Segment:
Heavy-duty agricultural tractor.
Target User:
Farmers, agricultural businesses, tractor restorers, mechanics specializing in vintage farm equipment.
Comparison:
Competed with other heavy-duty tractors from manufacturers like John Deere, International Harvester, and Ford during its production era.
Power:
Designed for heavy draft work, offering significant pulling power and hydraulic capacity for its time.
Durability:
Known for robust construction and reliability in demanding agricultural conditions.
Versatility:
Capable of operating a wide range of implements, including plows, cultivators, mowers, and loaders.
Primary Coverage:
Complete service, repair, troubleshooting, and maintenance of the Allis-Chalmers Model D-21 Tractor.
Estimated Page Count:
Extensive (specific count not provided, but implied as comprehensive for a WSM).
Type:
Workshop Service Manual (WSM)
Engine:
Detailed breakdown, overhaul, timing, fuel system, lubrication, cooling, ignition, and starting systems.
Transmission:
Service, repair, and adjustment of the transmission, clutch, and associated driveline components.
Hydraulics:
Repair and maintenance of the hydraulic system, including pump, cylinders, control valves, and fluid lines.
Electrical:
Wiring diagrams, troubleshooting for lighting, starting, charging, and accessory systems.
Chassis:
Front axle, steering, rear axle, brakes, and suspension system service.
Power Takeoff:
PTO engagement, operation, and repair of both independent and transmission-driven PTOs.
Cooling System:
Radiator, fan, thermostat, water pump, and coolant specifications and maintenance.
Fuel System:
Carburetor (if applicable), fuel pump, filters, injection system troubleshooting and repair.
Maintenance:
Scheduled maintenance intervals, lubrication charts, fluid changes, filter replacements.
Troubleshooting:
Diagnostic procedures, symptom-based troubleshooting guides, common problem identification.
Repair Overhaul:
Step-by-step instructions for complete disassembly, inspection, repair, and reassembly of all major components.
Adjustment:
Alignment, linkage adjustments, brake adjustments, clutch adjustments, and PTO adjustments.
Testing:
Diagnostic tests, performance checks, and calibration procedures for various systems.
Depth:
Comprehensive, covering basic maintenance to complete engine and transmission rebuilds.
Diagnostics:
Advanced diagnostic procedures and schematics for electrical and hydraulic systems.
Make Model:
Allis-Chalmers 3400 Series (typically a six-cylinder diesel).
Configuration:
Inline 6-cylinder, naturally aspirated diesel.
Displacement:
Approximately 301 cubic inches (4.9 Liters) - specific displacement may vary slightly by exact engine variant.
Bore X Stroke:
Refer to manual for exact dimensions. Typical for this era would be around 3.875" x 4.375".
Horsepower Rated:
Estimated 65-75 PTO horsepower (exact figures depend on engine tuning and specific model year).
Torque Rated:
Significant torque for heavy draft applications, specific figures available in manual.
Injection System:
Typically Roosa Master or similar rotary injection pump system.
Type:
Pressurized, forced lubrication with oil pump and filter.
Type:
Constant Mesh Transmission (CMT) with multiple forward and reverse gears.
Gear Count:
Likely 8 forward speeds and 2 reverse speeds, or similar configuration.
Features:
Optional features might include a differential lock, creeper gears, or power adjust rear wheels depending on configuration.
Clutch:
Dual-stage or single-stage dry clutch for transmission and independent PTO engagement.
Final Drive:
Heavy-duty spur gear final drives.
Transmission Oil Type:
Refer to manual for specific API GL-4 or GL-5 lubricant specifications and viscosity grade (e.g., SAE 80W-90 or 90).
Length:
Refer to manual for exact dimensions; typically around 140-150 inches.
Width:
Refer to manual for exact dimensions; typically around 70-80 inches at rear wheels.
Height:
Refer to manual for exact dimensions (at steering wheel or exhaust).
Operating Weight:
Approximately 8,000 - 9,500 lbs (without ballast).
Wheelbase:
Refer to manual for exact dimensions; typically around 90-95 inches.
Rollover Protection:
ROPS (Roll-Over Protective Structure) was an option, not standard equipment on all models. Manual will cover installation and maintenance if equipped.
Brakes:
Hydraulically actuated, internal expanding shoe brakes on rear axle. Parking brake mechanism included.
Operator Station:
Open operator station; manual covers safe operation and attachment procedures.
Engine Oil Change:
Typically every 100-150 operating hours, refer to manual for exact interval and oil type.
Fuel Filter Replacement:
Regular intervals based on fuel quality, often 250-500 hours or as needed.
Air Filter Service:
Service based on operating conditions, daily inspection recommended.
Engine Oil Type:
Consult manual for specific API Service classification and viscosity grade (e.g., API CD or CE, SAE 30 or 15W-40).
Coolant Type:
Ethylene glycol antifreeze mixture. Manual will specify mix ratio and corrosion inhibitor requirements.
Hydraulic Fluid Type:
Tractor Hydraulic Fluid (THF) or equivalent. Manual will specify brand compatibility and viscosity.
Common Wear Items:
Hydraulic pump wear, PTO clutch wear, potential for injection pump issues, seals and gaskets.
Electrical Gremlins:
Age-related wiring degradation, corroded connections, starter/generator issues.
Greasing:
Regular greasing of pivot points, kingpins, and PTO shaft is crucial.
Brand Origins:
Allis-Chalmers was a prominent American manufacturer of agricultural machinery and industrial equipment, known for its distinctive 'Allis-Chalmers Orange' color.
Predecessors:
The D-21 was part of Allis-Chalmers' 'D' series tractor line, which saw continuous development and improvement through the mid-20th century.
Production Years:
The D-21 was primarily produced from 1963 to 1967.
Manufacturing Location:
Gatedwood, Wisconsin, USA.
