The "very rough" 1948 Newman diesel tractor was pulled out from a hedge and totally rebuilt by Gordon Handy after countless hours of work and searching for parts.
For the first time it will be displayed with a sister tractor at the two-day Horsepower Rally at Levels International Raceway from Saturday.
Mr Handy said he thought the Newman was too far gone, but restored it anyway.
"After continually looking out my window and seeing this very rare tractor rusting away, I thought I should try and free the seized engine and determine how sad it was and whether I could make it run again.
"To my total surprise after a few hours I managed to get the engine turning over.
The Pleasant Point tractor collector said hours were spent on the internet sourcing parts.
"I managed to find new front rims in the United States, fuel filters in England, a decompression cable in Auckland and many parts locally.
"The WD2 [water cooled diesel] Newman went off to the sandblaster who repaired the guards and bonnet and repainted the tractor.
"I’d hate to add up the hours or the dollars spent, but I now have a very tidy Newman diesel tractor."
Mr Handy found the Newman WD2 at a nearby farm with a tree growing in the middle of it next to a since-restored 1948 Newman AN4 and 1948 small three-wheeler Gunsmith garden tractor.
The die-hard John Deere enthusiast was intrigued by the unusual trio and saw their potential despite perished tyres, seized engines and rusted-out frames caked with decades of dust and chicken litter.
Then he tackled the hardest project.
The light row-crop WD2 and AN4 were made by Newman Industries in Lincolnshire, England.
Both have Coventry Victory engines with the WD2 powered by a single cylinder diesel and the AN4 a petrol-driven two cylinder, air-cooled with a fan on the flywheel.
The diesel option can be found in canal boats in England.
At least one of them is believed to have been used for mowing grass strips on roadsides by the Ministry of Works.
At the time of their manufacture, the British government was encouraging companies to switch from making guns and ammunition to producing tractors for small holdings so they could grow more food.
Mr Handy’s first thought was to give the yellow Gunsmith priority as he could imagine children driving it at a rally and was told it was going before being half-parked in a shed.
The Gunsmith with a five horsepower, single-cylinder JAP engine has a two-speed gearbox powered by a belt, with an idler pulley acting as a clutch when the tension is released.
He grew up on a mixed farm in the back of Timaru and served his time as an apprentice mechanic.
The retired John Deere dealership owner, who once had six branches throughout the South Island, has a long affinity with farm machinery.
He owns his grandfather’s first tractor — a 1937 JD A row-crop General Purpose model — and his 1948 JD AW with a wide axle, as well as his his father’s 1948 big two-cylinder JD G model.