Six retired NSWGR locomotives were used to haul construction and supply trains. The NSWGR had six surplus Q class suburban locomotives. These locos were introduced in 1880 as 4-4-0 tank locomotives built by Beyer, Peacock & Co of Manchester, England. In 1910 their side water tanks were removed and a standard six wheel tender was fitted. Before entering service with the Commonwealth all locomotives were fitted with automatic couplers. The locomotives were re-coded as D class.
The locos proved quite unreliable due mainly to their age and the extreme conditions they encountered and when the G class were introduced they were relegated to shunt duties and were mostly withdrawn from service in the 1920’s.
In mid-1914 twelve G Class locomotives were delivered. These latter locos had frequent boiler failures, and as the lengths to the railheads increased, they were worked to their limits. To reduce locomotive down time, intermediate loco depots were established for emergency repair work.
Lack of good quality water that affected locomotive boilers was a problem from the first days of the Trans-Australian Railway.
There is more information regarding steam locomotives in another segment later in the series.
Source: Locomotives and Railcars of the Commonwealth Railways – National Railway Museum