The 1-tonne engine, which likely would have been transported by horse and cart before being assembled at the remote site, was lifted by a truck-mounted crane through the open roof of its housing as Department of Conservation (Doc) staff watched on Thursday afternoon.
Doc ranger Kevin Pearce said the engine, which has not been operated in more than a year, was no longer firmly fixed to its base and its bearings, piston rod and cam bearings likely all needed either replacing or repair.
"If we continued to run it the way it was, we could end up with nothing but a static engine display," he said.
"If we can get it running, we can have more open days for the public. Hopefully, it will run for another hundred years."
Doc visitor assets programme manager Bill Wheeler said engines of all sizes needed to be operated to remain healthy.
"It's important that it runs. It's like a car - if you sit it in the garage for two-three years, all sorts of things can go wrong with it," he said.
The diesel and kerosene engine had run two or three times a year for the public, but had not run for more than a year, and was unlikely to be operational before February, Mr Pearce said.
Oceana Gold and the New Zealand Historic Places Trust should be commended for their support of the restoration, he said.
