I’ve seen the title tunnel motor for locomtive before. What does this mean? Jon
“Tunnel motor” was the term applied to EMD SD40-2 (SD40T-2) and SD45-2 (SD45T-2) locomotives that had the radiator air intakes moved to the lower part of the hood, like every other manufacturer. With the air intakes near the top of the locomotive on EMD’s the air taken in in tunnels was so hot from exhaust gases that the radiators overheated. The reason only EMD had to make “tunnel motors” was that Alco, Baldwin, Fairbanks-Morse, and General Electric Diesel-Electrics had the radiator air intakes already on the lower part of the rear hood!
Interestingly, EMD adopted the “tunnel motor” style of air intake on its GP15’s. The “T” in GP15-T stood for “Turbocrarged” not “Tunnel motor”