This engine was built by the American Locomotive Company of Schenectady, N.Y. in August 1946. It was built as model RS-1, serial number 75117. It was originally numbered Minneapolis & St. Louis D-946 (early diesels on this road were numbered according to the month and year the unit was placed in service), later renumbered 946 and finally 217. In 1960 it was sold to the Sydney & Louisburg (later Cumberland Railway Company, and Cape Breton Development Corp, Devco), which was beginning to phase out its steam power. The M&StL supplied seven RS-1 engines to the S&L for service, plus another for parts. The RS-1 was replaced by new power from the Diesel Division of General Motors of Canada and the Devco fleet was dispersed in the early 1980s.

The RS-1 model was the first mass-produced road switcher built in the U.S.A. The production ran from 1941 to 1960 with very few changes in the basic design. The power plant was a 6-cylinder 12.5" bore 13" stroke model 539 diesel, turbocharged for 1000 HP. The traction motors were GE 731. All electrical equipment was made by General Electric.

Sadly, this engine and its sister, 209 were destroyed in the 1994 fire.