| Manufacturer |
Hart-Parr |
| Price |
1,195(USD) |
| Model |
20 |
| Equipment Type |
Standard-Tread Tractors |
| Factory |
Charles City, Iowa, USA |
NEBRASKA TRACTOR TEST 79
| Description |
Kerosene 2-speed 2WD/June 11 - 17, 1921/Link: Nebraska Tractor Test 79 file/Drawbar performance |
| Belt power (max) |
23.01 hp/17.2 kW |
| Max power |
14.08 hp/10.5 kW |
| Max pull |
2500 lbs/1134 kg |
HART-PARR 20 POWER
| Drawbar (claimed) |
10 hp/7.5 kW |
| Belt (claimed) |
20 hp/14.9 kW |
| Drawbar (tested) |
14.08 hp/10.5 kW |
| Belt (tested) |
23.01 hp/17.2 kW |
ENGINES OVERVIEW
The Hart-Parr 20 tractor features an engine option of either a 4.6L or 5.1L 2-cylinder gasoline configuration, providing robust power for agricultural tasks. The advantages of this tractor include its reliability and simplicity in design, making it suitable for routine farming operations, but its relatively low horsepower compared to modern alternatives could limit performance in heavier applications. Operators should consider the fuel efficiency and maintenance requirements, which can vary between the smaller and larger engine options.
| Description |
Hart-Parr 4.6L 2-cyl gasoline/Hart-Parr 5.1L 2-cyl |
ENGINE DETAIL 1
The Hart-Parr 20 tractor, with a 281.4 cubic inch (4.6 L) displacement and a bore/stroke ratio of 5.25x6.50 inches, is engineered for low-end torque, making it suitable for heavy-duty agricultural applications. Operating at a rated RPM of 800, its dual-cylinder, liquid-cooled engine ensures consistent performance in demanding conditions, though it may face challenges in high-speed operations due to its low RPM design. Overall, it excels in durability and reliability for farming tasks but may not be ideal for applications requiring rapid maneuverability or higher speeds.
| Description |
Hart-Parr/gasoline/2-cylinder/liquid-cooled |
| Displacement |
281.4 ci/4.6 L |
| Bore/Stroke |
5.25x6.50 inches/133 x 165 mm |
| Rated RPM |
800 |
ENGINE DETAIL 2
The Hart-Parr 20 tractor features a robust 309 cubic inch (5.1 L) liquid-cooled, 2-cylinder engine, providing a balance of power and thermal efficiency. With a bore and stroke of 5.50 x 6.50 inches (140 x 165 mm), it is well-suited for heavy agricultural tasks, but may face limitations in fuel efficiency and torque at lower RPMs. The introduction of the larger engine in the model 20C post serial number 35501 enhances performance, making it more favorable for demanding field work scenarios.
| Description |
Hart-Parr/2-cylinder/liquid-cooled/The larger engine was used in the model 20C beginning at tractor serial number 35501. |
| Displacement |
309 ci/5.1 L |
| Bore/Stroke |
5.50x6.50 inches/140 x 165 mm |
HART-PARR 20 ENGINES
The Hart-Parr 20 tractor features an engine option of either a 4.6L or 5.1L 2-cylinder gasoline configuration, providing flexibility in power output based on operational needs. The 5.1L variant offers enhanced torque, ideal for heavier towing tasks, while the 4.6L may provide better fuel efficiency for lighter duties. It's advisable to consider the intended use—agricultural, industrial, or collector's—when choosing between the engine options, as maintenance and parts availability can vary significantly with age and usage.
| Description |
Hart-Parr 4.6L 2-cyl gasoline/Hart-Parr 5.1L 2-cyl |
TRANSMISSION
The Hart-Parr 20 tractor features a simple two-speed gear system with one reverse, which can limit operational versatility in certain tasks. This setup is advantageous for straightforward agricultural applications but may present challenges in scenarios requiring frequent speed adjustments or maneuverability. For optimal performance, users should consider the intended tasks, as the limited gearing may not suit complex or varied field conditions.
| Type |
gear |
| Gears |
2 forward and 1 reverse |
MECHANICAL
The Hart-Parr 20 features a 4x2 2WD chassis, providing basic maneuverability for agricultural tasks, but may struggle in uneven or wet terrains compared to 4WD models. Its bull gear final drives offer high torque and durability, ideal for plowing and heavy-duty applications, though the manual steering can lead to operator fatigue over extended use. With a 2-speed gear transmission, it allows for versatility in speed; however, the open operator station may expose the driver to elements, impacting comfort during prolonged operation.
| Chassis |
4x2 2WD |
| Final drives |
bull gear |
| Steering |
manual |
| Cab |
Open operator station. |
| Transmission |
2-speed gear |
HART-PARR 20 TIRES
The Hart-Parr 20 tractor features a robust ag front tire size of 28x5 inches and an expansive ag rear size of 46x10 inches, which enhances traction and stability on uneven terrain. The steel wheels provide durability for heavy-duty applications, but they may lead to increased weight and limited flotation in soft soils. Ideal for heavy towing and fieldwork, this tractor excels in agricultural scenarios requiring power and steadfastness, albeit with the challenge of operator comfort due to minimal cushioning.
| Ag front |
28x5 steel |
| Ag rear |
46x10 steel |
DIMENSIONS
DIMENSIONS & TIRES
The Hart-Parr 20 tractor, weighing 4440 lbs (2013 kg), features large rear tires (46x10) that provide enhanced traction and stability for heavy-duty field operations, making it suitable for plowing and tilling. The front tires (28x5) are narrower, which may result in a limited load-bearing capacity and stability during heavy turns or uneven terrain. A potential challenge is the tractor's overall weight distribution; proper ballast might be necessary to optimize performance in various agricultural applications.
| Weight |
4440 lbs/2013 kg |
| Front tire |
28x5 |
| Rear tire |
46x10 |
20 SERIAL NUMBERS
| 1920 |
35001 |
| 1921 |
35025 |
| 1922 |
35501 (20C) |
| 1923 |
35522 (20C) |
| 1924 |
35750 (20C) |
