Wissota grinder help

[Doc1976]

I piggybacking another post asking about this and realized starting my own thread was appropriate. I've got a technical question. I picked up this E7-P about a year and a half ago. Needed bearings, got that fixed and it's been awesome since. Week back I noticed it was taking much longer to get started than before. It also was drawing more power cause the shop fan running on the same circuit would slow as the grinder got up to speed. Now it won't get up to speed at all, runs real slow. Any suggestions as to where to look first? I know the circuit is fine, all other things used on that circuit are problem free.

https://imgur.com/qlneKW1

https://imgur.com/Hf5LBUO

 

[marinusdees]

I piggybacking another post asking about this and realized starting my I've got a technical question. I picked up this E7-P about a year and a half ago. Needed bearings, got that fixed and it's been awesome since. Week back I noticed it was taking much longer to get started than before. It also was drawing more power cause the shop fan running on the same circuit would slow as the grinder got up to speed. Now it won't get up to speed at all, runs real slow. Any suggestions as to where to look first? I know the circuit is fine, all other things used on that circuit are problem free.

https://imgur.com/qlneKW1

https://imgur.com/Hf5LBUO

There is a Wissota thread here, quite a few posts. I'll bet someone there can help.

 

[Doc1976]

That's where I first asked, but seemed more of a show off your grinder post rather than repair. Thanks though.

 

[seber]

Not really knowledgeable about these motors but I would check the capacitor for a short.

 

[Doc1976]

I'm hoping to get some time this week to take it off the pedestal and look it over. I don't remember if there were capacitors in this one. I think it had a contact switch in one of the housing cones though. I'm no expert on these motors though.

 

[Doc1976]

So I've found the switch on this grinder seems fine, as well as the power cord. I'm getting full voltage at the switch on both terminals when running (or trying to) I also noticed the motor cover getting very warm with only a little time trying to get it to get up to speed. Here's a shot under the cover, can I assume that's a capacitor there?

https://imgur.com/a/6MliHas

 

[Doc1976]

After some research, it appears to be a start capacitor. The numbers on it 124-149 bring web results for it.

 

[Catcher1984]

Sounds like a bad capacitor. Replace it with one with the same mfd/uf and VAC and you should be good to go.

 

[exmaxima1]

If the motor doesn't get up to speed the centrifugal switch will not cut off the start winding. That would cause a large current draw and heat up the start windings very quickly. I would try a new cap.

 

[Doc1976]

If the motor doesn't get up to speed the centrifugal switch will not cut off the start winding. That would cause a large current draw and heat up the start windings very quickly. I would try a new cap.

So if the cap is bad, will that cause the centrifugal switch to not function correctly? I've got a new cap being delivered today and if I need to get inside to the switch I want to do it while changing the cap.

 

[exmaxima1]

If the cap is bad and won't provide enough startup torque to get to running speed, the switch will never disengage. In that case the start winding remains energized (drawing lots of current) and overheats. Have you tried spinning the wheel to help it get up to speed? I used to always give my Baldor grinder with MT belt attachment a quick spin when I turned it on---it saves time and possibly prolongs the life of the grinder.

 

[Doc1976]

If the cap is bad and won't provide enough startup torque to get to running speed, the switch will never disengage. In that case the start winding remains energized (drawing lots of current) and overheats. Have you tried spinning the wheel to help it get up to speed? I used to always give my Baldor grinder with MT belt attachment a quick spin when I turned it on---it saves time and possibly prolongs the life of the grinder.

I haven't tried spinning it by hand. Your explanation makes perfect sense and those symptoms are exactly what I'm experiencing. I'll replace the cap tonight and see what happens. Thanksfor the replies.

 

[Doc1976]

If the motor doesn't get up to speed the centrifugal switch will not cut off the start winding. That would cause a large current draw and heat up the start windings very quickly. I would try a new cap.

Well unfortunately it looks like it's too far gone. The new start cap did not fix it, so I opened her up to check the centrifugal switch and this is what I found.

https://imgur.com/7bAv9t3

https://imgur.com/0XTczpw

https://imgur.com/vTGmuzY

 

[exmaxima1]

Ouch. I feel your pain.