Actually, the CI&L had attempted to begin dieselization prior to WWII with the purchase of EMD FT's and yard switchers. However due to the Monon's inability to arrange financing, the order for the FT's had to be cancelled. The first F-3 orders were actually place by the Monon Trustees prior to the reorganization. At that point in time the EMD road freight units had already established very enviably performance reputation while Alco had yet to field the first FA models. If the Monon wanted a proven product wilth reasonable delivery times, the F-3 was the only game in town. Once the Monon had committed to the F-3, procurement of the BL-2 was an operationally attractive choice since the BL-2 was basically just a F-3 in different attire.
The purchase of the Alco C-628's is a bit more difficult to understand given the outstanding performance of the first generation EMD units on the Monon and the rather close relationship the railroad and builder had enjoyed between 1942 and 1963.
The C628 were of course purchased with the intent that they would almost exclusively power coal movements between Louisville and Michigan City. Given the planned service, there were three potential players, the 2750 hp Alco C628, the 2400 hp EMD SD-24 and, the 2500 hp GE U25C. At the time, GE locomotive line was still a bit of an unknown and the SD-24 was at the end of it's production life. Clearly the Alco C628 offered the most horsepower and had attracted a geat deal of favorable interest among various railroads. On paper, the C628 looked like a winner. Given the service the C628 were orginally intended to perform and the highly favorable C628 specifications, the Monon's purchase of the Alco product made sense at the time.
Once the dream of transforming the Monon into a coal conveyor failed, it unfortunately became apparent that the Alco C628 was not the ideal locomotive for the Monon's traditional system wide freight operations. Faced with the desire to dispose of the C628's and acquire a locomotive design more suited to the Monon's operational needs the road really didn't have many options. By the time the Monon wished to dispose of the C628's you could count on one hand the number of roads that might even have a passing interest in in Alco power even at firesale prices. Clearly, neither EMD or GE would have affording any kind of favorable tradein credit for three year old Alcos. Given the above, the only viable route open to the Monon was to hopefully strike a deal with Alco to take the C628's on trade for C420's.
The purcase of the U23B's after Alco had left the locomotive businees was quite logical since electrially, the U23B and C420 shared many common componets.
The Monon's Alco RS-2 were rebuilt using Alco componets. During the rebuild, the horsepower was rased from the orginal 1500 to 1600.
Steve
