Baldor bench grinder gets really hot!

[cowboy73]

I was out in the garage today. I decided to drag out the 6" Baldor bench grinder and sharpen some tools. I wasn't working it that hard and it seemed to get pretty hot on the motor case. Is it about ready to take a ****? I haven't attempted to dissmantle it yet to see what's going on inside. If its brushes are toast, can I replace them fairly cheap? I know that if the windings are messed up it probably isn't worth fixing. Any ideas before I take it apart or should just give up on it now and part it out?

 

[amguttin]

It very well could be bearings if you pull it apart look at bearings first If its a baldor i would bet the windings are fine

 

[Outlawmws]

let it cool and then run it up with no load and see if you can tell if the heat is from the ends and the bearings, or from the center and the windings.

 

[cowboy73]

Yeah, its definitely a Baldor. And I wasn't using the buffing wheel.

View media item 10607

 

[A_Pmech]

Define "hot".

If you can hold your hand on it for more than a couple seconds then it isn't running hot. Even the lowest temperature class of motor insulation is rated for a core temperature of around 200F.

 

[cowboy73]

I would say it runs around 160+ degrees F. Feels like touching the radiator cap on a car after having been driven for awhile. Definitely can only stand to touch it for a second or two.

 

[Conor]

Sounds like you need an IR temp gun to test the temp more accurately.

I got one on amazon for 15.00 shipped lol

160 Degrees doesn't sound too hot

 

[A_Pmech]

Around 160F is fine. About normal actually.

 

[cowboy73]

I'm just used to cheapy grinder I guess. It got warm but not like this. Hell, I may tear it apart just because! It's need painted anyway.

 

[cowboy73]

I ran the grinder with no load and it got hot in the middle and not at the ends. Well I started disassembling the grinder. Could this capacitor be failing and causing the windings to get hot?

View media item 18536

 

[torqueman2002]

I'm not certain of all the failure modes for a cap.

They typically are not that expensive.

You can test it with a Fluke 87 or similar DMM.

http://assets.fluke.com/manuals/87______umeng0800.pdf