Missouri-Kansas-Texas AS-16m #138 at Kansas City, Kansas, August 15, 1965, photo by Chuck Zeiler
Thomas Berry left a comment below identifying this as a Baldwin AS-16, so I started researching that fact in the book, Diesels From Eddystone, The Story Of Baldwin Diesel Locomotives, by Gary and Stephen Dolzall. According to the book, Baldwin delivered eight AS-16s (road #s 1571-1578, c/n 74891-74898) to the MKT in September-October 1950, only four months after the order was placed, as part of Katys push to dieselize all principal passenger and freight operations. They went to Parsons, Kansas and were placed in service hauling freights to St. Louis. These AS-16s were unusual in that they employed cast frames, the only AS-16s so equipped. Subsequent units would use a one-piece welded frame with end steps and pilot faces permanently attached. Only the very bottom of the pilot was a removable, bolt-on section. In 1952, Katy received six more AS-16s (ordered October 1951, road #s 1579-1582, c/n 75431-75436). All these units had Westinghouse electrical gear (370 series traction motors and 471 series main generators).
In 1952, Westinghouse began to contemplate discontinuance of its heavy electric traction equipment. Baldwin protected itself with a request to General Electric to design a main generator compatible with the 625 rpm 608-series diesel prime mover, and GEs answer was the GT-590 main generator, which would feed power to GE 752-series traction motors. Using GE traction motors required larger traction motor blowers, so Baldwin re-designed the frame, lengthening it by six inches, and the long and short hoods were raised to within two inches of the cab roof. Actual application of the new design to orders was piecemeal because Baldwin used Westinghouse stock as long as supplies lasted.
In 1953, only 21 AS-16s were built, four went to Katy (road #s 1587-1588 c/n 75341-75342, and road #s 1787-1788 c/n 75694-75695). Katy 1787 and 1788 were equipped with steam generators and powered the Katy Flyer between Parsons and St. Louis. The Katy units were built to the old design with Westinghouse gear, and as it turned out, only two heavy road switchers were built with GE gear, although Baldwin purchased enough GE gear for 22 units. The GE gear was sold when Baldwin exited the locomotive business in 1956.
Between 1956 and 1960, the original power plants of Katys Alco FAs and RS3s, and Baldwin switchers and AS-16s were discarded in favor of EMD 567s. The AS-16s were repowered with 567C V-16s rated at 1500 horsepower, and re-equipped with GP9-style long hoods between February 1958 and March 1960 under EMD rebuild order numbers 8528, 8541, 8542, 8553, and 8564. The units were also renumbered about this time, with 1787 becoming 124, 1788 was retired, and 1571-1586 became 126-141. In 1972, Katy sold all 17 remaining units to Precision National Corp., Mt. Vernon, Illinois, and 13 of the repowered AS-16s received a surprise extension to their careers when they were leased beginning in September 1972 then purchased outright by the Chicago & North Western Railway, becoming #s 1485-1495, 1497-1498, and were assigned to Green Bay, Wisconsin, and were finally retired in 1981. MKT 139 (ex MKT 1584) was intended to be C&NW 1496, but was scrapped by PNC prior to sale to C&NW. This particular locomotive was scrapped by C&NW at Oelwein, Iowa, July 1980.