GWR Steam Motor

steam motor 93

Power Classification 
CompanyGreat Western Railway
Weight45t 11cwt
Driving Wheels4ft 0ins
Boiler Pressure160psi
Tractive Effort6,530lbf
Valve GearWalschaerts

In the first years of the twentieth century, railway managements turned their attention to the need to provide better local passenger services and to reduce costs, in the face of increasing demand for convenient travel and the competitive threat posed by urban tramways.

The original strengths of railways—a fixed track, multiple vehicle passenger trains, highly structured and staffed stations—had limitations in responding to changing needs. The London and South Western Railway had successfully operated a railmotor, consisting of a self-contained passenger vehicle with its own steam power unit, on its Southsea Railway, and the Great Westen Railway arranged to borrow one unit for trials on its Golden Valley Line in Gloucestershire. The trial proved successful and a steam rail motor was designed by the Chief Mechanical Engineer Churhward. Two units were manufactured, and they entered service on the same route on 12 October 1903. A further 44 were built during 1904 and 1905 and by the time production finished in 1908 the fleet numbered 99 carriage units. There were 112 power units which could be changed between carriages to suit maintenance needs.

On this rural route with a scattered population along the rail corridor, the new vehicles enabled a more frequent service to be operated at lower cost. Stops were made at new locations, and passengers joined and left the train at cheap and simple ground-level platforms using power operated steps on the vehicles. Six new stopping places were provided between Chalford and Gloucester for this service. The guard issued tickets on the train, avoiding the need for staffing at the halts. The vehicles could be driven from either end, so time was not lost in running round at terminals.

The rail motors were also deployed in cities such as Plymouth, where they operated frequent services calling at new stopping places, competing with the new electric tramway.

The relatively limited accommodation led to problems at busy periods, and driving trailers were constructed with a mechanical facility to control the main unit, so that the train could be driven from the driving trailer, maintaining the avoidance of running round at terminals. However the available power in the small steam engine was a limitation, especially on routes with steep gradients and it is recorded that on the Wrington Vale Light Railway it was frequently necessary for the rail motor to stop on the 1 in 50 gradient to raise enough steam to continue.

Steam engines need frequent servicing, and while this was being undertaken the coach unit was not available for use; steam engine maintenance is also exceptionally dirty, and keeping the passenger sections in an acceptable state of cleanliness was an issue.

Most rail motors were converted into driving trailers for push-and-pull trains (sometimes referred to as autocoaches) serving a separate steam locomotive, and the original power units were scrapped. Autotrains offered many of the benefits of rail motors but, because they were operated by separate locomotives, were much more flexible in operation and easier to maintain. The first of the original rail motors was withdrawn in 1914 but sixty-five survived until 1922 and the last was withdrawn in 1935.

Rail motors nos 42 and 49, along with ex-Port Talbot Railway no 1 (which had been acquired by the GWR in 1908) were sold to the Port of London Authority.

All of the fleet were built with four-wheel vertical-boiler power units and a four-wheel trailing bogie under the carriage. Driving wheels were from 3 ft 5in to 4 ft (1,041mm to 1,219mm); cylinders were from 9in × 15in to 12in × 16in (229mm × 381mm to 305mm × 406mm).

The first sixteen rail motors did not provide luggage space and were designated “suburban”, but from No. 17 on, a small luggage compartment was added. The later rail motors were designated “branch”.

Most of the rail motors were built at Swindon Railway Works, but 14 (GWR Nos. 15, 16, and 61–72) were built by Kerr Stuart, and 8 (GWR Nos. 73–80) were built by the Gloucester Railway Carriage and Wagon Company. The GRC&W were primarily carriage builders and seem to have contracted out the construction of the engine to another Gloucester firm, Summers and Scott.


This image has an empty alt attribute; its file name is steam-railmotor-93-and-autotrailer-92-at-glyndyfrdwy-on-the-llangollen-railway-april-2013.jpg

In February 1908 a steam rail motor 93 was turned out from Swindon Railway Works. It was initially allocated to Southall shed before seeing service at Bristol, Croes Newydd, Chalford, Gloucester, Stourbridge, Taunton and Yatton.

It was 70 feet long and 9 feet wide. After running 479,006 miles it was withdrawn in November 1934, the power unit removed and the carriage portion converted into an auto trailer. Now renumbered 212, it operated in this form until May 1956. It was then put into use as a “Work Study Coach” and later as a static office in Birmingham.

In 1970 it was sold to the Great Western Society and moved to their base at Didcot Railway Centre but it was not until 1998 that they were able to make a start on returning it to original condition as a steam rail motor. The frame of the new power bogie was erected in November 2000 at the Tyseley Locomotive Works and was then mounted on wheels and fitted with a boiler. In March 2008 the power bogie was put on display at Didcot. In January 2009 it was moved to the Llangollen Railway where the carriage portion (212) was restored and the two portions brought together. Work was completed in March 2011 and 93 returned to public service at Didcot in May later that year. This had been achieved with the aid of Heritage Lottery funds.

In June 2012 93 was approved for main line operation, even though the re-introduction of wooden bodied vehicles had not been allowed for many years, and was subject to restrictions to reduce the possibility of collisions and any subsequent damage. The water capacity being only 450 gallons means that it has to stop to take on water at frequent intervals – the owners like to limit it to 12-15 miles before being topped up. The coal capacity is limited to three- hundredweight and coal can only be put on the fire whilst the vehicle is stationary but fortunately it is very economical in terms of coal consumption.

In 2013 the restoration of auto trailer No. 92 was completed at Llangollen (as part of the same project). The railmotor and trailer ran together for the first time in preservation later in the year. They are now based at the Didcot Railway Centre.

The boiler certificate is valid until February 2021. The major work will be on the bodywork rather than the boiler but work will not start in 2021.

Home BaseCurrent StatusOwner
Didcot Railway CentreOperationalGreat Western Society
Steam Railmotor 93 and Autotrailer 92 at Glyndyfrdwy on the Llangollen Railway – April 2013
Steam Railmotor 93 coal bunker – April 2013
Steam Railmotor 93 cab – April 2013

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