The Hydro static test at 425 degrees Fahrenheit and an air pressure of 300 PSI has been performed already!
The next step is actual steam pressure testing which should not be a problem.
The crew is also converting the boiler from coal to oil by removing the ash pan and putting in a metal frame that the new burner is going to be mounted to.
Incidentally, they will be using Challenger #3985’s tender to facilitate the Big Boy #4014 completion. It is estimated that it will take about 3 years to complete the overhaul of Challenger #3985, during which time, Big Boy will be using #3985’s tender.
By the way, how many bolts do you think her boiler has?
Let us know if you have had the chance to see Big Boy under renovation at the Steam Shop in Cheyenne. We would love to hear about your experience.