shuts off after a while. It done it before and to start it I had to push the drum manually. Now it's stuck and I can't turn the shaft at all.
Is there something I can try?.

 

[duramaxman05]

Best to disconnect the motor from the gearbox and try it. It could be that the gearbox is seized up

 

[peakbagger]

There are not a lot of parts to an electric induction motor except for how they deal with the compromise that is inherent in single phase motors which is getting it to start moving and turning in the correct direction. Other than that, its a rotor suspended in a case supported by two bearings. If the bearings are not greased, they can seize up. Definitely disconnect the motor from the gearbox and see if it spins by hand. The bearings are usually replaceable if seized. The tricky part is the method used to start the motor can vary. There usually is a centrifugal switch assembly that applies power to a start winding or a capacitor involved. On cheap motors when the end bell is removed to get at the bearings, all sorts of little pieces and parts go flying across the room. Sometimes getting everything lined up when being put back together is a PITA as the assembly is not easy.

A friend of mine got a year old large industrial compressor that was deemed unrepairable by the owner that had sent the motor out to a "electric shop". The shop told him it was unrepairable. He was curious and knows motors so he took it apart and found one of the run capacitors was bad. It cost him about $5 on the internet to get new one. He hooked it up and it runs fine. It probably a $2000 compressor.

 

[Corey]

Seems like everyone above is on the right track. Possibly the motor is lightly seized, a start capacitor is dead, or worst case water got in. Looks like there should be a fan under the shroud on the back end of the motor. Possibly you could get access to that and see if it will move at all.

Worst case, would probably be water in the motor, the windings are shot and it needs a complete re-wind. But in that case, you just need a hammer, chisel, pair of scissors...and a coil winding jig wouldn't hurt, but a couple of pegs spaced out on a 2x4 would probably get you by for one use.

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[Dmitry]

Ok, Another thing fixed with the Hearth.com community. I took the fan cover in the back of the motor and tried to turn the fan. It resisted but with some effort not to damage the fins I was able to turn it and it spun easier after that with little resistance.
I was surprised because I was trying to spin it on the gear end and couldn't do it. The half-inch thick key started to bend when I used the pipe trying to turn it.
So it works now, I still need to push the gear side to start it to work. What's interesting it spins in a direction of my push with the same effort in both directions. I'm wondering if it was designed this way, so you can mix the cement in any direction you want.

P.S. Now I'm going to work on turning this into a motorized hose reel. Going to post another thread.

 

[peakbagger]

Gearboxes frequently are one way, you can spin them from the input shaft at the motor but you cannot spin it from the output end.

Do look for way to get some grease into the motor bearings. The motor my spin but if the bearings are dry they may not last for long.

 

[Dmitry]

Gearboxes frequently are one way, you can spin them from the input shaft at the motor but you cannot spin it from the output end.

Do look for way to get some grease into the motor bearings. The motor my spin but if the bearings are dry they may not last for long.

Fairly new to this. What do I do? Take the cover and put the grease on a motor? Is there a special grease or any should be good.

 

[Corey]

Glad to know you got it working. The gear box may be 'on way' if not by mechanical design, then just by physics. Wild guess the motor might be 1750 rpm and the cement mixer portion may turn at 30-60, so ballpark 40:1 gear reduction...unlikely you could turn the output and make the motor spin - especially if the motor is stuck.

Not sure about your area, but here, it would be likely wasps/hornets/mud daubers would build a nest in the fan shroud and lock things up! But if you can break it free, it will work again, like you found.

Also not sure on the bearings - any chance to find a manual for that motor? It's been a great long time since I've seen a motor with actual serviceable bearings...and I think that might have been at an antique machinery show. Seems most motors of the past 40+ years have sealed / lifetime lubed bearings. That looks to be a "TEFC" motor...totally enclosed fan cooled - likely to deal with the dusty cement-mixer operating conditions, so might not have much in the possibility of maintenance access.