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Mk5 motor is dead

Posted: Mon Jan 22, 2018 12:54 pm
by trainguytom
It's been a long time since I've been here. Life sometimes gets in the way of woodworking. Moved from Wisconsin to Florida, lost my basement shop and piled everything up in my garage for 2 years and finally got a shop built last summer. I've been gradually unpacking and setting things up. a while back, I was using my 510 (I think doing some disc sanding). All was going fine.Then, after I had turned the machine off, I went back to continue. I turned on the switch, and nothing. No spin, no hum, no apparent power.
My first thought was look for the obvious. That the switch went bad, or the cord, or the outlet.
I got out a spare plug/cord & bypassed the switch right the motor leads and still nothing. No hum, just dead.
I'm wondering if I'm missing something obvious here. So I thought I'd turn to the SS brain trust here before I dig deeper. As a last resort, I do have a spare motor I can switch to, but this ran so good right up until it didn't, so I'm hoping to save it.

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 1:58 pm
by rjent
another obvious question, but have you checked your outlet? Plugged a light into it or something? From what you have said, I suspect source, not machine.

If you have a volt (multimeter) start at the outlet and go from there.

Hope you find the problem!

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 2:15 pm
by trainguytom
Outlet power is fine, and since I ran from the outlet direct to the motor leads bypassing the switch, I have power to the motor, right? If that's the case, what are the internal motor issues that might be at work here, Or should I just switch out my motor & not waste time.

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 2:18 pm
by bcralph
rjent wrote:another obvious question, but have you checked your outlet? Plugged a light into it or something? From what you have said, I suspect source, not machine.

If you have a volt (multimeter) start at the outlet and go from there.

Hope you find the problem!
I was thinking either the outlet or the breaker itself. I had an outlet i had items plugged into that would pop the breaker quite often. i have since fixed this problem.

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 3:21 pm
by beeg
trainguytom wrote:Outlet power is fine, and since I ran from the outlet direct to the motor leads bypassing the switch, I have power to the motor, right?

Are you sure you have power at the end of the cord? Have ya tested it?

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 3:44 pm
by dusty
Because of the way you describe the problem, I suspect that the issue is internal to the motor. First candidate for indictment would be the centrifugal start switch. I would suggest you start by blowing all the dust out of the motor with compressed air (not just a vacuum cleaner). If dust/dirt has accumulated on the contacts of the start switch that could cause your exact symptoms.

No hum, no motion, no run, etc. You said that you "hot wired" from a live outlet directly to the two hot wires (black and white or blue and white) to the motor. That eliminates the switch and power cord (you did use a different cord? - right) as suspect..

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 6:50 pm
by jsburger
dusty wrote:Because of the way you describe the problem, I suspect that the issue is internal to the motor. First candidate for indictment would be the centrifugal start switch. I would suggest you start by blowing all the dust out of the motor with compressed air (not just a vacuum cleaner). If dust/dirt has accumulated on the contacts of the start switch that could cause your exact symptoms.

No hum, no motion, no run, etc. You said that you "hot wired" from a live outlet directly to the two hot wires (black and white or blue and white) to the motor. That eliminates the switch and power cord (you did use a different cord? - right) as suspect..
I believe if the start switch is open the main stator windings will still hum. Also if that is the case you should be able to apply power and spin the motor by hand and it should run.

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 7:15 pm
by JPG
Time for a continuity checker(ohm meter).

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 8:13 pm
by trainguytom
I think tomorrow, time permitting, I'm just going to bite the bullet and take the headstock apart and nitpick through it making sure I have checked all the obvious stuff and then blowing out the motor. Beyond that, I may just swap in my extra motor & be done with it. I'll let y'all know if I find something interesting. Thanks

Re: Mk5 motor is dead

Posted: Mon Jan 22, 2018 9:17 pm
by jsburger
trainguytom wrote:I think tomorrow, time permitting, I'm just going to bite the bullet and take the headstock apart and nitpick through it making sure I have checked all the obvious stuff and then blowing out the motor. Beyond that, I may just swap in my extra motor & be done with it. I'll let y'all know if I find something interesting. Thanks
Before you do that take the belts off and apply a known good power source to the motor an spin it by hand. If it runs then the start switch is the problem. If not the motor wingdings are suspect. As JPG says a continuity check will tell.

If the motor did not smoke it is hard to believe it is the motor itself. Other than a broken connection somewhere.