I picked up 3 motors this afternoon from someone who cleaned out their
shed. I got a 1/6HP, a 3/4HP and a 1HP motor. The smaller ones are
just your regular motor, and they fire up without a problem and sound
good while running.

The 1 hp one doesn't work, though. When I give it power it just
buzzes. SWMBO told me the lights inside the house almost went out when
I was trying to get it to spin up. Do I need to replace the capacitor
or something to get it to work? It's a bit rusty, but the spindle
spins pretty easily.
This link is to a new version of the one I've got:
http://kingsolar.com/catalog/mfg/dayton/6k582.html

As to the others, would the 1/6HP one have enough guts to work as a
grinder or would it bog down too easily?

I'm hoping I can use one of these motors to power a small lathe that I
haven't built yet. I'd like to use the 1hp one, but I'm not sure it's
the right motor for that kind of purpose, so the 3/4 one will probably
go toward that.

I'd appreciate any help or advice, even if it's just a link to
somewhere with some good info.

-Nathan