Tricia ,
Another thought on your controller. Take the cover or housing off of it and clean it good. Make sure the contacts are clean and the wire connections tight.
Dirt, corrosion, burned contacts all will increase resistance and therefore heat.
Pat,
Just for curiosity sake I checked 3 controllers this morning. An electronic from Sew-Classic was rated at 1.2 amps, and two that came with Japanese machines were rated at 1 amp. The motor on the machine with the 1 amp controller does not list the amps, just the watts, 140.
I have several with motors like this. Is there a conversion method to determine how many amps 140 watts is?
Joe