Introduction
Bolinder-Munktell BM-20 Agricultural Tractor
Produced between 1944 and 1950 in Eskilstuna, Sweden, the Bolinder-Munktell BM-20 is a standard-tread tractor designed for agricultural operations. It represents a period of robust post-war mechanical engineering, characterized by its reliance on a two-cylinder liquid-cooled engine and a focus on operational durability.
Engine and Performance
The tractor is powered by a two-cylinder, liquid-cooled engine with a 5.3-liter (323.4 cubic inch) displacement. It delivers a rated power of 41 hp (30.6 kW) at 1050 RPM. The engine features a bore and stroke of 150 x 150 mm, an oil capacity of 10.5 liters, and a coolant capacity of 22.1 liters, ensuring stable thermal management during field work.
Transmission and Drive
The BM-20 utilizes a manual gear transmission providing five forward speeds and one reverse gear. This setup allows the operator to select appropriate speeds for various agricultural implements. The tractor is configured with a two-wheel drive system, requiring manual steering input from the open operator station.
Electrical System
Electrical operations are supported by a generator-based charging system. The starting circuit is rated at 24 volts, utilizing an electric starter, while the secondary electrical system operates on a 6-volt configuration supported by four batteries.
Dimensions and Chassis
With a wheelbase of 180 cm and a total length of 325 cm, the tractor maintains a compact footprint. It weighs 2649 kg, providing the necessary mass for traction. The chassis is equipped with 7.50x18 front tires and 13x28 rear agricultural tires, with a front tread width of 133 cm and a rear tread width of 139 cm.
Conclusion
The Bolinder-Munktell BM-20 is a functional, manually operated tractor suited for general agricultural tasks. Its simple mechanical design, combined with a liquid-cooled two-cylinder engine, offers a reliable solution for operators prioritizing mechanical longevity and straightforward maintenance.
Production Information of Bolinder-Munktell, BM-20
- Standard-tread tractor
- Built in Eskilstuna, Sweden
| Manufacturer | Bolinder-Munktell |
|---|
Dimension and Tires Information of Bolinder-Munktell, BM-20
| Front tread | 52.4 inches [133 cm] |
|---|---|
| Wheelbase | 70.9 inches [180 cm] |
| Height (hood) | 55.9 inches [141 cm] |
| Height (steering wheel) | 72.1 inches [183 cm] |
| Length | 128 inches [325 cm] |
| Rear tread | 55.1 inches [139 cm] |
| Weight | 5842 lbs [2649 kg] |
| Width | 69.8 inches [177 cm] |
| Ag front | 7.50x18 |
|---|---|
| Ag rear | 13x28 |
Engine Specifications of Bolinder-Munktell, BM-20
- Liquid-cooled
- Image courtesy of Kamil Szturc
- 2-cylinder
| Oil capacity | 11.1 qts [10.5 L] |
|---|---|
| Displacement | 323.4 ci [5.3 L] |
| Rated RPM | 1050 |
| Bore/Stroke | 5.91x5.91 inches [150 x 150 mm] |
| Coolant capacity | 23.3 qts [22.1 L] |
| Starter volts | 24 |
| Starter | Electric |
| Power | 41 hp [30.6 kW] |
Transmission Information of Bolinder-Munktell, BM-20
Transmission variants 1
| Type | Gear |
|---|---|
| Gears | 5 forward and 1 reverse |
Mechanical Specs of Bolinder-Munktell, BM-20
- Two-wheel drive
- Manual steering
- Open operator station.
Power Information of Bolinder-Munktell, BM-20
| Engine | 41 hp [30.6 kW] |
|---|
Electrical System of Bolinder-Munktell, BM-20
| Charging system | Generator |
|---|---|
| Batteries | 4 |
| Battery volts | 6 |
Where it sits
With 41 HP, the Bolinder-Munktell BM-20 sits between BM-10 (20 HP) and BM-21 (43 HP) in Bolinder-Munktell's range. Its power puts it in the 67th percentile of 1940s models in our database (263 machines).
Frequently asked questions
How much horsepower does the Bolinder-Munktell BM-20 have?
The Bolinder-Munktell BM-20 delivers 41 HP.
What years was the Bolinder-Munktell BM-20 produced?
The Bolinder-Munktell BM-20 was produced in 1944-1950.
What engine does the Bolinder-Munktell BM-20 have?
The Bolinder-Munktell BM-20 is powered by a 2-cylinder engine.
What transmission does the Bolinder-Munktell BM-20 use?
The Bolinder-Munktell BM-20 uses a Gear transmission.
How much does the Bolinder-Munktell BM-20 weigh?
The Bolinder-Munktell BM-20 weighs 5842 lbs [2649 kg].
Is the Bolinder-Munktell BM-20 4WD?
The Bolinder-Munktell BM-20 is available in 2WD.