A spring saddle over the third driving axle on the fireman's side of locomotive 4501 broke near milepost 147, 13 miles north of Somerset, Kentucky, on August 23, 1966, during 4501's inaugural excursion run. After assessing the damage, the locomotive moved slowly to Somerset, where it spent the night. A replacement spring was sent by train from the Tennessee Valley Railroad Museum in Chattanooga; a saddle was located in the weeds at Stearns, Kentucky, where the locomotive operated from 1948 to 1963. With equipment and crews assembled, repairs (see photo) were completed at 8:50 the next morning and the train quickly resumed its journey. A main driving spring is located over each driver journal. It absorbs road shocks like the springs of your car. It rests on a saddle to connect it with the journal. A large crowd was at the station in Knoxville to greet the train, which arrived a day behind schedule.