LukeG

I've tried digging around and I can't figure out a solution for this. Was hoping you guys might be able to help.

I have a WEN 3970.
About 2/3 of the time when I start it, the motor tries to turn but the blade doesn't move. I've found that if I turn it off and manually rotate the belt by hand and then turn it back on I can get it running. I've tried adjusting the belt tensioner and got the drive belt as tight as I can by hand. Nothing seems to fix it though. Any ideas?

Erat

iTrader: (5)

What is slipping? Drive belt on motor / wheel or the blade on the wheel?

Is the drive belt making proper contact? V belts need to make contact on the sides NOT in the root / bottom.
Is everything dry?

LukeG

It's weird as there is nothing slipping. The motor is trying to turn and the belt or blade seems like it is being bound up somewhere. I'm going to go over all the bearings tonight and make sure they are turning freely. Is there anything I should use the clean up all the metal shavings other than a dry rag and air?

Erat

iTrader: (5)

Don't want it too tight either.

Should be able to spin everything around by hand. Air rag and brush should be all you need.

LukeG

Thanks! I'll look it over and report back tonight.

Erat

iTrader: (5)

Wait.

110v motor. I'm assuming it's got a starter capacitor on it. Now that I reread your initial post I think that could be your problem.
Also sort of verified that when you give it a push it takes off.

It should fire off nice and fast. The motor should be able to overcome the belt if it is being bound up.

LukeG

Yeah, it's a 110v. I can replace the capacitor if need be. I'll try to clean it first and see if I can find anything.

Erat

iTrader: (5)

If you have a DDM you can set it to ohms. If it's open or inconsistent readings it's smoked.

Make sure you disconnect obviously and short it out to discharge it first. I've been nailed before it isn't fun.

It should be labeled with the information to track down a new one if bad.

LukeG

You were spot on. Old capacitor looked very rough. Ordered a new Dayton replacement from Grainger. Will update if it fixes the issue but after researching more it sounds like it is the capacitor.

TurboTim

iTrader: (9)

Came here to say starter capacitor. I just changed one on a pool pump motor.

LukeG

So that didn't go as planned... got the new Dayton capacitor installed and the bandsaw started right up and worked great for about 2 minutes. Then POP, the capacitor exploded. I looked everywhere on it for a polarity + or - and couldn't find anything. Assumed it could be installed either way, but apparently not. Next plan is to order two capacitors and if it blows up again just install the next one opposite of the first.

LukeG

Called Wen just for the hell of it and they are sending me a new capacitor. Getting confirmation now with one of their techs about the polarity.

They did confirm it has to be oriented properly with polarity. I'll just install it the same way as in the picture and hope for the best.

Erat

iTrader: (5)

Yes. Sorry I failed to mention that.
With that being said we all learn from our mistakes.

TurboTim

iTrader: (9)

Oh, I didn't know that. I guess I lucked out on that 50/50.

LukeG

All good! I figured if polarity was an issue it would be marked on the capacitors. No marking on either anywhere. Lesson learned!