ALCO 251

New in the 251 was an intercooler for the turbocharger, which minimized temperature differentials and also benefited performance.

Many small improvements were made to the crankshaft, bearings, pistons, injectors and camshafts.

To avoid the problems caused by rushing the 244 into production, the 251 was put through an extensive testing process.

[1] A simple, safe design, it also offered a direct replacement for the aged 539, which was still used in switch engines and the ALCO RS-1 road switcher.

Engine manufacturing at Schenectady was terminated in 1962, after which all non-Canadian production was moved to Auburn.

[1] Engines for A. E. Goodwin, Alco's Australian licensee, were built at Auburn or Schenectady;[1] engines for Montreal Locomotive Works were, until 1961, assembled by MLW using parts supplied by Auburn and Schenectady.