It is clearly not true that a "replacement part had brought from Crewe" - the train was at Doncaster for less than 2 hours - which is less than the time it takes to get there from Crewe. The part clearly wasn't fitted at any other stage of the journey, either.The train was stopped for the whole time in the platform at Doncaster. We were told that the power car had hit something on the track and that a replacement part had been brought from Crewe. At one point, the plan was take the train to Carlisle and swop the power car but that was abandoned in favour of the repair.
It is clearly not true that a "replacement part had brought from Crewe" - the train was at Doncaster for less than 2 hours - which is less than the time it takes to get there from Crewe. The part clearly wasn't fitted at any other stage of the journey, either.
Pretty good going considering it got to Fort William less then an hour late after being 2 hours late around Doncaster!