What's Wrong with my Mark V Motor??

greensngravy · Post by **greensngravy** » Sat Apr 13, 2013 4:00 pm

I have an old Mark V I bought on CL, and initially it was working well - good speed, etc. Lately, it has trouble getting up to speed before the breaker trips. I took the housing off and held onto the motor sprocket to give resistance while turning the motor on (and belt off), and the motor doesn't seem to have much power at all. I can keep it from rotating easily with the switch on.

Any ideas? Should I just assume the motor is shot and get it rebuilt?

Thanks,

Scott

beeg · Post by **beeg** » Sat Apr 13, 2013 4:34 pm

When was the last time ya lubed the SS?

dusty · Post by **dusty** » Sat Apr 13, 2013 4:47 pm

beeg wrote:When was the last time ya lubed the SS?

I normally agree with you regarding lubrication (or lack thereof) as a cause but not this time. If the motor can be restricted by hand, lack of lubrication is not the issue. The motor apparently has no torque and my first guess would be windings (not developing an adequate field strength).

If windings are shorted, they can be fixed by rewinding but that is probably more expensive than finding a replacement motor.

Good luck with this. I hope I am wrong. If you do need a motor, consider Bill Mayo for a used replacement.

greensngravy · Post by **greensngravy** » Sat Apr 13, 2013 5:31 pm

How do I get in touch with Bill Mayo?

Scott

beeg · Post by **beeg** » Sat Apr 13, 2013 6:40 pm

greensngravy wrote:How do I get in touch with Bill Mayo?

Scott

He's a member here, this should be his email address or if ya find one of his posts you can PM him

bill.mayo@verizon.net
His user name is billmayo

here's one of his posts. http://www.shopsmith.net/forums/showpos ... ostcount=4

joshh · Post by **joshh** » Sat Apr 13, 2013 7:05 pm

Since this is an induction motor, could being packed with sawdust dampen the magnetic field causing a loss in power?

wa2crk · Post by **wa2crk** » Sat Apr 13, 2013 8:09 pm

I might suggest checking the centrifugal switch first and then the starting capacitor.
Bill V

joshh · Post by **joshh** » Sat Apr 13, 2013 8:22 pm

wa2crk wrote:I might suggest checking the centrifugal switch first and then the starting capacitor.
Bill V

From my understanding the starting capacitor gets it moving and the centrifugal switch disconnects the capacitor once the motor is at speed? If the capacitor was bad, wouldn't the motor just sit there and hum? If the centrifugal switch was bad, but the capacitor was good, wouldn't it run anyway (at least until the capacitor burned up from extended time on)?

I'm trying to make sure I understand everything about these that I can before I reverse my AO Smith.

Culprit · Post by **Culprit** » Sat Apr 13, 2013 10:02 pm

joshh wrote: I'm trying to make sure I understand everything about these that I can before I reverse my AO Smith.

Here's a link to my thread on reversing my 1955 AO Smith, in case you haven't seen it yet: https://forum.shopsmith.com/viewtopic.php?t=9548

And here is a link to another thread with some good reversing info: https://forum.shopsmith.com/viewtopic.php?t=9417

If you have any questions, let me know.

joshh · Post by **joshh** » Sat Apr 13, 2013 10:46 pm

I hadn't seen the second link, thank you!

Is my logic above way off?

Shopsmith Forums

What's Wrong with my Mark V Motor??

What's Wrong with my Mark V Motor??

Thanks for the advice.