Allis Chalmers HD21
Power
225 hp
Production
1954-1965
Engine
Supercharged diesel, 6-cylinder
Transmission
Torque converter
Introduction
Allis-Chalmers HD21 Crawler Tractor
The Allis-Chalmers HD21 is a heavy-duty agricultural crawler tractor produced in Springfield, Illinois, USA, between 1954 and 1965. Designed for demanding field operations, this model is characterized by its significant mass and high-torque drivetrain.
Engine and Performance
The tractor is powered by a 6-cylinder, liquid-cooled, supercharged diesel engine with a displacement of 844 cubic inches (13.8 L). With a bore and stroke of 133 x 165 mm and a compression ratio of 13.3:1, the engine delivers 225 horsepower at a rated speed of 1800 RPM. An oil bath air cleaner is integrated to ensure engine longevity in dusty agricultural environments, and the cooling system has a capacity of 75.7 liters.
Transmission and Drivetrain
The HD21 utilizes a torque converter transmission, which provides smooth power delivery under load. The drivetrain offers two forward gears and one reverse gear, allowing for controlled maneuverability. The machine operates on a crawler track system, which provides the necessary traction for heavy-duty pulling and working on challenging terrain.
Mechanical and Physical Specifications
The tractor features an open operator station with contracting band brakes for stopping and steering control. With an operational weight of 45,500 lbs (20,638 kg), the machine is engineered for stability and high drawbar pull capabilities. The electrical system is supported by a 24-volt starter.
Conclusion
The Allis-Chalmers HD21 is a specialized agricultural crawler tractor designed for heavy-duty traction tasks. Its combination of a high-displacement engine, torque converter transmission, and substantial track-based weight makes it suitable for intensive fieldwork and land preparation where high power and stability are required.
Production Information of Allis Chalmers, HD21
- Agricultural Crawler tractor
- Built in Springfield, Illinois, USA
| Manufacturer | Allis Chalmers |
|---|
Engine Specifications of Allis Chalmers, HD21
- Allis-Chalmers
- Liquid-cooled vertical I-head
- Supercharged diesel
- 6-cylinder
| Starter volts | 24 |
|---|---|
| Displacement | 844 ci [13.8 L] |
| Air cleaner | Oil bath |
| Bore/Stroke | 5.25x6.50 inches [133 x 165 mm] |
| Coolant capacity | 80 qts [75.7 L] |
| Rated RPM | 1800 |
| Compression | 13.3:1 |
| Power | 225 hp [167.8 kW] |
Transmission Information of Allis Chalmers, HD21
Transmission variants 1
| Type | Torque converter |
|---|---|
| Gears | 2 forward and 1 reverse |
Mechanical Specs of Allis Chalmers, HD21
- Contracting band brakes
- Open operator station.
| Drive | Crawler |
|---|
Power Information of Allis Chalmers, HD21
- Https://www.tractordata.com/farm-tractors/003/0/8/3083-allis-chalmers-hd21-tests.html
Where it sits
With 225 HP, the Allis Chalmers HD21 sits between 4W-220 (220 HP) and 8550 (300 HP) in Allis Chalmers's range. Its power puts it in the 99th percentile of 1950s models in our database (592 machines).
Frequently asked questions
How much horsepower does the Allis Chalmers HD21 have?
The Allis Chalmers HD21 delivers 225 HP.
What years was the Allis Chalmers HD21 produced?
The Allis Chalmers HD21 was produced in 1954-1965.
What engine does the Allis Chalmers HD21 have?
The Allis Chalmers HD21 is powered by a Supercharged diesel, 6-cylinder engine.
What transmission does the Allis Chalmers HD21 use?
The Allis Chalmers HD21 uses a Torque converter transmission.