The origins of this loco are a little obscure, it was built in 1932, possibly at the instigation of Haslam & Newton of Deby who supplied the hydrostatic transmission (and offered to maintain it). In this system the engine drove a hydraulic pump and a hydraulic motor drove the wheels, there was no torque converter. It would appear the the accountants agreed to this with the proviso that an existing old loco could be rebuilt to take it, coupled to a 400hp Paxman diesel engine.
As s result of this the loco was nominally a rebuild of a Midland 1F 0-6-0T and kept its running number 1831. As far as i can make out all that was used amounted to the frames (albeit cut and lengthened to make room for the transmission), two of the wheelesets, sandboxes and brakes, everything else was new.
1831 did appear to work although it was never allowed to stray far from Derby works. It is known to have worked at Chaddesdon Sidings, Derby Carriage Works, Toton Yard and Derby Loco Shed at least.
Eventually the transmission failed and 1831 was converted in 1940 to a mobile power unit, in which form it survived until 1955. Other than this conversion there were few modifications made to 1831, the most notable being the small windows at the corner of the cab, which were not present when first built (and later blanked off for the MPU), the livery was always plain black. At some point in its career an additional radiator was fitted in the gap, between the water cooling group and the transmission oil cooler - presumably this was another oil cooler but this is not certain.
Complete Kit Includes: Wheels, Gearsets, Motor & Buffers