This large loco was classified as a 48DLZ by the manufacturer, the Z indicating that it was fitted with an extended frame and air braking. It is also fitted with flameproofing equipment. This allowed diesel locomotives to work safely underground in coal mines without risk of causing explosions (by igniting gases which are so prevalent in such mines) or poisoning the men working in the area.
The loco was supplied new in 1949, as a 2’2” gauge loco, to the Morrison Busty colliery, Annfield Plain; this was a pit in the North Durham area, and was part of a huge colliery modernisation programme then underway under the auspices of the newly formed National Coal Board (N.C.B.). Morrison Busty closed on 5/10/1973, and in January 1974 the loco was moved to the Mabton Engine Works (one of the N.C.B.’s large engineering facilities in the north east) where it was converted to 2’6” gauge. This work was completed by May 1974, and the loco moved to Westoe colliery, near South Shields. In May 1983, the loco moved to Ashington Central Workshops, and returned to Westoe in July 1986. November 1987 saw a return to Ashington National Workshops.
In 1988, the loco was preserved at the Woodhorn Colliery Museum in Ashington. Whilst here, it was re-gauged (for a third time!) to 2’0” for proposed use on a passenger railway at the museum. Changes at the Woodhorn Museum led to the locomotive being donated to the MRT. It arrived at Apedale on 2/3/2006.