Ruston & Hornsby Ltd, of Lincoln, was formed as the result of the merger between Ruston, Proctor & Co. Ltd and Richard Hornsby & Sons Ltd on September 11, 1918 and their first narrow gauge diesel locomotive left the works on September 1, 1931.
In the summer of 1932, production was moved to the larger Boultham Works, where the firm were eventually to become Britain's largest builder of diesel locomotives, with over 6,500 being built by the time production ceased in 1969. Almost as soon as the firm's 44/48HP 0-4-0 locomotives were making an appearance, an upgraded, more powerful 0-4-0 was on the drawing board. Although many of the features of the 44/48HP were retained for the new 80/88HP, such as the chain drive and running gear, a new type of transmission was fitted, along with Westinghouse airbrakes. The new power unit, Ruston's own 4VPB, delivered 80BHP at 1000rpm and was later supplanted by Ruston's improved 4VPH that delivered 88BHP, but it required compressed air to be injected into the cylinders to be able to start.
While running, an air reservoir was kept charged via the braking system, but after standing idle for a period the reservoir depleted and a secondary source was required to recharge the reservoir. This was achieved by fitting a small, secondary 1½HP 'donkey' engine, giving rise to a distinctive raised cover on the right hand side of the engine compartment that differed in size and placement depending on the make of engine used. Two basic weight options were offered for the 80/88HP, of 17 tons and 20 tons, the difference being achieved by attaching weights to the outside frames, as well as to the front and rear buffer beams.
In 1941, Ruston's locomotive classifications were changed, with the 80/88HP becoming 88DS (with the narrow gauge versions being assigned the DSM and DSN suffix, and the broader gauges assigned DSW). Outward appearance changes to the 'standard' locomotives were mainly confined to the cab area, with examples from mid-1947 replacing the open cab with a fully enclosed cab that featured several ad-hoc styles of front window. The final 88DS, 518494, left Boultham Works on 29 November 1967, bringing to an end a production run of 271 locomotives.
Ruston 441934 was built new for Rowntree & Co. Ltd of York, being delivered in April 1960 to join R&H 421419/1958 and 432479/1959 in the confectionery company's fleet of locomotives as No. 3. In 1979, the York factory bought a new 0-6-0 locomotive and No.3 was transferred to Rowntree's Fawdon factory in Newcastle. Rail services at Fawdon came to a halt on 30 January 1987, with No. 3 being handed over to the North York Moors Railway for preservation. After some years being moved about it was purchased in 2013 by two members of the Derwent Valley Light Railway, Glynnis and Tony Frith. 441934 has now been named Ken Cooke, in honour of the former Rowntree's York employee, D-Day veteran and holder of France's highest military honour, the Legion dHonneur.
