The Class 31s

These Brush Type 2 diesel-electric locomotives were built at Brush Traction in Loughborough between 1958 and 1962 with the initial order being placed in 1955 as part of the BTCs ‘Pilot Scheme’ / ‘Modernisation Plan’ . A total of 263 of these locomotives were built with the first one being accepted into traffic by BR in September 1957 with the intention of replacing BRs steam traction on the main line.

Originally built containing a Mirrlees JVS12T engine (and designated Class 30s), this proved to be unreliable following inspections at classified overhauls and in 1964 a works programme commenced a three year plan to re-engine the locomotives with the 1470bhp English Electric 12SVT engines and re-designated as the Class 31s under the TOPS re-numbering scheme.

When delivered, the locos were numbered in the 55xx series and painted in the Brusnwick Green livery. Front yellow warning panels came later in the 1960s. After BR corporate Blue livery became the norm, the Class 31s followed suit and have since been painted in all sorts of liveries depending on their workload and operator.

Originally intended for service on the Eastern Region of BR, it was inevitable that the locos gradually became common on both the Western region (following the withdrawal of the diesel-hydraulic traction) and London Midland regions as well during the 1970s and 1980s.

Able to work any trains from the lowly engineers to the high speed express, the 31s became known as one of the more successful BR designs alongside the Class 37s and 47s which are still soldiering on to this day.

Whilst there are but a handful of the Class 31s left on the mainline, no less than thirty three Class 31s have made it into preservation. It is interesting to note that the first (31018 – D5500 as built) and last (31327 – D5822 as built) locomotives are among those saved from the cutter’s torch.

Class 31 Technical details

Built Brush Traction between 1957-1962
Introduced 1957 onwards
Pre-TOPS number scheme D5500 – D5699 and D5800 – D5862
Engine English Electric 12SVT producing 1470bhp
Transmission Diesel-electric
Wheel layout A1A – A1A
Length 56ft 9in (17.3m)
Width 8ft 9in (2.7m)
Height 12ft 7in (3.8m)
Weight 113t in full operational order
Max speed 90mph
Multiple Working Blue Star

5580 (31162) Entering traffic on the 14th January 1960 as 5580, its Mirrlees power unit was swapped for the English Electric design on the 2nd December 1967.

Initially allocated to Norwich depot, the loco was also based at March, Immingham, Finsbury Park, York, Thornaby Healey Mills and Bescot before ending its days back at Immingham.

5580 underwent a general overhaul and conversion to dual-braking (air and vacuum brakes) at Doncaster Works in November 1973 after which it emerged as TOPS numbered 31162. A second general overhaul took place (again at Doncaster) in April 1983.

31162s last passenger working was 2E34, the 15.16 Carlisle to Leeds on the 23rd August 1990.

Withdrawn from BR service on 18th May 1992 having been simply ‘switched off’, 31162 was stored at Immingham TMD pending disposal and was acquired by The A1A Group (as the group was known then) following a successful bid via the tendering process.

In January 1994, the loco was moved to the Midland Railway Centre at Butterley where over the next four years extensive bodywork restoration to near-original condition was undertaken which included both cabs being rebuilt and other original features recreated including body-side footsteps, replica nose-end doors and working head-codes.

After a number of years overhauling 31225s boiler, this was installed in 31162 and passed for use in October 1999 allowing the first Class 31 to steam-heat a train to operate since 1985 (31162’s original boiler being isolated in October 1981). The boiler has operated over the last few years but was recently taken out of service at the end of the 2007 operating season to allow for its planned overhaul.

Now sporting a very smart coat of BR blue paint and numbered as ‘5580’, the 31 will be the first of its type to work on the GWR for almost 10 years and will be the first time in preservation one has visited Cheltenham Racecourse.

The GWR was once host to a resident Class 31, 5541 (31123) which ran for a few years before failing and eventually falling into a state of flux. Following several years of open storage in Toddington’s north headshunt, the loco was eventually sold for scrap… to A1A Locomotives Limited who broke 5541 for spares. Ironically, it is said that some of the components off ‘our’ 31 have been used to repair 5580 so in a way, 5541 is making a return… spooky!

Thanks to Chris Taylor for this picture of D5541.