This loco, new on 4/10/1934, spent its working life with the Surrey & Dorking United Brick Company, who owned a number of works in Surrey & Sussex. The loco was despatched to the largest of these, at Warnham, north of Horsham where it was used to haul wagons from the end of a rope haulage system to the quarry face where clay (for brick manufacture) was extracted. The company had works with both 2’0” and 2’6” gauge railways, and a key requirement of the design was that the loco could be easily re-gauged. In 1951, following the arrival of 2 new battery locos, MR5821 was re-gauged to 2’6” gauge and employed elsewhere in the works. In 1965, the 2’6” gauge system closed, and the loco was transferred.
Initially it went to Baxter’s Works, Bexhill (and by 1968 it had been converted to 2’0” gauge again) and then Vann Lane works in Surrey. The loco was sold into preservation for the princely sum of £35, and moved to storage at Alan Keef’s Cote Farm works on 14/8/1973. On 4/8/1975, the loco moved to the Long Eaton Light Railway (aka, the Wilsthorpe Light Railway, see fleet no. 7). After the Long Eaton line closed, the loco moved to the Bala Lake Railway on 6/7/1977. Finally, on 22/3/2002, the loco joined the MRT collection. It is the sole surviving 16/24HP type Motor Rail.