Allis-Chalmers HD7 Specs ( 1940-1950 )
Overview
The Allis-Chalmers HD7 is an agricultural crawler tractor produced in Springfield, Illinois, between 1940 and 1950 with a total of 1,803 units built. It features a General Motors 3.5L three-cylinder, 2-cycle diesel engine paired with a 4-speed sliding gear transmission. Official testing recorded a maximum drawbar pull of 12,171 lbs and a tested belt output of 68.68 hp.
Ideal Applications
Crawler Track Configuration:
The HD7 is equipped with 16-inch tracks providing 2,144 square inches of ground contact area and a ground pressure of 5.83 psi.
Tested Power and Pull Results:
According to Nebraska Tractor Test 360, the tractor reached a maximum drawbar power of 57.31 hp and used 4.8 gallons of fuel per hour at maximum belt power.
Engine and Fluid Capacities:
The 3-cylinder diesel engine operates at a rated 1500 RPM and is supported by a 31-gallon fuel tank, a 23-quart coolant system, and an 8.5-quart oil capacity.
Production
| Description | Agricultural Crawler tractor / Built in Springfield, Illinois, USA |
|---|---|
| Manufacturer | Allis Chalmers |
| Total built | 1,803 |
Engine
| Engine type | General Motors 3.5L 3-cyl diesel |
|---|---|
| Fuel tank | 31 gal (117.3 L) |
| Air cleaner | oil bath |
| Bore/Stroke | 4.25x5.00 inches (108 x 127 mm) |
| Compression | 16.0:1 |
| Coolant capacity | 23 qts (21.8 L) |
| Description | General Motors 3-71 / blower diesel / 3-cylinder / liquid-cooled 2-cycle vertical I-head |
| Displacement | 213 ci (3.5 L) |
| Rated RPM | 1500 |
| Starter volts | 12 |
| Oil capacity | 8.5 qts (8.0 L) |
| Belt (claimed) | 60 hp (44.7 kW) |
| Belt (tested) | 68.68 hp (51.2 kW) |
| Drawbar (claimed) | 45 hp (33.6 kW) |
| Drawbar (tested) | 57.31 hp (42.7 kW) |
Transmission
| Gears | 4 forward and 1 reverse |
|---|---|
| Oil capacity | 21 qts (19.9 L) |
| Transmission type | 4-speed sliding gear |
| Type | sliding gear |
Mechanical
| Cab | Open operator station. |
|---|---|
| Drive | crawler |
Dimensions & Tires
| Gauge | 52 inches (132 cm) |
|---|---|
| Height | 69 inches (175 cm) |
| Length | 128 inches (325 cm) |
| Operating weight | 14000 lbs (6350 kg) |
| Width | 81 inches (205 cm) |
Allis Chalmers HD7 Tracks
| Area on ground | 2144 in² (1.4 m²) |
|---|---|
| Ground pressure | 5.83 psi (0.4 bar) |
| Length on ground | 67 inches (170 cm) |
| Width | 16 inches (40 cm) |
Dimensions & Tracks
| Description | 16-inch tracks |
|---|---|
| Weight | 14000 lbs (6350 kg) |
HD7 Serial Numbers
| 1940 | 3 |
|---|---|
| 1941 | 503 |
| 1942 | 1137 |
| 1943 | 5403 |
| 1944 | 5753 |
| 1945 | 8949 |
| 1946 | 12091 |
| 1947 | 13078 |
| 1948 | 15122 |
| 1949 | 16752 |
| 1950 | 18086 |
| Description | FAQ: How to read a serial number table. |
| Location: | Serial number stamped on the right-rear of the transmission case or on a plate near the instrument panel. |
Nebraska Tractor Test 360
| Belt fuel use (max) | 4.8 gal/hour (18.2 l/hour) |
|---|---|
| Belt power (max) | 68.68 hp (51.2 kW) |
| Description | Diesel 4-speed crawlerOctober 15 - 21, 1940Link: Nebraska Tractor Test 360 file / Drawbar performance / Gear 1 used for power test. / Gear 1 used for pull test. |
| Max power | 57.31 hp (42.7 kW) |
| Max pull | 12,171 lbs (5520 kg) |
References
| Description | HD-7 2-Cycle Diesel published in 1949, by Allis Chalmers / Operators Manual Model HD 7 Tractor (T-203E) / Build a Better Farm published in 1940, by Allis Chalmers |
|---|