Diesel 40125, nicknamed "Old Stuck-Up" by James, was a diesel engine who once visited the North Western Railway on loan from British Railways.


The Railway Series

BoCo was to show Diesel 40125 around, but when he saw steam engines in the shed he refused to go further and insulted the railway for keeping them in service. An angry BoCo left him outside while he went inside the shed himself, and a furious James nicknamed him "Old Stuck-Up".

The next day, Diesel 40125 was about to leave when he remembered that he needed refuelling. He attempted to use BoCo and Bear's part of the shed to be refuelled and cleaned, but slid on the oily tracks and crashed into the back of the shed. He was sent home in disgrace after being talked to severely by the Fat Controller; BoCo noted that while he could not hear everything, he did not think it sounded particularly polite.


Diesel 40125 is pompous, rude and arrogant like a lot of unfriendly diesels, and believes that steam power is inferior to diesel power.

Technical Details


Diesel 40125 is based on a British Railways (BR) Class 40 1Co-Co1 diesel-electric engine. Two-hundred members of this class were built from 1958 to 1962, and the last was withdrawn in 1985. These engines were given the nickname "Whistlers" because of the strange whistling noise their engines would make. Seven members of this class are preserved at the National Railway Museum including Diesel 200, the first member of the class built. Class 40 and Diesel 782 share the same basis.

Unlike most diesel engines in the Railway Series, Diesel 40125's number was not fictional. The real 40125 was built in December 1960 as Diesel 325 and was the first member of the class built with "split" headcode boxes. It was withdrawn from service in May 1981 and scrapped at Swindon Works in December 1983.


Diesel 40125 is painted in BR Rail Blue with yellow warning panels. His number 40125 is painted on the sides of his cab in white.



  • The events of "Old Stuck-Up" likely took place before the real 40125 was withdrawn from service in May 1981 and scrapped in December 1983.
  • In his introductory story, he is incorrectly seen with two different coats of paint.
  • Unlike most British Railway diesels, he does not have the "BR" Logo on him.


The Railway Series

Main Series


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