So yesterday, while I was delayed an hour because they had to replace the ACS64, I was sitting in the fist car and got to hear a lot of the work crew's conversation. They referred to the said ACS 64 as the "motor," not the "engine" or the "locomotive." I am aware that an electric power unit i as called a "motor," but I don't know why this os the case. True, an "engine," such as a P42 is powered by an internal combustion diesel, but I call the internal combustion thingy that powers my car a "motor." This seems to be inconsistent with railroad usage. Anybody know the origin of this terminology?