Band saw motor help

[Andy Hutyera]

I have a 36 inch band saw powered by a three hp 220 single phase motor. The motor starts fine but does not come up to full speed. It acts like it's staying in a startup mode. It is not coming up to full power as it slows down as soon as you try to make a cut. The saw itself runs free to hand turning the drive wheel so the bearings are not overloading the motor. I'm guessing that somehow the capacitor start system is not kicking out but really don't know what to look for. Any help would be greatly appreciated.

[Rod Sheridan]

Have you ruled out mechanical issues such as loose belts and pulleys?

I would start there, as it's the most likely cause given your symptoms.

Does the motor speed vary?

Regards, Rod.

[John TenEyck]

The centrifugal switch is likely not opening so the motor start winding never disconnects. The switch is probably gunked up with sawdust. It's under the bell housing at one end of the motor; I'm not knowledgeable enough to know if it's always at the shaft end, the opposite end, or there is no standard. Anyway, you might just be able to clear out the sawdust by blowing compressed air into any openings in the bell housings, without disassembling anything. If not, you'll have to pull the motor out and figure out which end has the switch and clean it out. Could be wrong, but I'd bet that's it.

John

[Rod Sheridan]

The symptoms indicate low power, that doesn't indicate that the start winding is staying energised............Rod.

[Myk Rian]

If the centrifugal switch is the problem, don't run it long like that. Recipe for a burned up motor.

[Andy Hutyera]

Many thanks for all of the support! Upon closer inspection it looks like the culpret is the leather drive belt. With better lighting I confirmed that the motor is actually coming up to full speed. That was after I gave the motor a good clean out with compressed air. It looks like I need a new drive belt. So, I'm looking for a source for a leather drive belt. It's about four inches wide. I may have to head over to Amish country.

Thanks again folks!!

[Sal Kurban]

I suggest you try Tractor Supply or a farm store and consider rubber belts. These are much stronger than leather belts and are not susceptible to humidity, weather etc. They are usually used in balers and it is easy to find lacing tools on ebay or CL to join them. They last forever and are inexpensive.
Sal.