• Number: D2, originally D5702
  • Class: BR Class 28
  • Designer: Metropolitan Vickers
  • Builder: Bowesfield Works
  • Configuration: Co-Bo
  • Arrived on Sodor: 1965

BoCo is a Co-Bo diesel who works mainly on Edward's Branch Line. He is painted in the green livery used by British Railways in the 1960s. He first appeared in the book Main Line Engines. He was built in 1958 and arrived on Sodor in 1965.


Main Line Engines Edit

BoCo once accidentally took Bill and Ben's china clay trucks. They decided to play a trick on him, playing on their identical looks to make the Diesel think that one engine was disappearing and reappearing around him. Edward was nearby to sort out the confusion, and Bill and Ben soon came to respect BoCo.

Duck, who was suspicious of diesels due to his own experience, nevertheless took quickly to BoCo when the diesel took trucks to Tidmouth. The two started talking in the shed, but were interrupted when James arrived and called BoCo a "buzzbox". Ironically, James was attacked by a swarm of bees the next day, and so BoCo had to take the Express. Gordon was furious that a mere branch line Diesel got to pull a mainline train. Gordon was later stranded on Edward's branch line due to a signalman's error. Bill and Ben were quick to tease Gordon, and jokingly threatened to haul him away as scrap. When BoCo arrived with some trucks, he sent Bill and Ben to work, and the relieved Gordon felt he owed his life to BoCo.

When Edward had trouble pulling an enthusiasts' train, BoCo helped Duck to shut the big engines up, who said Edward should be preserved. BoCo later filled in on the branchline while Edward was at the Works. Donald and Douglas were the last engines to accept him.

James and the Diesel Engines Edit

BoCo showed Old Stuck-Up around, but abandoned him when the new diesel insulted Sir Topham Hatt for keeping steam engines in service. Things had been smoothed over between James and BoCo by this time.

Gordon The High-Speed Engine Edit

BoCo tried to cheer Gordon up when he got into trouble for spraying ashes onto a wedding party and later helped Gordon to Barrow when his firebars collapsed.

Thomas and the Fat Controller's Engines Edit

BoCo also helped Edward to the Works when his bogie wheel snapped off, and ran the branchline while Edward was undergoing an overhaul.

Thomas and Victoria Edit

BoCo met Victoria when Edward stopped at Wellsworth with her and later.

Thomas and his Friends Edit

BoCo also laughed at Donald after his accident with a set of buffers.


Although BoCo came across as bullying at first, he was still new to Sodor and turned out to be a good sort who was easy-going and good-natured. He also has a genuine good sense of humour.


BoCo is a British Rail Class 28/Metropolitan-Vickers Type 2 diesel-electric locomotive, named after its unusual Co-Bo wheel arrangement. The bogie beneath the power plant carries three powered axles ('Co') and the other carries two ('Bo'). This arrangement was designed to maximise the routes over which the engine could work. Another unusual feature of the Metrovick Co-Bo is the use of a two-stroke diesel power plant rather than the more standard four-stroke. They suffered from mechanical unreliability which, according to Christopher Awdry, the Fat Controller managed to cure in BoCo's case.

Twenty of these engines were built by Metropolitan-Vickers in 1958 as part of British Railways' Modernisation Plan. One 'Metrovick' (D5705) has survived and is preserved at the East Lancashire Railway in Bury.


Railway SeriesEdit

  • Main Line Engines
  • James and the Diesel Engines 
  • Gordon the High-Speed Engine
  • Thomas and the Fat Controller's Engines (does not speak)
  • Thomas and Victoria (mentioned)
  • Thomas and his Friends (cameo)


  • It should be noted that BoCo's name is always spelt with a capital B and a capital C. The name, obviously, is derived from the fact that he is a Co-Bo diesel. Rev. W. Awdry decided that "BoCo" flowed better than "CoBo", and sounded more affectionate.
  • In the Railway Series, BoCo carries his North Western Railway number 'D2', whereas in the television series he carries the number D5702, which is in the range of numbers assigned to the real "Metrovick" locomotives by British Railways. In reality, D5702, built in October 1958, was withdrawn in September 1968 and cut up in November 1969.

Note: This is one of the few articles that uses info from the TV show.