Diesel 5705 is BoCo's brother, who was only mentioned in an annual. In another annual, BoCo claimed to have a twin called "CoBo" in order to play a trick on Bill and Ben. Diesel 5705 is in fact a real diesel engine preserved and under restoration at the East Lancashire Railway. During Days Out with Thomas events, Diesel 5705 is given a face to resemble BoCo.


Diesel 5705 survived by historical accident as a technical services engine and then carriage heating unit TDB968006 before being preserved in 1980. The Class 15 Preservation Society has signed an agreement with the owners of Diesel 5705 to become its custodians during its restoration and operation for the next decade, although funding will remain separate.

Technical Details


Diesel 5705 is painted in BR Brunswick green with yellow warning panels.


Companion volumes

Annual Stories



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