Hyde, the CSAR Rack locomotive was to have a bar frame, two cylinders with 18 inches (457 millimetres) bore and 30 inches (762 millimetres) stroke, and was to use the same drive system as the Nederlandsche-Zuid-Afrikaansche Spoorweg-Maatschappij 32 Tonner, CSAR Class G, which had proven satisfactory in rack service.

[1][2][3] The boiler capacity was not increased to compensate for the additional cylinders and, in service, trouble was experienced under working conditions.

Tests showed that the locomotives could not maintain steam and had insufficient adhesive weight to prevent slipping on the steep gradient.

This method of coupling was unavoidable due to the restricted width of only 3 feet 3 inches (991 millimetres) between tyres.

[1][2] The Le Chatelier counter-pressure air brake system made use of the following: To protect the crew from the smoke and gases in the tunnel, the large cab was totally enclosed and had side doors and windows.

Owing to their failure, the old 32 Tonners remained in service until 1908, when a new alignment with easier gradients, including a new tunnel, was constructed and the rack section could be abandoned.

[1][2][3][4] Their failure can be attributed directly to the fact that two additional cylinders were introduced by the builders while the boiler capacity remained the same, which resulted in a locomotive with an inadequate steaming ability.