Can you differentiate between YDM and WDM railway engines ?
YDM :Originally class 'DY', these were among the first MG main-line diesels, and were survivors from the second batch of North British diesel locos supplied in 1955. Some may still have been working into the end of the 1990s [12/99]. They were originally used by WR for goods haulage on lines where water supply for steam locos was problematic. Later transferred to SCR. CLW replaced the engines on these with Maybach engines around 1975 (1974-1976 according to Hughes). WR phased these locos out in the 1990s.
Builders: North British Locomotive
Engine: Paxman V12 RPHXL II, 625/580hp replaced by Mak/CLW L6 6M 282 A(K), 700hp
Transmission: Voith hydraulic with Cardan shaft drive to bogies