| Weight | 47 tons 15cwt |
| Boiler Pressure | 145psi |
| Cylinders | Outside – 14½in x 20in |
| Tractive Effort | 13,289lbf |
The Y class were numerically the largest class of steam locomotive operated by the South Australian Railways (SAR). 129 were built between 1885 and 1898 of which Beyer, Peacock & Co built 50 at Gorton, Manchester. The remainder were built by James Martin & Co of Gawler (77) and the SAR’s Islington Railway Workshops (2).
Between 1904 and 1924, 48 locomotives were fitted with new Belpaire boilers and designated the Yx class.
The locomotives of Y class operated across all of the SAR’s narrow gauge network and were part of what became almost an Australian 3 ft 6 in standard. Locomotives of similar design served in large numbers as the Silverton Tramway Y class, Tasmanian Government Railways C class and Western Australian Government Railways G class, and also in Queensland and on the Emu Bay Railway and North Australia Railway.
Many Y & Yx class locomotives were withdrawn in the 1930’s and 18 passed to Commonwealth Railways as their NFB class. The locomotives were popular with Western Australia timber concerns and some were sold for use on the timber tramways whilst others were sold to railway construction companies. A few were retained by the South Australian Railways for shunting work.
It was withdrawn from service with the SAR and sold in 1928 at which time it was still a class y locomotive and so never ran as Yx86. It was purchased by the Victorian Construction Company for railway building duties on the Oodnadatta to Alice Springs section of the Central Australia Railway.
The locomotive was later sold to the Bunning Bros in 1944 for use at their Western Australian timber operations. Bunnings Bros rebuilt the locomotive to Yx specification in 1958 by replacing the round-top boiler with a larger, higher pitched Belpaire boiler.
The locomotive is now displayed in the Australian Railway Heritage Society Railway Museum at Bassendean as Yx 86.
There are three Y class locomotives built by Beyer Peacock that have been preserved.
- Y71 – Works number 2762
- Y82 – Works number 2909
- Y97 – Works number 3147
There are also Y and Ts locomotives built by James Martin in Australia that have been preserved.
- Y109 – Works number 8
- Yx135 – Works number 37
- Yx141 – Works number 43
- Yx176 – Works number 178
There are three Y class 2-6-0 locomotives built by Beyer Peacock for the Silverton Tramway Preserved
- Y1 – Works number 2971
- Y11 – Works number 3535
- Y12 – Works number 3536
Preserved British Steam Locomotives 