The Restoration of Milwaukee Road 72

The design and purpose of an “F Unit”, as termed by the railroads, was to help bring upon the modernization and transition from steam locomotive power to the modern and more efficient diesel – electric concept. Locomotive 72 is a prime example of this particular transitional phase in both Indiana and America’s railroad evolution. The F Unit was a design concept by the Electro Motive Division of General Motors. In competition with other locomotive producers, such as the American Locomotive Company, the Electro Motive Division of General Motors experienced great success with the F Unit series design concept in both the freight and passenger locomotive industry.

Locomotive 72 was built in 1949 for the Milwaukee Road at the Electro Motive Division plant in LaGrange, Illinois. The locomotive served in the capacity of hauling freight over the Milwaukee Road System up until around 1981. In 1976, the locomotive was overhauled by the Milwaukee Road to work as a “slug mother”, or better known as a controlling unit of cabless locomotives, known as “B Units”. The locomotive was parked in a line of dead locomotives in the railroad yard of Bensenville, Illinois in 1981 upon the locomotive’s retirement.

In 1983, officials of the Indiana Transportation Museum made a trip to Bensenville, Illinois to examine a plethora of locomotives in search of the proper F Units to serve as power for the first Indiana State Fair Trains and other railroad operations, as the Museum was transitioning into the next step of development from a primitive electric railroad museum. Locomotive 72 was selected along with two other F Units, known as “A Units” like 72, and one B Unit, to be purchased at scrap value and moved to the Museum’s base in Noblesville, Indiana.

Upon the first Fair Train, two of the other F Units were selected for restoration and service. Locomotive 72 was not chosen due to the previously overheated block the locomotive contained. However, in 2007, a formal proposition for restoration was proposed and approved for Locomotive 72. Since the project’s conception, a large number of museum youth individuals have participated in the overhaul of this classic American example of railroad evolution under the guidance of the Museum’s Chief Mechanical Officer. On New Year’s Eve of 2011, the locomotive was fired for the first time in almost 30 years. This project has been essential not only to provide the Museum with another great attribute to the legacy of the caliber of restorations completed by the Museum, but to teach the next generation of the Museum the skills to maintain and preserve the art, science, and technological innovation of the railroad.

Please explore this webpage to see project updates and information regarding how you can donate time or funds to help the next generation of the Museum preserve the art, science, and technological innovation of the railroad.


Project Milestones


  • Locomotive is placed into shop, cleaned, and organized to begin project
  • Disassembly and replacement of locomotive cylinders, rods, and pistons takes place

2008 – 2009

  • Locomotive cylinders, rods, and pistons are fully installed
  • Cylinder heads are installed


  • Old cam shafts are removed and new cam shafts are installed
  • Coolant piping is cleaned and reinstalled
  • Oil lubrication piping is cleaned and reinstalled
  • Batteries are installed


  • Engine valve gear is assembled on the engine block
  • Fuel lines are cleaned and installed, or replaced
  • Generator brushes are replaced and commutator is cleaned
  • Fuel Pump and fuel subsystem is plumbed
  • Governor is installed
  • Water leakage test is performed
  • Fuel leakage test is performed
  • Reverser is cleaned and pneumatic hose replaced

December 31, 2011 – Locomotive is Fired


  • Air Compressor is removed from storage, disassembled, and cleaned
  • Air Compressor is rebuilt and repainted
  • Locomotive is placed in locomotive and aligned to crankshaft
  • Generator cooling fan assembly is rebuilt and repainted


  • Compressor is attached to crankshaft
  • Compressor plumbing to air system is attached
  • Compressor accessories are installed
  • Main Generator is cleaned and repainted
  • Cab work begins and floor is replaced
  • Air brake controls are cleaned and replaced
  • Brake cylinders are cleaned, rebuilt, and replaced

Further Updates to Come


To inquire about volunteering on the Locomotive 72 project and other shop activities, please email or call our office at (317) 773 – 6000.


If you wish to contribute to the 72 project, please visit our secure, online donation portal here.