Alco RSD7 Builder List and Phases
- Phase I – January to February, 1954 – Alco Specification DL600. Two 2250 horsepower prototypes were built, Alco DL600 and DL601. They had General Electric GT586 main generators, GE752 tractions motors, and Alco’s turbocharged 16-cylinder 244G engine. They introduced the new carbody style that would be carried forward to the RS11, RSD12, and RSD15. The same Tri-Mount truck used on the RSD4 and RSD5 continued to be used, with single shoe brakes and two air cylinders per truck. Both air tanks were mounted one above the other on the same side of the fuel tank. Sand filler lids were square.
- Phase IIa – October, 1955 to January, 1956 – Alco Specification DL600A. These production units were built with the 16-cylinder 244H engine, and were rated at 2400 horsepower. They were a foot and a half longer than the two prototypes. Sand filler lids were now round instead of square. Phase IIa units have clasp brakes with four air cylinders per truck instead of two.
- Phase IIb – February to April, 1956 – Brake wheel is moved from inside the cab to a round recessed location on the front of the short hood.
Pennsylvania units had a pair of open boxes behind the cab on the engineer’s side of the unit for Train Phone and automatic train stop equipment.
|Year||Month||Railroad||Order No||Bldr No||Phase||Qty|
- ATSF 600
- ATSF 601
|1955||December||Pennsylvania Railroad 8606-8608||S3257||81745-81747||IIa||3|
|1956||January||Pennsylvania Railroad 8609-8610||S3257||81748-81749||IIa||2|
|1956||February||Chesapeake & Ohio 6800-6802||S3268||81901-81903||IIb||3|
|1956||March||Chesapeake & Ohio 6803-6810||S3268||81904-81911||IIb||8|
|1956||April||Chesapeake & Ohio 6811||S3268||81912||IIb||1|
- John D. Hahn, Jr., Pennsylvania Railroad Diesel Locomotive Pictorial, Volume 1: Alco RS Series, Withers Publishing, 1995, pgs 47-48
- Kenneth L. Douglas and Peter C. Weiglin, Pennsy Diesels 1924-1968: A-6 to EF-36, Hundman Publishing, 2002, pg 148-149
- Jerry Doyle, Chesapeake & Ohio Diesel Locomotives in Color 1949-1971, Chesapeake & Ohio Historical Society, 2006, pg 75
- Chesapeake & Ohio Diesel Review, The Chesapeake & Ohio Historical Society, 1982, pg 178
- John F. Kirkland, The Diesel Builders, Volume 2: American Locomotive Company and Montreal Locomotive Works, Interurban Press, 1989, pg 150-152
- old.atsfrr.org – AT&SF RSD7 roster
- Robert Lehmuth, American Locomotive Company Complete Works – Volume 8, pg 40, 49, 80, 99-100