5hp leeson motor trouble

[Tim Elett]

Has vibration and gets hot after short time using on woodmaster sander, dos does not seem to get warm if running sander only, I have replaced bearing on shaft and pulley, ideas?

[Paul F Franklin]

Single or three phase?

[Tim Elett]

Single 220 checked power ok

[Myles Moran]

How is the centrifugal switch? Does it look like it's been arcing a lot and well worn?

[Richard Coers]

How does it run with the drive belts (motor only)? It's very easy to overload a motor on a drum sander. Have you ever measured current draw on the motor while sanding? Big commercial sanders have a meter on them so you don't try to remove too much wood and burn out the motor.

[Tim Elett]

Myles: do not know what that is ,sorry
Richard:seems to run fine with no load but motor seems to get to hot ,ran one little board, couldn't keep hand on motor.

[Paul F Franklin]

It is likely that your motor has two capacitors, a start cap and a run cap. The start cap is only used when the motor is starting up; when it gets near full speed a centrifugal switch inside the motor housing disconnects it . The start cap circuit provides extra torque to get the motor up to speed quickly.

If the centrifugal switch is dirty or has failed in the closed position, the motor will quickly overheat because the switch did not disconnect the start capacitor as it should have.

That is one possible cause of motor overheating.
To check the switch, the motor housing (or at least the end bell opposite the shaft) has to be removed to gain access to the switch.

However, if there are ventilation openings in the end of the motor, you can try blowing out the motor with compressed air; that may be enough to free up a switch that is jammed because of dust/dirt build up.

[Tim Elett]

Thanks, that makes sense because the motor was very dirty I will check in the morning 🌄

[Tim Elett]

It is likely that your motor has two capacitors, a start cap and a run cap. The start cap is only used when the motor is starting up; when it gets near full speed a centrifugal switch inside the motor housing disconnects it . The start cap circuit provides extra torque to get the motor up to speed quickly.

If the centrifugal switch is dirty or has failed in the closed position, the motor will quickly overheat because the switch did not disconnect the start capacitor as it should have.

That is one possible cause of motor overheating.
To check the switch, the motor housing (or at least the end bell opposite the shaft) has to be removed to gain access to the switch.

However, if there are ventilation openings in the end of the motor, you can try blowing out the motor with compressed air; that may be enough to free up a switch that is jammed because of dust/dirt build up.
I was having morning coffee and was reading the post on the Laguna bandsaw Bill posted that you can hear the switch as the motor shuts down, I do hear this,do you still recommend checking out in side the motor? Is the run capacitor something that is easy to check?

[Tim Elett]

I was having morning coffee and was reading the post on the Laguna bandsaw Bill posted that you can hear the switch as the motor shuts down, I do hear this,do you still recommend checking out in side the motor? Is the run capacitor something that is easy to check?
Also I went out and ran motor with drum attached and motor didn't get warm at all,other than the vibration noise and getting hot under a light sanding load it is OK. THANKS.

[Tim Elett]

Also I went out and ran motor with drum attached and motor didn't get warm at all,other than the vibration noise and getting hot under a light sanding load it is OK. THANKS.
Removed motor,going to check around for used motor,motor shop is 125.00 per hr.Im guessing 1 hr plus parts I'll have 300.00,in a old motor.

[Paul F Franklin]

Tim, if it runs fine with no load, it probably is not the centrifugal switch or the starting cap.

It's unlikely the run cap would fail in a way that causes the motor to overheat, but you can test it if you have a multimeter. A search for "testing motor capacitor with a multimeter" will get you details.

Do you know if your motor is a totally enclosed fan cooled motor (TEFC)? I would expect it is on a machine like a sander. Such motors have a fan mounted to the shaft to help cool the motor. If something is wrong with the fan, it could cause overheating. Since the fan is outside the motor, it's possible for the shroud around it to get packed with sawdust too.

If it is not TEFC, it will have openings in the case to allow cooling air to flow through the motor. I would not be surprised to find the inside of the motor packed with sawdust.

[Tim Elett]

Thanks Paul,I did look that verry subject up and it says a bad run cap can cause vibration and over heating. It is a sealed motor,I assume from woodmaster it has sander on the tag.Will check out in morning,thanks for getting back with me

[Bruce Wrenn]

Myles: do not know what that is ,sorry
Richard:seems to run fine with no load but motor seems to get to hot ,ran one little board, couldn't keep hand on motor.

If it's a TEFC motor, the internal fan could have come loose from the shaft. Hot to your hand means nothing, using a gun, check temperature against manufacturers specs.

[Bill Dufour]

I have only had a few TEFC motors apart. Never seen one with an internal fan beyond fins cast into end of the rotator. Is that common to have separate internal fan blade?
Bill D

[Mike Henderson]

Tim, if it runs fine with no load, it probably is not the centrifugal switch or the starting cap.

It's unlikely the run cap would fail in a way that causes the motor to overheat, but you can test it if you have a multimeter. A search for "testing motor capacitor with a multimeter" will get you details.

Do you know if your motor is a totally enclosed fan cooled motor (TEFC)? I would expect it is on a machine like a sander. Such motors have a fan mounted to the shaft to help cool the motor. If something is wrong with the fan, it could cause overheating. Since the fan is outside the motor, it's possible for the shroud around it to get packed with sawdust too.

If it is not TEFC, it will have openings in the case to allow cooling air to flow through the motor. I would not be surprised to find the inside of the motor packed with sawdust.

The run cap just supplies power to the starting coil during running. That provides a bit more power to the motor. If you suspect some problem involving the run cap, just disconnect it. The start cap and the run cap are in parallel at start time. The centrifugal switch cuts the start cap out of the circuit but the run cap stays in. The run cap is smaller to limit the current through the starting coil when running the motor at full speed. The starting cap, being much larger, allows much more current through the starting coil. If the starting cap was left in the circuit the starting coil would overheat.

Mike

[Tim Elett]

So Mike is the run cap not needed,I will check and let you know.

[Tim Elett]

491709is this the correct setting on my meter? I am not getting a reading from eather cap. Is it possible that both are bad?

[Tom M King]

A starting capacitor has that resistor to bleed off the charge once it's dropped out of the circuit. It will have an effect on the meter reading when "testing" it. I can't read the scale on your meter on my screen, so can't comment on how you have it set. I use a meter that reads microfarads.

Found this that shows how the resistor has an effect on the meter reading.

https://www.youtube.com/watch?v=AYHuJuMPy_A

edited to add: Here's another video with the exact same meter I use, but the scale symbol should be the same on yours, if it has that capability.

https://www.google.com/search?q=check+capacitor+with+fieldpiece+meter&rlz=1C1KDEC_enUS921US921&oq=testing+capacitor+with+fieldpiece&aqs=chrome.1.69i57j0i22i30j0i390l3.10104j0j15&sourceid=chrome&ie=UTF-8#kpvalbx=_hy6bY-_ZJqWe_QachbyoBQ_27

[Jerry Bruette]

491709is this the correct setting on my meter? I am not getting a reading from eather cap. Is it possible that both are bad?

I think if both caps were bad your motor wouldn't start or run.

Did you replace both bearings on the motor?

Did you run the motor after replacing the bearings but before mounting the motor back on the machine?

When the bearing(s) were replaced how was the fit of the bearing into the motor end bells? You could have a bad end bell that's wallowed out and it could cause vibration. Was the wavy washer put back into the proper place?

You could ohm out the windings. If they're not balanced it could cause your motor to heat up.

If the motor runs cool and quiet when on the bench or with belts off I'd look at the drum. You could have something,bad bearings, causing the drum to not turn freely.

[Tom M King]

I agree with Jerry. My last post was just because I saw you were trying to test the cap.

[Mike Henderson]

So Mike is the run cap not needed,I will check and let you know.

It would be best if you start the motor unloaded. Since the start cap and the run cap are in parallel, removing the run cap reduces the current through the starting coil a bit at startup. So the motor will not have full starting torque. But the starting cap is much bigger than the run cap so it's not a big hit.

Mike

[Tim Elett]

Thanks for all the help I have learned a little bit about motors, I will find two new caps and let you know, I have nothing to loose at this point.

[Tim Elett]

Thanks for all the help I have learned a little bit about motors, I will find two new caps and let you know, I have nothing to loose at this point.
I contacted a motor shop to test the caps,thanks again.

[George Makra]

My two cents, get or borrow an AMP meter then check you amps against the nameplate FLA (which stands for full load amps)
Then you can determine if you do have a problem with the motor.

I know wide belt sanders as I help out at a local saw mill.

I will give you my take on wide belt sanders. NEVER EVER buy a used one.
Rarely if ever will you find one in decent shape.

These machines will create random vibrations. Sometimes its the sanding belt sometimes the machine needs a good cleaning.

I say all this cause your going down the internet knowledge path.

You would not cut a piece of lumber with out a measurement so why guess on electricity.

I suspect your motor is fine its just has a heavy load on it.

You say hot well how hot?

Heat is an enemy of electric motors,. they will get warm or hot and be fine. When you get above 120-150 degrees then your going into the damage area.
I say the range because it depends on the ambient temp.

I suspect you have a course belt on the sander and its packed with crud a good cleaning should help out.

[Tim Elett]

My two cents, get or borrow an AMP meter then check you amps against the nameplate FLA (which stands for full load amps)
Then you can determine if you do have a problem with the motor.

I know wide belt sanders as I help out at a local saw mill.

I will give you my take on wide belt sanders. NEVER EVER buy a used one.
Rarely if ever will you find one in decent shape.

These machines will create random vibrations. Sometimes its the sanding belt sometimes the machine needs a good cleaning.

I say all this cause your going down the internet knowledge path.

You would not cut a piece of lumber with out a measurement so why guess on electricity.

I suspect your motor is fine its just has a heavy load on it.

You say hot well how hot?

Heat is an enemy of electric motors,. they will get warm or hot and be fine. When you get above 120-150 degrees then your going into the damage area.
I say the range because it depends on the ambient temp.

I suspect you have a course belt on the sander and its packed with crud a good cleaning should help out.
I agree 100per cent although I threw on a old lathe motor I inherited [ 110 volt,long story] and no issues, this is a woodmaster 26inch model,a brother has a bigger woodmaster, and their is no vibration on his motor.
Again thanks I'll let you guys know what the motor man says..