MR 3835 / LMS Fowler 4F Class steam locomotives – Class Information

No. 43924 at Keighley station on the Keighley & Worth Valley Railway

This week we turn to the Midland 3835 / LMS Fowler 4F Classes, 0-6-0 engines designed for freight work. Once looking at the background of both classes, we will then move onto the preserved members and their current status.

Midland Railway 3835 Class

Credit: Ben Brooksbank

Locomotive policy on the Midland Railway was in favour of smaller engines to haul all trains across the Midland Railway. When the need for a medium-sized freight locomotive arose, Fowler chose the 0-6-0 wheel arrangement for the new class.

Initially, two engines were built and entered service in 1911. These locomotives, No.3835 and 3836, remained the only engines of the class until 1917 when the further locomotives came in batches. The class totaled 197 members by 1922, before grouping into the London Midland Scottish Railway.

The basic dimensions of the class include: 0-6-0 wheel arrangement (coupled wheels – 5ft 3in), G7S boiler pressed at 175 lbf/in2, tow cylinders (two inside) (20in diameter and 26in stroke) worked by Stephenson valve gearing, total weight came in at 48 long tons 15 cwt (engine only) and a tractive effort of 24,555 lbf (MR Power Class 4, LMS/BR 4F).

Production Series

  1. Derby Works (MR) – No.3835 to 3936, 3987 to 4026 (1911 (3835 & 3836), 1917 to 1922)
  2. Armstrong Whitworth – No.3937 to 3986 (1921 to 1922)

Performance in Service

4027 at Rainhill
4027 at Rainhill // Credit: Barry Lewis

After six years of running on their own, 3835 and 3836 were joined by several batches of engines right up until grouping. The class could be seen across the whole MR infrastructure, usually hauling freight trains of various types. Their light axle loading permitted them to run across branch lines, where in later years they could be seen hauling passenger trains too.

The batch of five engines built by Armstrong Whitworth was originally based on the  Somerset and Dorset Joint Railway, taking the numbers 57 to 61. When transferred to the LMS in 1930 they received the new numbers of 4557–61.

The biggest issue with the class was the axleboxes had a tendency to overheat. This was due to them being short in design, a common practice on the MR.

LMS Fowler 4F Class

LMS 4129
LMS 4129 // Credit: Andy Dingley (scanner) – Original by Allen, Cecil J. (1928)

Grouping of 1922 formed the London Midland and Scottish Railway, which the Midland Railway was absorbed into. Fowler went on to become the new company’s Chief Mechanical Engineer and most of the directors came from the MR. Due to this, the small engine policy of MR days stayed and lead to further 0-6-0 being built.

The new class of 0-6-0 freight engines was called the Fowler 4Fs. These closely followed the design of the 3835 class but with a number of minor improvements. This includes changing the driver’s side from right-hand to left-hand to bring the class in line with new LMS policies. Problems with the axleboxes on the 3835 class was corrected in the Fowler 4Fs by fitting mechanical lubricators, ensuring the axleboxes had sufficient lubrication.

Production Series


  1. Derby Works (LMS) – Lot 7, No.4027 to 4034
  2. Crew Works (LMS) – Lot 10, No.4107
  3. St. Rollex Works (LMS) – Lot 11, No.4177 to 4178


  1. Derby Works (LMS) – Lot  7, No.4035 to 4056
  2. North British Locomotive Company (NBLC) – Lot 8, No.4057 to 4081
  3. Kerr, Stuart and Company Ltd – Lot 9, No.4082 to 4106
  4. Crewe Works (LMS) – Lot 10, No.4108 to 4158
  5. St. Rollex Works (LMS) – Lot 11, No.4179 to 4206
  6. Derby Works (LMS) – Lot 29, No.4207 to 4216


  1. Crewe Works (LMS) – Lot 10, No.4159 to 4176
  2. Derby Works (LMS) – Lot 29, No.4217 to 4287
  3. Crewe Works (LMS) – Lot 28, No.4302 to 4311
  4. Kerr, Stuart and Company Ltd – Lot 31, No.4332 to 4342
  5. Andrew Barclay Sons & Co. – Lot 32, No.4357 to 4361
  6. NBLC – Lot 33, No.4382 to 4399


  1. Derby Works (LMS) – Lot 29, No.4288 to 4301
  2. St. Rollex (LMS) – Lot 30, No.4312 to 4322
  3. Kerr, Stuart and Company Ltd – Lot 31, No.4343 to 4356
  4. Andrew Barclay Sons & Co. – Lot 32, No.4362 to 4381
  5. NBLC – Lot 33, No.4400 to 4406
  6. Derby Works (LMS) – Lot 42, No.4407 to 4436
  7. Crewe Works (LMS) – Lot 43, No.4437 to 4446
  8. NBLC – Lot 46, No.4477 to 4506


  1. St. Rollex Works (LMS) – Lot 30, No.4323 to 4331
  2. Crewe Works (LMS) – Lot 43, No.4447 to 4456
  3. Norwich Works (LMS) – Lot 44, No.4457 to 4466
  4. St.Rollex Works (LMS) – Lot 45, No.4467 to 4476
  5. Crewe Works (LMS) – Lot 56, No.4507 to 4556


  1. Crewe Works (LMS) – Lot 137, No.4562 to 4575


  1. Derby Works (LMS) – Lot 146, No.4577 to 4586
  2. Derby Works (LMS) – Lot 147, No.4587 to 4596


  1. Derby Works (LMS) – Lot 147, No.4597 to 4604


  1. Derby Works (LMS) – Lot 147, No.4605–4606

Performance in Service

The Fowler 4Fs shared the same working careers as the MR 3835 class. With the class being built under LMS ownership, they were designed to run across the whole LMS network, and most likely led to them being spread out further than the MR 3835 class.

Decline and Withdrawal

43931 on freight
Credit: Timeline Events

With the introduction of the BR Standard Classes featuring three power class 4 engines (more information on these can be found here), the withdrawal of the 3835 class started in 1954 when No.43862, at roughly 35 years old, was scrapped. 11 years later, 22 members of the class could still be seen running, but by the early 1960s engines often ran in filthy states. By the end of 1965, the class had all been withdrawn, leaving only one engine left, which started preservation in Barry Scrapyard.

1959 saw the first Fowler 4Fs withdrawn, this being 44 engines. By 1966 only 11 were left in service, all withdrawn by the end of the year. Three engines have survived.


MR 3835 Class

One example has survived into preservation, this being No.(4)3924. Entering Barry in Autumn 1965, 3924 became the first engine to leave the famous South Wales scrapyard three years later in 1968. Arriving at the Keighley and Worth Valley Railway (KWVR) in 1970, the small team who formed The 4F Society to purchase the engine spent four years restoring 3924 back to her former glory.

No. 43924 prepares for departure at Oakworth
No. 43924 prepares for departure at Oakworth

The locomotives first boiler ticket ran out in 1987, leading to 3924 being withdrawn from traffic. In 1990, while as a static display, the KWVR brought the engine from the society. After over two decades out of steam, 43924 returned to steam in 2011 wearing Unlined BR Black with Late Crest.

LMS Fowler 4F class

Three engines of the LMS 0-6-0 freight engines have lived on passing though the phasing out of steam in 1968.

  1. 4027
    Credit: Vale of Berkeley Railway

    (4)4027 – After spending 10 years of being based at various ex-LMS shed across the country, 4027 eventually found a permanent home at the Midland Railway Centre, based at Butterley. 1979 saw the engine back in traffic hauling passenger trains down the Centre’s line. Now under the ownership of the National Railway Museum, 4027 is currently undergoing an overhaul at the Vale of Berkeley Railway.

  2. (4)4123 – The only Crewe built example left, which ended up being brought by Barry Scrapyard in 1965. By the time the engine left in late 1981, many parts and components has either been removed or damaged heavily by the high salt content in the air and weather exposure. Initially based at the Mid Hants Railway, owners the London Midland Society moved their assets to the Avon Valley Railway part way through 4123’s restoration. Here, much progress has been made on restoring 4123. Majority of the work needed is complete but the engine still requires further attention before steaming once again.
  3. (4)4422 – Just over 10 years 4422 spent at Barry before a group called the 44422 Locomotive Company Ltd purchased the locomotive, and a tender from a different site, for operation on the Churnet Valley Railway once restored. Restoration took 15 years, with 4422 back to hauling trains in 1992. On expiry of its boiler ticket, the owners and the West Somerset Railway have made an agreement which will see 4422 based at the line for 25 years, which started late 2014. Returning to service in early 2016, 4422 has suffered from a few issues, the latest being cracks found in all six coupled wheels, which are receiving repair work now.

That’s another Class Information completed, time for the next Sole Survivor in a week’s time. We hope you have enjoyed this week’s Class Information (and new Lost Class series, more information here), stay tuned for next week’s article.


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