Class 108 DMU Modifications

Modifications

Here are details of some of the many modifications made to the class.

Window bars

Sets at certain depots received window bars over the passenger door droplights and had stops to limit the operation of the sliding lights. There were because the sets worked over routes with restricted clearances. South Gosford was one, Carlisle another (for Whitehaven Tunnel), these sets were then transferred to Heaton.

The image shows the window bars fitted to a passenger door on DMBS M50967 during 1970.

Oval Buffers

The buffers fitted to the class were pretty standard as being small round buffers. However at least two vehicles - 50608 and 50626 - have been noted with oval buffers (on the cab end, inner end unknown). The latter is pictured with them in the 1969 Ian Allan DMU ABC while in green livery with small yellow panel. It still had these in 1972. By 1980 it had regular small round buffers.

Underframe Strengthening

Ron Stringer worked at Derby C&W from 1963 to 1980, and notes^[1]: "Another modification that applied to the 108s was replacement of the inner frame longitudinals that had fractured around the engine mountings. these were replaced with steel frames. There was also fractures of crossmembers in the vicinity of the engine oil filler."

Auto-Gear

51937 at Chester on 8/7/90 as part of set CH619. Ian McDonald.

Two power cars — Heaton based 53954 and Chester based 51937 — were experimentally fitted with automatic geaboxes in 1990. To make it easily identifyable to staff, they (and 53954's partner DTSL 54265) carried 'AUTO-GEAR' on the front under the left cab window.

The conversion work for 51937 was done in early 1990 at the Derby Engineering Development Unit, then moving to BRML Doncaster by February 18 for overhaul.^[2] Heaton based driving trailer 54263 was noted as being a partner for Chester's 51937^[3] but this never left Heaton. On May 12th 51937 (still carrying its former Tyseley set number T211) was noted running between Coventry and Nottingham partnered with Class 104 DMSL 53494.^[4]

53954 at Lancaster, date unknown. Alex Drennan

53954 seemed to mainly working in the Carlisle area. On this vehicle the gear seems to have remained fitted until withdrawal, it was withdrawn from Heaton in late July 1991.

51937 was transferred from Chester to Tyseley in September 1990 then to Longsight in July 1991. By July 1992 the "AUTO-GEAR" text was no longer on the cab front suggesting the equipment have been removed from this vehicle. It would be transferred to several other depots before being becoming a sandite/route learner.

LMR Traction Bulletins

These details are from a series of booklets issued to staff by the London Midland Region as Traction Bulletins to notify them of changes.

Issue 34 - September 1982

Issue 38 - March 1984

Issue 39 - August 1984

Seats

On withdrawal 53930 was noted as having Cravens style passenger seats - seen through the windows of the vehicle in the image. When or why this was done is unknown, also unknown is whether any other vehicles received them.

Asbestos

It seems the first twelve sets delivered — NER twins (E50599/56190 - E50610/56201) — were built with blue asbestos in the floor, walls, ends and ceiling. The remainder would have glass fibre insulation.

Below are pages from a vehicle log kept by the RTC at Derby dated circa 1984 which included the asbestos status for each vehicle, showing that the blue asbestos had been removed or partly removed from some of the first sets. The codes for the asbestos columns are: / not built with blue asbestos; B - blue asbestos; and C - removed. In the remarks column OV means open van (no cage).