The company notionally had 21 Y class locomotives, although three were never operated and only a maximum of 17 were owned at any one time. Their road numbers were recycled.[1][2][3]
In 1887, having commenced operations with hired South Australian Railways Y class locomotives, the company ordered four locomotives of the same design from Beyer, Peacock. They were assembled in Gawler, South Australia by James Martin's Phoenix Foundry. Since the company had an option to sell to the South Australian Railways any that it deemed surplus, two of the locomotives ("1st Y3" and "1st Y4") passed without use. Of the other two, which were 2-6-2T (side tank) locomotives but otherwise the same as the 2-6-0 locomotives, one was sold within a few months; the other was given away as compensation for a collision 11 years later.[4]
Westinghouseair brakes were fitted to Y13, Y15 and Y16 from new and Y1 and Y11 were retrofitted. Y1, Y6, Y8 and Y11 to Y17, which originally had a boiler pressure of 145 pounds per square inch (1000 kilopascals; 10.2 kilograms-force per square centimetre), were rebuilt with 180 pounds per square inch (1200 kilopascals; 13 kilograms-force per square centimetre) boilers and lead adhesion slabs were added to the running boards. Three were superheated between 1924 and 1926.[1]
The locomotives were superseded on main line duties by the A class from 1912 onwards, but many were retained for shunting and secondary duties around the Broken Hill yards and mine sidings. The last was withdrawn in 1961.[1][3]
Semi bogie tender. Sold to South Australian Railways without use 7 November 1888 as Y91
Y4 (2nd)
2-6-0
Beyer, Peacock & Co
3397
1891
1907
Sold to South Mine Broken Hill 1907, later transferred to BHP Whyalla as 3A
Y5 (1st)
2-6-2T
Beyer, Peacock & Co
3170
1890
1898
Forwarded to Sulphide Corporation Central Mine as compensation for one of their locomotives destroyed in a head-on accident with a Silverton locomotive. Transferred to BHP Whyalla as 2A in 1940, withdrawn late 1950s.
Y5 (2nd)
2-6-0
Beyer, Peacock & Co
4391
1901
8 April 1931
Scrapped 1938
Y6 (1st)
2-6-2T
Beyer, Peacock & Co
3357
1891
N/A
Never owned by Silverton: ordered by BHP and landed in Adelaide August 1891 but too heavy for tracks so entered service with South Australian Railways (SAR) in exchange for V class no. 11. In March 1893, the SAR lent it to STC as Y6. Entered service with BHP Broken Hill September 1893, transferred to BHP Whyalla in 1901 as no. 3, withdrawn 1963 and displayed on Whyalla foreshore, moved to Mount Laura Homestead Museum, Whyalla Norrie in 1983.[6][7]
Y6 (2nd)
2-6-0
Beyer, Peacock & Co
3795
1895
7 October 1960
Scrapped July 1963
Y7
2-6-0
Beyer, Peacock & Co
3515
1892
14 October 1929
Scrapped 1934 or 1937
Y8
2-6-0
Beyer, Peacock & Co
3516
1892
27 May 1960
Scrapped July 1963
Y9
2-6-0
Beyer, Peacock & Co
3533
1893
12 January 1931
Scrapped 1937
Y10
2-6-0
Beyer, Peacock & Co
3534
1893
12 January 1931
Scrapped 1937
Y11
2-6-0
Beyer, Peacock & Co
3535
1893
16 May 1960
Stored at Railway Town, donated to Penrose Park Trust, Silverton September 1965[8]
Y12
2-6-0
Beyer, Peacock & Co
3536
1893
17 July 1961
Withdrawn 1961, steamed in 1964 for Broken Hill Club picnic special, stored Railway Town, donated to the Mile End Railway Museum in 1965; subsequently on display at the National Railway Museum, Port Adelaide.[3][9]