Mark V blade slowed then stopped

hnderson · Post by **hnderson** » Tue Jul 30, 2013 5:05 pm

I don't know how old this SS is. I got a rebuilt headstock about 8-10 years ago.

I've used it mostly for remodelling projects and it's been reliable until yesterday. I was cutting molding on edge. The motor bogged down as it always has when cutting anything thicker than 3/4". I got to the last couple of pieces and suddenly, the power cut way back. I removed the stock and turned it back on. It only went up to about 1/2 power. I could increase the speed with the dial but it wouldn't get close to it's original speed.

I left it overnight and turned it on briefly this morning. The blade moved but wouldn't rotate. I turned it off immediately.

There were no scraping sounds, just loss of power (or is there something putting too much resistance to the motor?)

Any ideas?

hnderson

JPG · Post by **JPG** » Tue Jul 30, 2013 10:02 pm

Try rotating the quill shaft by hand, and 'report back'.

hnderson · Post by **hnderson** » Wed Jul 31, 2013 1:25 pm

I can easily rotate the blade.

JPG · Post by **JPG** » Wed Jul 31, 2013 1:53 pm

Not Good!:(

I do not have an explanation for the 1/2 power symptom, however the move but not run is likely the start switch or less likely the start capacitor.

Either require motor removal and disassembly.

Do you want to go there?

Another preliminary 'check' would be to mount the sanding disc and get it spinning by hand and 'briefly' turn the motor on while it is rotating. Look for an attempt to 'rev' up. Leave it set to saw/joint speed setting. I said ***'briefly'*** turn motor on!!!! A couple of seconds max.

If it does 'rev up', the start circuit is likely the problem.

Over

Gene Howe · Post by **Gene Howe** » Thu Aug 01, 2013 9:38 am

Belt tension?
Mine worked loose and wouldn't resaw 5" wide oak. Easy fix. Hope yours is as easy.

JPG · Post by **JPG** » Thu Aug 01, 2013 9:49 am

Gene Howe wrote:Belt tension?
Mine worked loose and wouldn't resaw 5" wide oak. Easy fix. Hope yours is as easy.

BTW:D There is a difference between motor not running and the output shaft not turning!!!;)

So hnderson, which is it?

Gene has provided the solution to the latter.

dusty · Post by **dusty** » Thu Aug 01, 2013 10:24 am

It seems that no one does this but me but when I suspect that I might have a motor problem, I isolate the motor from all else. I would remove the drive belt and then either indict or clear the motor.

JPG · Post by **JPG** » Thu Aug 01, 2013 10:44 am

dusty wrote:It seems that no one does this but me but when I suspect that I might have a motor problem, I isolate the motor from all else. I would remove the drive belt and then either indict or clear the motor.

A freely rotatable output shaft does almost the same thing. One can feel the motor load(lack of) to determine if slippage is gross.

How does one describe that 'feel' to a newbie?

There are many things that I would do differently from those I suggest, but taking the beast apart is, for me, not the fearful endeavor that many who have not gone there before think it is.

Then there are times when no other approach is evident.

It shall be interesting to see where this thread leads us.

Hopefully to a fully functioning SS!

hnderson · Post by **hnderson** » Mon Aug 05, 2013 6:09 pm

I appreciate the feedback so far. I had to take my work to a local cabinetmaker to get the job finished in time.

Now I get to work on the Shopsmith.

I pulled the motor. I'm assuming that the wires came loose as I lowered the pan but there are two loose wires - the black and white. I went to the Shopsmith instructions on removing the motor and it says the blue wire from the motor should go to the top left post on the switch, the black from the cord to the bottom left, the white from the cord to a white lead to the motor.

Mine has a green wire going to the top left, yellow to the top right, both from th e motor. From the cord, the white and black are loose and a green is going to the motor.

Why such a discrepancy in the wiring?

dusty · Post by **dusty** » Mon Aug 05, 2013 6:33 pm

hnderson wrote:I appreciate the feedback so far. I had to take my work to a local cabinetmaker to get the job finished in time.

Now I get to work on the Shopsmith.

I pulled the motor. I'm assuming that the wires came loose as I lowered the pan but there are two loose wires - the black and white. I went to the Shopsmith instructions on removing the motor and it says the blue wire from the motor should go to the top left post on the switch, the black from the cord to the bottom left, the white from the cord to a white lead to the motor.

Mine has a green wire going to the top left, yellow to the top right, both from th e motor. From the cord, the white and black are loose and a green is going to the motor.

Why such a discrepancy in the wiring?

When you say that the green wire goes to the motor, I assume you mean it is connected to the motor housing. If so, the green wire is where it should be.

The other two loose wires are the power to the motor. This Sawdust Session video should have you back in operation. Check out items 1, 2, and 3 on the blackboard.

Hope this helps.