Hart Parr was a very early American builder of gas tractors with the Hart Parr 30-60 being one of the more successful “Prairie” style tractors. However by 1919 the Prairie style tractors were obsolete being far too big and clumsy for the average farmer of the time. The need was for a smaller more nimble tractors. Hart Parr’s first attempt to meet the needs of farmers at the time ,the “Little Devil”, was a complete failure and the tractors were recalled. However, the right direction was taken in 1918 with the “New Hart Parr” 12-25 model, which formed the basis for all subsequent Hart-Parr tractors. The “New Hart Parr” was a tractor equipped with a two-cylinder, slow speed, water-cooled engine with force feed lubrication and open gears used to drive the rear wheels. The design after testing in Nebraska was re-rated at 15-30. A smaller model, the 10-20, was added to the range in 1921, and this was soon joined by the big 22-40 in 1923, which featured two 20 hp twin-cylinder engines side by side.
The 10-20 was produced until 1924 when it was replaced by the 12-24.
The Hart Parr 12-24 tractor was a two cylinder tractor with a cylinder bore of 5.5 inches and a stroke of 6.5 inches running at 850 rpm maximum. The tractor was fitted with a transmission offering two speeds ahead and one speed in reverse, a dry clutch, an automotive type coolant radiator which was not pressurized and an air cleaner. The tractor used water as the coolant. Hart Parr built the 12-24 from 1924 to 1930.
The tractor was conventional in construction for the time, with a frame built up of structural steel components, riveted together with the engine, transmission and other components of the tractor then bolted to this frame.
The Museum holds two 12-24s in the collection, SN 40273 and 42669.