The U - Class was wide spread on the K & K (Austrian - Hungarian narrow gauge) system in southern Europe and always burned coal. Heard of one beeing re-built to oil in former Yugoslavia but could never proof the info. Boiler pressure is app 9-10 atmospheres if I recall right. Hp app 250 - 300 depending if superheated or not. App 25 still in service in Austria. Rode one some 6 weeks ago to get my "yearly requested engineer hours" for 2004. This engine is an earlier one with the water tanks not till front of boiler and a rather set back stack
B T W.
We in Europe call the gear Heusinger (after the inventor) gear and not Waldschearts (who made "only" some upgrading on it).
Steffen