In the years immediately following World War 2 the NSWGR was in desperate need of new and modern motive power. Twenty mainline locomotives were ordered from the Canadian factory of the American locomotive Company ( Alco ). These became the 40 class. Tenders were also called for ten diesel electric shunting locomotives with offers being received from USA, UK, Germany, Japan, France and Austria as well as Australian manufacturers. Probably more for political reasons than common sense a tender was accepted from a consortium of British Thomson-Houston and Metropolitan-Cammell Carriage and Wagon Co. Despite the fact that the quote was not the cheapest and that neither company had any experience in building large diesel electric locomotives.
The resulting locomotive proved to be one of the lesser triumphs of British engineering and a constant thorn in the side of NSWGR maintenance staff until the scrapping of the final units in 1974. Classified 41 class the Bo-Bo loco was fitted with two Paxman diesel engines rated at 500hp each. A rating which was somewhat optimistic. Rumour at the time was that the diesel engines used were war surplus from submarines which actually required a constant flow of cold sea water for cooling purposes. Subsequent events proved this to be somewhat correct.
Problems with the design were immediately apparent and serious enough that 4110 was retained in England at the manufacturers for ‘further testing’. Different radiators were fitted to try to cope with colonial temperatures resulting in the end platforms disappearing to make way for new and larger radiator cores.
The class was also plagued with numerous electrical problems. In 1957 4106 was experimentally modified in this area but on its first test run to Botany it caught fire ( twice ) and was subsequently towed in disgrace to Chullora workshops where it lurked behind the Boiler Shop for many years. It had had a ‘useful’ life of around three years. Two locomotives, 4102 and 4104 had extra ventilation fitted to the roof by fitting what looked like a birdcage above the hood at each end. This is often mistaken as an extra radiator but was in fact an attempt at ventilation. It was no more successful than previous efforts at cooling and was not repeated on other locos.
After initial trials to Broadmeadow and Thirroul and an ill fated attempt for a double header to reach Goulburn on a fast goods the 41 class settled down to a quiet, if not uneventful, life shunting Enfield and Clyde yards and doing suburban trip trains. Regular workings were the employees specials from Chullora workshops usually consisting of a 41 class and eight End Platform Cars. 4107 spent time on overhead wiring trains during the Lithgow electrification where the crisp mountain air must have been to its liking and from 1958 until its closure in 1961 41’s were regular visitors to the Camden line operating coal trains as far as Narellan.
The 41 class struggled on until replaced by 73 class in the early 1970’s. 4102, complete with birdcage, was preserved by the NSW Rail Transport Museum and currently languishes, unloved, in the old roundhouse at Broadmeadow. Never a successful design they were, however, an important part of the history of early dieselisation of the NSWGR.