Class 207 3D

The Class 3D (later Class 207) was the most modern diesel electric multiple unit to come out of the BR Eastleigh works in the 1960s [1]. Nineteen three car sets were built for operation on the Oxted Line. Compared to earlier DEMUs the Class 207 had a more rounded front end made from steel reinforced fibreglass [2] in common with contemporary Southern Region EMUs.
Preserved DTS of 1317 at Tunbridge Wells West

Information
Number built: 57 (19 3-car sets)
Built: 1962
Builder: BR Eastleigh
Motor: EE4SRKT Mark 2 diesel
Power: 600 hp (447 kW)
Formation: DMBS (Driving Motor Brake Standard) + TC (Trailer
Composite) + DTS (Driving Trailer Standard)

The Class 207 had few of the teething troubles of earlier DEMUs but dropping passenger numbers meant that some of the routes they were intended for closed down. Some therefore were transferred to other routes in two car formations [3].

Electrification of part of the Oxted Line also saw some withdrawn and others moved to other duties including between Reading and Basingstoke. The final units were withdrawn in 2004. Three complete units have been preserved plus a number of other vehicles.
DMBS of 1317 at Tunbridge Wells West

Close up of the engine compartment

[1] Colin J Marsden, Motive Power Recognition 3: DMUs (Ian Allan, 1982) p. 110
[2] Kevin Robertson & Hugh Abbinnett, Southern Region DEMUs (Ian Allan, 2012) p. 55
[3] Ibid. p. 57