Shopsmith Forums

On my Mark V 500, the motor will occasionally "stall" when trying to start--maybe a dozen times in the ~45 years I've owned it.

This happens when I've got the headstock in the vertical, drill press configuration. When the power switch is turned on the motor just hums and won't turn. Using the headstock in this vertical orientation seems to cause sawdust that has collected in the motor housing to fall into the end of the motor that contains all of the electrical contacts and cause the issue. My only solution has been to remove the motor and take the motor bearing cover (opposite the drive end) off and clean the electrical contacts / mechanisms of collected sawdust. I mainly suspect the centrifugal capacitor switch.

Is this a known issue and is there any way to mitigate it? Or is dismantling and cleaning the motor considered somewhat normal maintenance?

Occasional blowing out the accumulated crud may help prevent this.

I'm kind of surprised that this isn't more of a common problem. It does require some effort to remove the motor to clean it, but I guess every year or so shouldn't be a big deal.

As JPG said,

Occasional blowing out the accumulated crud may help prevent this.

If done often enough, blowing the dust and debris out of the Headstock will help keep the "crud" out of the motor itself. This will also help keep the dust from "gumming up" other moving parts in the Headstock. It should be done each time you lubricate the Headstocks parts.

It sounds like you have had to open up and clean inside the motor about every four years which may not be a bad idea anyway.