the branch line was dieselised in 1966, with a special nzrls excursion train on 12 march 1966 to mark the change, hauled by two b class steam locos. passenger trains, mainly for miners, ran to 23 june 1972, apart from a special train for railway enthusiasts on 16 december 1972 hauled by a d class diesel loco. a 1935 schedule allowed 45 minutes for the all stations trip from huntly to glen afton. the rotowaro to glen afton section west of rotowaro was closed from 5 march 1973, as the mines had run out of coal. the line was shortened from 14.10 km to 7.97 km.