Places to get parts(starter relay) for older(1960) ShopSmith

[DarrellLamb]

Sorry, I am a newby, Just purchased a machine and it turns for about 3 seconds then trips breaker. I am in the process of doing a thorough cleaning. It is getting better but still tripping.

[br549]

Welcome. A few questions to help diagnose the problem:

1. Are you sure the breaker is good, adequately sized, and not overloaded with other equipment or loads running at same time? (15 amp min, 20 amp preferred).
2. Have you tried on more than one circuit?
3. Is circuit GFCI protected?
4. Are you plugging directly into receptacle, or using an extension cord?
5. Did you see it start and run before you bought it?
6. Which model is it, and what is motor size (hp) and motor brand?
7. Is speed control set to "Slow"? If not, with power off and unplugged, manually turn spindle (attach sanding disk to make easier to turn) while dialing speed control down.

[wa2crk]

Are you trying to start it in "fast" speed setting? Of so unplug the machine and using the sanding disc and slowly turn the disc while setting the machine to "low" speed. I know some things about electric motors but there others hetre who are Very familiar with them. Excessive drag on the motor while it is starting will cause breakers to trip. Try disconnecting the drive belt from the motor and then try again. If the motor runs OK the problem is most probably external to the motor. Bad and or seized bearings are also a problem. Please let us know how you get along.
Bill V

[garys]

If you need parts, the best place to get them is a local electric motor repair shop. They stock just about anything you need to repair or rebuild old motors. If you take in the bad parts or motor, they can usually fix you up on the spot or repair it in a few days.

[DarrellLamb]

Thanks all for the reply. Lady I bought it off of informed me of the troubles it was having on start up. I was thinking on the line of a starting capacitor. I took it completely out of the head stock unit(for NO drag).Directly into outlet on a 20 AMP breaker. Tried and ran for about 3 seconds then trips breaker. Tried that a few times. Took starting relay apart to check for dust or corrosion. Motor seems to OHM out OK. Windings appear to have been heated(darker grayish color with a burnt motor smell). Took motor COMPLETELY apart to check bearings and blow out with air. Put back together for another try. Now runs for about 8 to 10 seconds before tripping breaker. Still got hopes, just not sure what will happen in the future. Again, thanks. Always ready to learn more.

[DarrellLamb]

Sorry guys, it is a GE 3/4 HP.

[JPG]

When you took the start relay apart did you check if the relay armature moved freely and if the contacts were NOT stuck closed?

I suspect the start relay is NOT disconnecting the start circuit.

A quickie check would be to quickly disconnect the start capacitor immediately after it starts.(either wire will do[carefully!!!!!!] to see it it still trips the breaker.

I am curious how you measured the motor winding(s) resistances.

Burnt smell is not a good sign.

[DarrellLamb]

JPG, thanks. Inside the start relay all seemed fine, clean, and worked freely.
I checked the winding with continuity(sp) by going from each lead in to ground and body, and lead to lead. As far as the capacitor, I think I'll just take it to a shop and have them check it or just replace it. I'm not much on pulling wires while they are energized in close quarters. Thanks again.

[P89DC]

What's a starter relay? Is that different than the centrifugal switch? Just interested and the google isn't bearing fruit.

[JPG]

What's a starter relay? Is that different than the centrifugal switch? Just interested and the google isn't bearing fruit.

The starter relay performs the same function as the centrifugal switch.

Rather than inertial rotary motion, the start relay responds to the voltage created by the armature rotating in the magnetic field created by the energized stationary run windings. Once the voltage exceeds a threshold value the relay picks and opends the relay contacts.