The Hart-Parr 18-36 was the most popular tractor of the Hart-Parr Company of Charles City, Iowa, in the years before the firm disappeared into the Oliver merger. Built from 1926 to 1930, it was rated at 18.10 horsepower on the drawbar and 36.53 horsepower at the belt pulley — the two figures that gave the model its name.
Hart-Parr 18-36 at a glance
| Maker | Hart-Parr Company, Charles City, Iowa |
|---|---|
| Production | 1926–1930 |
| Predecessor | Hart-Parr 16-30 of 1924 |
| Engine | two-cylinder, slow-speed, water-cooled |
| Cooling | unpressurised water system |
| Lubrication | forced feed |
| Final drive | open gears to the rear wheels |
| Drawbar rating | 18.10 hp |
| Belt rating | 36.53 hp |
| Output in 1928 | about 6,000 tractors |
| Fate of the firm | merged into Oliver Farm Equipment Company, 1929 |
There is no separate Wikipedia article on the 18-36; the facts here come from the Hart-Parr section of the English Wikipedia article on the Oliver Farm Equipment Company, with company history from the German article on Hart-Parr.
History of the Hart-Parr 18-36
From the 12-25 to the 18-36
The 18-36 was the last step in a line that began in 1918, when Hart-Parr released the “New Hart Parr” 12-25. That tractor was much smaller than the old prairie machines and formed the basis for all subsequent Hart-Parr tractors. It had a two-cylinder, slow-speed, unpressurised water-cooled engine, forced-feed lubrication and open gears driving the rear wheels.
Nebraska law required tractors sold in the state to be tested at the University of Nebraska, and there the 12-25 was re-rated at 15–30. In 1924 the design was upgraded to become the 16-30, and in 1926 it was upgraded once more to become the 18-36.
The most popular Hart-Parr
Hart-Parr built the 18-36 from 1926 to 1930, and during that period it was the company’s most popular tractor. Its ratings were measured rather than rounded: 18.10 horsepower at the drawbar and 36.53 horsepower at the pulley. The company produced approximately 6,000 tractors in 1928.
On 1 April 1929 Hart-Parr became part of the Oliver Farm Equipment Company, formed by the merger of the Hart-Parr Tractor Company with the Oliver Chilled Plow Works, the American Seeding Machine Company and Nichols and Shepard. The Hart-Parr name was still used for some time afterwards, and the 18-36 stayed in production until 1930 under the new owner.
The company behind it
Charles Walter Hart and Charles H. Parr met as students at the University of Wisconsin–Madison, where they built three working internal combustion engines as a thesis project. After graduating in 1897 they raised $3,000 and formed the Hart-Parr Gasoline Engine Company. In 1900 the business moved from Madison to Charles City, Iowa, and the Hart-Parr Company was organised there on 12 June 1901 with authorised capital of $100,000.
The first tractor, Hart-Parr No. 1, was completed in 1902 and is counted among the first practical tractors. It used an oil-cooled system and was rated at 30 horsepower at the belt and 17 on the drawbar. The word “tractor” itself is credited to W. H. Williams, Hart-Parr’s sales manager, who in 1907 combined “traction” and “power” because “traction engine” was vague and too long for press releases.
Design and features
- Simple two-cylinder engine: a slow-speed, unpressurised water-cooled unit built for farm fuel and farm maintenance.
- Forced-feed lubrication: a step up from the splash lubrication of earlier tractors.
- Open gear final drive: rugged and easy to repair, if noisy and exposed to dust.
- Measured ratings: 18.10 hp on the drawbar and 36.53 hp at the pulley, rather than round publicity figures.
- Proven line: the last and best-developed version of the 1918 12-25 design.
Hart-Parr 18-36 versions
- 12-25 (1918): the “New Hart Parr”, re-rated at 15–30 after the Nebraska test.
- 15-30: the Nebraska rating under which the tractor was sold in that state.
- 16-30 (1924): the first upgrade of the design.
- 18-36 (1926–1930): the final version and the most popular Hart-Parr of the period.
The 18-36 grew out of the same line as the bigger Hart-Parr 30-60 “Old Reliable”, the prairie tractor that made the company’s name. More machines are in the Hart-Parr collection.
Video: 1929 Hart Parr 18-36 in France
Video by rol rom on YouTube.
Sources
- Oliver Farm Equipment Company, English Wikipedia: Hart-Parr history, 12-25 line, 18-36 production and ratings, merger
- Hart-Parr Company, German Wikipedia: founding, merger, range of engine outputs
