class-25-sulzer

The BR Class 25 was a series of 327 Bo-Bo diesel-electric mixed-traffic locomotives built at British Railways Derby, Darlington, Beyer Peacock, and BR Crewe Works between 1961 and 1967, using an uprated Sulzer 6LDA28-B engine producing 1,250 bhp and representing the definitive development of the Derby-Sulzer mixed-traffic locomotive family that had begun with the Class 24 — see the main BR Class 25 entry for full details. The Class 25 became one of the most numerous and widely-deployed mixed-traffic diesel classes in the BR fleet, working freight, secondary passenger, and engineers' trains across virtually every region for over two decades.

An exceptional fourteen examples are preserved, making the Class 25 one of the best-represented BR diesel classes in the heritage fleet.