The NZASM 14 Tonner 0-4-0T of 1889 was a South African steam locomotive from the pre-Union era in Transvaal.

In 1889, the Nederlandsche-Zuid-Afrikaansche Spoorweg-Maatschappij acquired its first locomotives for use on the new railway which was being constructed from Johannesburg to Boksburg.

[1][2] As a result of the rapid development of the goldfields on the Witwatersrand in the 1880s and the demand for coal by the growing industry, the Volksraad of the Zuid-Afrikaansche Republiek (ZAR), also known as the Transvaal Republic, granted a concession to the Nederlandsche-Zuid-Afrikaansche Spoorweg­maatschappij (Netherlands-South African Railway Company, NZASM) on 20 July 1888 to construct a 16-mile long (26-kilometre) railway from Johannesburg to Boksburg.

[1][2][3][4] The concession was extended the following year to continue the line eastwards to Springs, where coal was known to exist, and westwards via Roodepoort to Krugersdorp.

The Murdoch's D slide valves, mounted above the cylinders, were arranged at an incline and were actuated by Allan straight link motion.

In this type of valve gear, the valve rod and the expansion link are respectively connected to opposing arms on the reversing shaft, so that partial rotation of the shaft moves the link and the die block in opposite directions.

It hauled the first train on the Randtram line when it was opened on 17 March 1890 and was retired in December 1903, by which time it had covered a distance of 113,309 miles (182,353 kilometres).

[1][3] The NZASM 14 Tonner works numbers, IMR and CSAR renumbering and their disposal are listed in the table.