Official International Harvester Shop Manual: 706-21456 Tractor Series - Service, Repair & Troubleshooting 1963-1971

International Harvester Tractor Series 706-21456 Official Shop Manual

Keep your vintage iron running like new with this definitive, professional-grade shop manual. This is not a simple owner’s guide; it is the complete technical authority for the legendary International Harvester 06, 56, and 456 series tractors. Whether you are performing a routine oil change or a full engine overhaul, this manual provides the factory-spec data and step-by-step procedures required for a job done right.

Complete Model Coverage

This manual is specifically engineered to cover both Farmall and International chassis configurations across the following models:

• International 706 (1963-1967)
• International 756 (1967-1971)
• International 806 (1963-1967)
• International 856 (1967-1971)
• International 1206 (1965-1967)
• International 1256 (1967-1969)
• International 1456 (1969-1971)
• International 2706, 2756, 2806, 2856 (Industrial/Utility)
• International 21206, 21256, 21456 (Industrial/Utility)
• Farmall 706, 756, 806, 856, 1206, 1256, 1456

Professional Technical Value

This manual provides unique, model-specific data that goes beyond basic maintenance:

• Engine Mastery: Comprehensive teardown and rebuild specs for IH Gas (C263, C291, C301), LP-Gas, and the powerful Diesel/Turbo-Diesel variants (D282, D310, D361, DT361, D407, DT407). Includes critical piston-to-sleeve clearances and valve timing.
• Advanced Transmission Care: Detailed service for the Torque Amplifier (TA) and Speed Transmission. Learn how to troubleshoot the TA lock-up clutch and adjust shifting linkages for smooth operation.
• Hydraulic & Power Steering: Full diagnostics for the 9 GPM hydraulic pump and the Multiple Control Valve (MCV) system. Includes pressure test procedures (1800-1900 psi relief settings) and steering wheel slip tests.
• All-Wheel Drive & Final Drives: Exclusive sections on the front drive axle for 4WD models, including differential carrier bearing preload and bull gear maintenance.
• Essential Torque Specs: Never guess a bolt again. Includes factory torque values for cylinder heads (up to 135 ft-lbs on DT407), main bearings, and manifolds.

Key Identification Data

To ensure you are working on the correct component, use the serial number locations specified in the manual:

• Tractor Serial Number: Located on the nameplate on the right side of the clutch housing.
• Engine Serial Number: Found on the left side of the crankcase for most models. For D-310 diesel engines, it is located on the right side.

Clear Buyer Benefits

• Minimize Downtime: Use the targeted Troubleshooting Guide to identify issues like hard steering or hydraulic lift failure before they lead to expensive failures.
• Precision Repairs: Verbatim factory clearances (down to 0.0001 inch) ensure your rebuild meets original International Harvester standards.
• Save Money: Perform complex tasks yourself, such as adjusting the four-pinion differential or bleeding the power brake system, without the need for a commercial shop.
• Optimized Performance: Detailed tune-up data for injection pump timing and governor synchronization ensures your tractor delivers maximum horsepower and fuel efficiency.

This manual is the ultimate investment for the IH enthusiast or agricultural professional. It provides the clarity and technical depth needed to preserve the heritage and productivity of your International Harvester machinery for years to come.