Built for the Northern Pacific in 1917 as Class W-3 #1762 at Alco's Dunkirk, NY, works, this Mikado type (2-8-2) locomotive was acquired by the Spokane, Portland & Seattle in 1944 where it became Class O-3 #539. A total of eleven NP Mikados were bought by the SP&S from 19225 to 1944.
When I first published this page, I incorrectly described it as ex-Lake Superior & Ishpeming Consolidation (2-8-0) type #14. grand1 corrected me on this error in March 2020. He also advised that, at that time, #539 had recently been bought by the Port of Kalama in Washington State, and was then on its port property.
Built as a coal burner, #539 was 77' ½" long, with an engine wheelbase of 35' 3" and driver wheelbase of 16' 6", weighing 320,000 lbs, 240,500 lbs on its 63" drivers. Equipped with Walschaert valve gear, it has 28" x 30" cylinders. The grate is 70.4 sq ft, the firebox 325 sq ft. Operating at a boiler pressure of 180 psi with a total heating surface of 4,437 sq ft, including 846 sq ft superheating, it delivered 77,120 lbs tractive effort.
After purchase by the SP&S, the engine was converted to burn oil.
