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No, It isn't a great saw, but at least it worked. I can't even get it to spin now!

I was cutting 3/4" plywood with no problem. 3/8 X 6 tooth blade.
Then it was getting stuck, not wanting to spin. I can't get it to go.

It seems like it doesn't spin freely. What happened? I didn't change anything. The guides aren't tight, because they don't stay in place! The tension is at 3/8 where I had it. It WAS working. All I get is the dumb hum.

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Why be normal?

Took the table off. The inner guide on the bottom is froze. The other is fine. It doesn't turn any easier with the lower guides off.

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Why be normal?

Take the belt off the motor and saw pulleys. Does the motor spin then? Maybe it needs new brushes.

Have you taken the blade and the drive motor drive belt off to see if the upper and lower blade wheels spin freely? Does the motor shaft turn freely? If they do, energize the motor without the belt and blade and see if it turns. If a wheel is stuck it is probably the wheel bearing seized. If the motor won't turn it could be a motor bearing seized or worn out and that could cause the armature to jamb against the motor windings. Or the motor could have burned out, did you smell any smoke before it quit?

Often, bearings are pretty standard and if you take careful measurements you can even find them on Amazon, ebay or with a search engine. Most have ID numbers stamped in to the bearing you can look up. Same with guide bearings. Often easier to find and cheaper then going through the MFG.

I did a little looking and couldn't find a replacement motor on line. Hope you have better luck if that's the problem.

Carl's right, could be brushes but they usually last a long time.

Found a good selection of parts here--https://www.toolpartspro.com/jet-parts/jet-714000-(jwb-10)-parts.html Including a motor.

Good luck Ken.

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Brian R, Wood Mechanic
N8ZED

Ken,

Yea, What Carl said...

Also try to turn the motor manually from the spot it is stuck now. My first Craftsman table saw got a burned spot on the motor where the brushes are. Every time it hit that spot the motor would just hum like you explained with yours. I had to unplug the saw, turn the motor using the belt to get off of that bad spot. Once I did that it would work fine until it landed on that burned spot. I ended up just replacing the motor but when I called Craftsman about it they said it was because I was using and extension cord that wasn't rated high enough or it was too long for this saw.

Once I replaced the motor I bought the proper extension cord and never had that issue again. I eventually bought the new version of that saw but have always used my "big" extension cord, that was at least 30 years ago and the saw is still humming along.

Not sure if this is your problem but I now know to use a larger extension cord on anything that won't plug directly into the wall.


Hope you get it fixed,

Bob

It will turn, if you give it a little push. It will spin powered by the motor. When you turn it by hand it is NOT real free, and makes a dragging noise. I don't think a motor should make noise just spinning by hand should it?

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Why be normal?

Motor should be 99.9% noise free when spun by hand.

When you wiggle the pulley side to side there should be zero noticeable play.

If there is no play, try pulling the brushes as Carl suggested, maybe a brush is gone.

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Brian R, Wood Mechanic
N8ZED

i got the little drive belt off. The motor is free, and runs quiet. The lower drive pulley must be a mess. I need to get one of those tools to take off the retaining ring with the two little holes. Then maybe I can see what is wrong in it.

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Why be normal?

Does the lower blade wheel, without the drive belt and blade make noise when you spin it? Or does the blade wheel have any play in it when you grab the wheel with one hand where the blade sits and push and pull on it show any play? Not in the spin direction, facing the side of the wheel, push and pull-in and out, there should be no play and no clicking sound. If there is any play or in and out clicking, that wheel bearing is no good. Check the other wheel bearing too. Remember the upper wheel isn't stationary and will flop around top to bottom w/o blade tension. You are looking for side to side play.

Still a chance the motor bearing is bad so do the same with the pulley/shaft on the motor. It may run smooth and quiet without the belt side load on it. Especially if the blade wheels are quiet and tight.

The motor shaft spins lots faster than the blade wheel pulleys and if it is a bearing issue, the one on the motor shaft just behind the drive pulley would be most likely to wear out first.

There really isn't much to a bandsaw to go wrong. Usually blade wheel bearings or motor bearing on pulley end of the motor shaft.

Any noise or play = bad bearings. If it stopped the saw they should be easy to ID. Unless a brush is gone and the brush holder is jambed against the armature contacts.

It will be easier to find the problem with the wheels in the machine cause you have the machine to hold the bearing race center. The bearing can be bad w/o any visual indication unless it's totally worn out.

If you find the bad bearing you can get the "C" clips off with an awl and a screw driver and a little persistence. A little harder to put back on some times, but you don't necessarily need a special tool.

Keep digging, you will find the problem.

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Brian R, Wood Mechanic
N8ZED

Yes. The lower pulley is noisy, and doesn't spin real free. The top one spins freely. Probably bad bearings. Thankfully the motor seems fine. The thrust bearings, that I now see are adjustable, are stuck, at least at the bottom. I have no clue how to get that one out! The adjusters are a weak link. And the bearing I guess.

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Why be normal?

Hey Ken

I'd be happy to try and help you with this but maybe we should take it off line. So it doesn't drag out on the forum.

I'll PM you my email address and if you send some pics to me I'll do what I can to help. (PM sent)

Brian

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Brian R, Wood Mechanic
N8ZED

If your saw has an induction motor the fault is most likely caused by the start / run capacitor. These are usually in a plastic box fastened to the motor and often swell or split. I`ve had them go on both my record bandsaw and grinder. The performance on both gradually deteriorated until they didn`t run and just made a humming noise.
If it is the capacitor the good news is that they are readily available on Amazon.