10 H.P.

10 H.P. loco on test at a sand quarry in the Leighton Buzzard area.

This was the smallest type of loco ever produced by Motor Rail and was, according to the May 1963 edition of The Contract Journal, "specially developed for use in tunnels and mine galleries and for applications where axle loading must be kept to a minimum." At Bedford, it was affectionately known as the "Mini Simplex" or "Duplex."

The power unit of these locos was the Lister SL2 (and later SR2) air-cooled diesel engine, which produced 10 H.P. at 2000 R.P.M. and this was coupled to an epicyclic gearbox by means of vee belts. This gearbox gave one speed in either direction with the forward/reverse and neutral being operated by hydraulically activated cone clutches. The brake was cable operated to an expanding drum fitted on the final drive shaft of the gearbox. The wheels and axleboxes were supplied by Allens of Tipton, a firm better known for making wagons.

Haulage capacity of these locos, that only weighed in at 1-Tons, was given as 27-Tons on the level, going down to just 2.3-Tons on a gradient of 1 in 15.

Optional extras that could be supplied were: electric start, electric lighting (with or without battery), cab or canopy, exhaust conditioner (naked flame mines only). The type designation was later changed to 12 H.P. and with the introduction of the SR engine it was renamed 15 H.P.

Number Series (built between 1963 and 1968)

26001-26007 (10 H.P.), 26008-26016 (12 H.P.), 26017-26022 (15 H.P.).

A 10 H.P. dwarfed by its load of sand filled V-skips.

Another in the works at Bedford.