I'm wondering if it just isn't how 493 always sounded or if they did something to 493 that they didn't do to 473. Not all oil burners have a muted sound. Some are quite loud actually. Here is a video I shot at the Black Hills Central Railroad last July. 108, the engine in the video, is one of the loudest steam locomotives I have ever heard and it also burns oil. The second video is of SL&RG 18 on the Rio Grand Scenic, also an oil burner. Both are quite loud and oil burners. (Second video isn't mine)
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