The Works Diesel rescued James after his injector failed, and managed to eradicate James' dislike of diesels with his charismatic persona. He/she then brought the Christmas tree for Thomas from the Other Railway. In Gordon the High-Speed Engine, Donald mentions that there are other diesels at the works. The Works Diesel was later seen talking to Gordon at Barrow-in-Furness.
Although the Works Diesel has not spoken, he/she is described as being friendly and is impossible to not like - even James, who retained a hearty dislike of diesels, could not help but befriend him before the two had even reached the Works.
The Works Diesel is based on a BR Class 47 "Brush" Co-Co.
The Works Diesel is painted in a British Rail "Rail Blue" livery with yellow warning panels.
- Really Useful Engines (possible mention)
- James and the Diesel Engines (does not speak)
- Gordon the High-Speed Engine (mentioned)
- Henry and the Express (cameo)
- Thomas and the Missing Christmas Tree (does not speak)