Dan Robirds Wrote:
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> My guess:
>
> Look at the linkage to control the valve gear.
> There is little hope of keeping this in correct
> adjustment. If the valve gear control drifts, the
> efficiency of the engine is affected.
>
> The moveable steam joints would also be a
> maintenance issue. I wonder how well they tracked
> at higher speeds?
Walschaerts with that ungainly arrangement for reversing will still stay in better time than the Stephenson valve gear that everybody else was using back then. Your other points are well taken.
I thought that they went away from them because they were too small, not enough tractive effort.