The ALCO RS-3 is a 1,600 horsepower (1.2 MW), B-B road switcher diesel-electric locomotive. Manufactured by American Locomotive Company (ALCO) and Montreal Locomotive Works (MLW) from 1950 to 1956, and total 1,418 were produced. 1,265 for American railroads, 98 for Canadian railroads, 48 for Brazilian and 7 for Mexican railroads. The ALCO RS-3 has a single, 12 cylinder, model 244 engine.
North East Rails, http://www.northeast.railfan.net/diesel50.html , has more information about RS-3s. the N&W Historical Society Archives, https://www.nwhs.org/archivesdb/selectdocs.php?index=rs&id=128 , has over 60 historical documents related to the RS-3.