I know this is an old post, but maybe it will help others looking for information.
I have the Craftsman 1/3-HP grinder models: 397.19580 & 397.19581.
They are Split-Phase single voltage (115 V), and use a Klixon start-up current style relay - 2CR14-224.
The relay is normally open. When the large starting current in the main/run winding circuit is sensed by the the relay coil (term 3 & 4) which is in series with the main winding, the relay contacts close (term 2 & 4).
The one end of the start-up winding is connected to the main coil's BLK wire in the coil pack.
When the relay contacts close the start-up winding is energized. The start-up coil is used to provide a boost to over-come the resting inertia of the rotor.
Once the rotor reaches between 65% - 75% of operating speed, the current through the main winding circuit is reduced to the point that the relay coil cannot over come the return-springs force, acting on the relay contact arm. With the contacts open, the start-up winding is no longer energized.
This should take about 2-3 seconds, if the relay malfunctions, the high current through the start-up windings (thin wires) may be damaged.
Here is a diagram I have made.
Klixon 2CR relays are no longer available.
You may find a suitable replacement here: http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_