I have a Dayton 1/3 H.P. motor Model no. 4M099C. It is a 220-230 volt motor. There are four wires coming from the motor. The purple is marked common, the black marked high, the blue marked med. And the red marked low. I want to connect these to run on 220. How do I go about connecting common and the two hot wires from a 220 cord to the correct wires of this motor?

The one hot wire goes to the purple common. The other goes to the one for the speed you want, the black for high speed. You could also wire it to the common of a 3 throw switch and be able to switch speeds.

Be sure to cap off the unused wires. They will be hot.