Allis-Chalmers Model C Overview
Built from 1940 through 1949, the Allis-Chalmers Model C is a small row-crop tractor with a 125.2 ci (2.1 L) four-cylinder engine. For buyers and restorers, the useful checks are the serial table, fuel variant, PTO setup, and the manuals behind the parts.
Nebraska tests split the Model C by fuel: Test 363 covers the distillate tractor, while Test 364 covers the gasoline tractor. Keep tested power under the right test instead of folding the results into one blanket C rating.
Because parts and service hinge on the exact model code, serial range, and configuration, verify the tractor’s serial and configuration against the available manuals or test reports before ordering parts or performing maintenance.
Allis-Chalmers C Quick Answers
- Production yearsThe Allis-Chalmers Model C was produced from 1940 through 1949.
- PowerNebraska test data splits the Model C by fuel. The 23.30 PTO hp and 18.4 drawbar hp pair belongs to the gasoline Test 364 row. The distillate Test 363 row is separate, so do not use one test as a blanket rating for every C.
- EngineEngine displacement is 125.2 ci (2.1 L).
- How much does an Allis-Chalmers C weigh?The listed operating weight is 2,500 lb. Equipment, tires, and ballast can change the actual weight, so confirm the tractor's configuration before transport or implement matching.
- PTO and hitchRear PTO: 560.
- Service capacityEngine oil capacity is 4 qts (3.8 L); coolant capacity is 8 qts (7.6 L).
Engine and Power
Engine and power figures center on a 125.2 ci (2.1 L) four-cylinder engine running at about 1,500 rpm. Distillate and gasoline variants use the same displacement but different compression values.
Engine option 1
Allis Chalmers CE / distillate / 4-cylinder 8-valve / liquid-cooled vertical I-head / Low-octane fuel engine designed to run on tractor fuels with an octane rating of 30 or higher.
| Displacement | 125.2 ci 2.1 L |
|---|---|
| Bore Stroke | 3.375x3.50 inches 86 x 89 mm |
| Air Cleaner | oil bath |
| Compression | 4.75:1 |
| Rated Rpm | 1500 |
| Firing Order | 1-2-4-3 |
| Starter Volts | 6 |
| Coolant Capacity | 8 qts 7.6 L |
| Sparkplug | Autolite A 9 |
| Sparkplug Gap | 0.035 inches 0.889 mm |
| Point Gap | 0.020 inches 0.508 mm |
| Intake Valve Clearance | 0.010 inches (hot) 0.254 mm |
| Exhaust Valve Clearance | 0.010 inches (hot) 0.254 mm |
Gasoline engine
Allis-Chalmers CE / gasoline / 4-cylinder 8-valve / liquid-cooled
| Displacement | 125.2 ci 2.1 L |
|---|---|
| Bore Stroke | 3.375x3.50 inches 86 x 89 mm |
| Air Cleaner | oil bath |
| Compression | 5.75:1 |
| Rated Rpm | 1500 |
| Firing Order | 1-2-4-3 |
| Coolant Capacity | 8 qts 7.6 L |
| Sparkplug | Autolite AN 7 |
| Sparkplug Gap | 0.035 inches 0.889 mm |
| Point Gap | 0.020 inches 0.508 mm |
| Intake Valve Clearance | 0.010 inches 0.254 mm |
| Exhaust Valve Clearance | 0.010 inches 0.254 mm |
Manufacturer
Manufacture years
PTO and Hitch
PTO and hitch specs center on a 560 rear PTO. Match implements to PTO speed and hitch configuration for the actual machine.
Rear PTO
Rear PTO type
Fluids, Battery, and Service Facts
Maintenance highlights include engine oil capacity of 4 qts (3.8 L) and coolant capacity of 8 qts (7.6 L). Battery voltage is 6 V; spark plug gap is 0.035 in (0.889 mm) and point gap 0.020 in (0.508 mm). Fluid types, filters, belts, and battery groups should be confirmed with a parts catalog or service manual.
Fuel tank
Engine oil capacity
Battery volts
Battery Ah
Tires and Dimensions
Tire and dimension values can vary by wheel, axle, and configuration.
Configuration-specific values are split out where the same model has documented differences by engine, transmission, or equipment.
Wheelbase
Weight
Length
Width
- 5.5 inches 13 cm
- 68.5 inches 173 cm
Height
Front tire
Rear tire
Ag front
- 4.00-15
- 6-12
Ag rear
- 9-24
- 10-24
Electrical
Electrical rows are included when documented.
Ground
Charging system
Charging amps
Battery volts
Serial Number Lookup
Serial-number guidance: year tables apply within the stated range; prefixes and regional builds require documentation to apply beyond the stated range.
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
Manuals and Documents
The documents below cover operator instructions, service and parts references, and Nebraska test reports for the Allis-Chalmers Model C.
Check the fuel type and model coverage before using a document for service work, especially when a manual or report covers several variants.
Tractor test report
- Test 363: Allis-Chalmers Model C (Distillate)operation
Nebraska Tractor Test Report for Allis-Chalmers Model C (Distillate) stock tractor; test details and results.
Open source - Test 364: Allis-Chalmers Model C (Gasoline)operation
Nebraska Tractor Test Report for Allis-Chalmers Model C (Gasoline) stock tractor; test details and results.
Open source
Manual
- Allis Chalmers Model C Tractor Operator's Manualoperation, lubrication
Operator’s manual for Allis-Chalmers Model C tractor; includes starting, operation, lubrication, adjustments, and style variations.
Open source
Service manual
- Allis Chalmers Model C Tractor Service Repair Manual (AC-S,B,C)operation, lubrication, parts matching
Service manual for Allis-Chalmers Model C (and B/S); compiled and reproduced by Jensales from original factory material.
Open source - Allis Chalmers Model C Tractor Service Repair Manual - EmanualOnlineoperation, lubrication
Allis-Chalmers Model C Service Repair Manual; index topics include GENERAL INFORMATION, PERIODIC MAINTENANCE, ENGINE, FUEL SYSTEM, COOLING SYSTEM, ELECTRICAL SYSTEM, CHASSIS, SERVI
Open source
Parts catalog
- Allis Chalmers C Parts Manualparts matching
Parts manual for Allis-Chalmers Model C; 191 pages; reprint of the original factory manual with exploded views for ordering parts.
Open source
Parts Checks Before Ordering
Do not order Allis-Chalmers C parts from the model name alone. Match the part to the tractor's model code, serial range, engine, transmission, PTO setup, and build year before choosing service parts.
Filters, fluids, belts, electrical parts, clutch and PTO parts, and hydraulic parts can vary by setup. Exact part numbers need a parts catalog, manual, or trusted supplier source before they become recommendations.
Accuracy Note
Tractor specifications can vary by year, region, factory configuration, installed equipment, and later repairs. Match serial range, engine, transmission, PTO setup, and model code before ordering parts or doing service work.