Jet 1014 Capacitor Problem

[plano_harry]

Finally smoked the capacitor on my Jet. Didn't like the $24 option from the factory so I went to Granger and picked up a 25uf 250 VAC cap to match the specs on the old one for $5. Installed it and I was back in operation. After about an hour and 6-10 starts, the new one is smoking. I read something on another forum about problems with the switch not taking the start cap out of the circuit and causing it to overheat. Is something wrong with the motor that is cooking the cap? Help! I haven't been able to finish a pen in over a week!

 

[Lucky2]

I'm not sure, but maybe you should try the $24.00 one from the factory it could be different. Or call the manufacturer and ask them for some advise, even if you don't have warranty they still may be able to help you out.
Len

 

[ctubbs]

If your original cap was a 25 uf @ 250VAC, then, electrically, the new one should have been good to go. If for some reason the start switch, which is internal to the motor, is failing to open when the motor comes up to speed, then the cap will remain in circuit and draw excess current causing it to fail. How many wires are going into the motor? There should be three or more. If only three, one hot, one neutral and a ground, the switch will be inside the motor. If more then the switch may be a relay external to the motor. If it is outside then easy fix, fine it and replace or repair. Most likely, though, it will be located inside. Unless you are experienced with motors, I would not recommend trying to do the repair unless you just wish to learn.
Charles

 

[plano_harry]

Thanks Charles, that is helpful. I will take a look at the power switch.

Harry

If your original cap was a 25 uf @ 250VAC, then, electrically, the new one should have been good to go. If for some reason the start switch, which is internal to the motor, is failing to open when the motor comes up to speed, then the cap will remain in circuit and draw excess current causing it to fail. How many wires are going into the motor? There should be three or more. If only three, one hot, one neutral and a ground, the switch will be inside the motor. If more then the switch may be a relay external to the motor. If it is outside then easy fix, fine it and replace or repair. Most likely, though, it will be located inside. Unless you are experienced with motors, I would not recommend trying to do the repair unless you just wish to learn.
Charles

 

[aplpickr]

A good mechanic can fix start switch

The start switch and start winding are in series. The switch is closed making contact when the motor is stopped. At 3/4 speed it should open. When motor stops the switch closes with an audible click. If it does not click it is stuck or welded. This will overheat the cap causing it to swell.
To access the start switch: make reference marks on each end to help line up endbells and motor body. Remove non-shaft-end endbell. Clean or repair switch being sure that you haven't pulled any wires loose, Reassemble and tighten bolts while turning the shaft. Tighten opposite bolts in a staggered pattern. Tighten in about FOUR steps.

 

[ctubbs]

The start switch and start winding are in series. The switch is closed making contact when the motor is stopped. At 3/4 speed it should open. When motor stops the switch closes with an audible click. If it does not click it is stuck or welded. This will overheat the cap causing it to swell.
To access the start switch: make reference marks on each end to help line up endbells and motor body. Remove non-shaft-end endbell. Clean or repair switch being sure that you haven't pulled any wires loose, Reassemble and tighten bolts while turning the shaft. Tighten opposite bolts in a staggered pattern. Tighten in about FOUR steps.

If you do decide to open your motor, follow Bill's advice. He is correct with his info. When removing the end bell, do it over a light colored soft surface and watch for any washers that may fall out and which side was facing which way. they are in there for a reason and need to go back the way they came out. Take your time and all will work out, this is not brain surgery. If you have a camera, take pictures as you go along. they can be a real problem solver if you forgot just where that thing came from. DAMHIKT.
Charles

 

[TellicoTurning]

Finally smoked the capacitor on my Jet. Didn't like the $24 option from the factory so I went to Granger and picked up a 25uf 250 VAC cap to match the specs on the old one for $5. Installed it and I was back in operation. After about an hour and 6-10 starts, the new one is smoking. I read something on another forum about problems with the switch not taking the start cap out of the circuit and causing it to overheat. Is something wrong with the motor that is cooking the cap? Help! I haven't been able to finish a pen in over a week!

Harry,
How old is your lathe? If it's less than 5 yrs, likely still under warranty and Jet's very good about their warranty ... they sent me bearings for my 1014 about 3 years ago even though I'm not sure it was still under warranty... it was my son's before I got it and by now I've had it almost 8 years, plus they have fixed my big lathe a 1442 twice - once for bearings and once for a bad motor pulley... no charge to me either time... it is still under warranty until next year.

Give them a call, explain the problem and let them tell you about whether they can have it fixed or not... I'd do that before you open the motor... that might void your warranty.

 

[plano_harry]

Thanks

Thanks to Bill and Charles for the excellent repair description. I am a "fixer" so that is exactly what I was looking for. However, Chuck's logic got the best of me and I am going to do a warranty check when I get back home. I will update you on the outcome. I am always amazed at how helpful the IAP members are!

Harry

 

[plano_harry]

Just to close the loop on this for the benefit of those who may find this thread in the future --

• Didn't pursue the warranty - motor was 10 years old.
• Motor parts supply guys said it was a start cap so I picked up 2 with the same specs as the Chinese one I was replacing since they were only $3.60 each and cheaper than the gas to come back for another. Installed new cap under the cover and started turning again. Melted it as described above
• Opened motor case according to the guidance above. Didn't see anything that looked a centrifugal switch that was stuck, or any other type of capacitor cut out switch. See photos of inside of motor.
• Went back to motor parts guys and asked for a run capacitor, instead of a start. My clue was the 250 WVAC on the original cap, indicating working voltage AC - I read that this is a usually found on run capacitors. Parts guys scratched their heads and said to call them back and let them know if it worked.
• Installed on the motor - good as new! Several running hours later, no problems! Cap was completely cool :biggrin:

I haven't been able to find a run cap with the right specs that will fit under the little cover on the side of the motor, but that is not a problem for me. This is a nice industrial quality aluminum can (just slightly larger) Plenty of room to mount near the on/off switch. Sooo - if you cook your aging capacitor, find a local motor supply or Granger mail order and get a motor run capacitor for $5 -- or send $25 to JET's new owner and maybe get a smaller like the one that melted. :tongue: I don't mind making mistakes as long as other people learn from them.:biggrin:

Harry

 

[randyrls]

Thanks for the info Harry; Good to hear your lathe is working again!