Somehow I find it hard to believe that a 70 year old diesel engine from a ship that was built to the standards of a Cavalier could be described as efficient.

These massive machines stood twenty feet tall and weighed over 130 tons. Moving them by rail in one piece to shipyards hundreds of miles away and then installing them in Liberty Ships under construction was not easy. Nevertheless, this task was successfully repeated many times over.But that was not the end of the difficulties associated with these complicated beasts. Operating and maintaining them required experience that was in short supply in the 1940s. Keeping them properly aligned and well oiled was an ongoing task that required not only skill, but considerable dexterity. The engines' multiple and rapidly moving parts could easily snag an unwary engineer's clothing and result in injury.
http://www.jajones.com/pdf/Liberty_Ships_of_WWII.pdf
http://en.wikipedia.org/wiki/Liberty_ship
http://www.lanevictory.org/index.php