Tags: Locomotive.
The ALCO DL420 was the prototype ALCO S-5 switcher diesel-electric locomotive.It was built in August 1951 using an early six-cylinder 251 engine rated at 800 horsepower (600 kW) and RS-3 subassemblies in its construction. It rode on two-axle trucks having a B-B wheel arrangement and was the first ALCO switcher with a front radiator opening. This one-of-a-kind unit spent its time at the Niskayuna test facility and then at Schenectady as a shop switcher (#6).