While being an easy, sure footed locomotive to run, Virginia & Truckee ten wheeler 25 is rough on firemen. The locomotive was build as a coal burner with an extremely small firebox and a relatively small boiler. The conversion to oil made it difficult to maintain pressure. The fireman has to really anticipate and stay on top of the actions of the engineer. If you fall behind it's hard to catch up without smoking up the environment. At the Nevada State RR Museum we use diesel oil. Perhaps if we were able to use a heavier oil with more BTUs/lb she might respond better.