This workshop service repair manual covers the International Harvester 766 tractor, manufactured from approximately 1971 to 1976. The 766 was a key model in IH's 70 Series, known for its robust build quality and versatility, offering a balance of power and operational efficiency for mid-sized farming operations. It typically featured International Harvester's reliable diesel engines, such as the D-239 or D-310, and offered transmission options including a 5-speed Power Transfer (PT) transmission and the highly sought-after Torque Amplifier (TA) system, which provided 16 forward and 8 reverse speeds for enhanced operational flexibility. With its strong industry reputation, the 766 represented a significant advancement in tractor technology for its era, prioritizing operator functionality and dependable performance.
This comprehensive manual provides detailed, factory-level repair and service information essential for maintaining and repairing the International Harvester 766. It covers all major systems, including the engine (mechanical and electrical), fuel system, emission control, clutch, manual and automatic transaxle systems, driveshaft and axle, suspension, steering, brakes, body (interior and exterior), body electrical system, and restraint system. The manual includes step-by-step repair procedures, diagnostic guidance, troubleshooting, and detailed illustrations, diagrams, and wiring schematics. It is designed to assist both owners and professional technicians in keeping their tractor in optimal working condition, offering a cost-effective solution for dealership-level information.
Make:
International Harvester
Product Type:
Workshop Service Repair Manual
Target Audience:
Owners and technicians of International Harvester 766 tractors, ranging from DIY enthusiasts to professional mechanics.
Value Proposition:
Provides a cost-effective solution for maintaining and repairing the International Harvester 766, offering dealership-level information at a fraction of the cost.
Manual Benefits:
Detailed illustrations, comprehensive coverage, step-by-step instructions, troubleshooting guidance, printable pages for workshop use.
Accuracy:
Factory-level repair and service information.
Engine Mechanical System:
True
Engine Electrical System:
True
Emission Control System:
True
Manual Transaxle System:
True
Automatic Transaxle System:
True
Driveshaft And Axle:
True
Body Interior And Exterior:
True
Body Electrical System:
True
General Information:
True
Estimated Page Count:
Comprehensive (exact count not specified, but described as 'complete' and covering 'every detail')
Type:
Workshop Service Repair Manual
Digital Requirements:
Adobe PDF Reader & WinZip
Compatibility:
All Versions of Windows & Mac
All Major Systems:
Engine mechanical, engine electrical, fuel system, emission control, clutch, manual transaxle, automatic transaxle, driveshaft, axle, suspension, steering, brakes, body (interior and exterior), body electrical, and restraint systems.
Repair Procedures:
Detailed step-by-step instructions, substeps expanding on repair procedures, troubleshooting and electrical service procedures, diagnostic procedures.
Maintenance Procedures:
Implied through 'keeping your vehicle working properly' and detailed diagrams/illustrations for service.
Depth Of Information:
Comprehensive, covering every detail from general information to specific system repairs, suitable for both do-it-yourselfers and experienced mechanics.
Visual Aids:
Detailed illustrations, diagrams, photos, and wiring schematics.
Ease Of Use:
Numbered table of contents for fast information retrieval, bold figure numbers for matching illustrations with instructions.
Printability:
Fully Printable
Delivery Method:
Instant Download
Engine Options:
The International Harvester 766 tractor was typically equipped with a choice of International Harvester's own diesel engines. Common options included the D-239 and D-310 engines. Specific engine displacement, bore, stroke, and compression ratios would be detailed within the manual.
Horsepower And Torque:
Specific horsepower and torque figures for various engine configurations (e.g., D-239, D-310) and potential de-rated versions for different applications would be found in the manual's specifications section.
Injection System:
Likely mechanical direct injection, potentially with rotary or inline injection pumps from manufacturers like CAV, Stanadyne, or Bosch, depending on the specific engine and build date. Manual would detail pump timing and calibration.
Cooling Type:
Water-cooled
Oil Type And Capacity:
The manual would specify the exact API service classification (e.g., CD or CE for diesel engines of that era) and viscosity grade (e.g., SAE 15W-40 or 30) for engine oil, along with the total oil capacity including filter.
Gearbox Options:
The 766 offered a range of transmissions. A primary option was the 'Power Transfer' (PT) 5-speed synchronized transmission. An optional 'Load-Star' or 'Torque Amplifier' (TA) transmission, providing 16 forward and 8 reverse speeds with clutchless shifting between ranges, was also a significant feature. The manual would cover both.
Transmission Types:
While a manual transmission was standard, the 'Torque Amplifier' (TA) was a highly sought-after option, significantly enhancing operational versatility and reducing operator fatigue.
Transmission Features:
Synchronized shifting, optional Torque Amplifier for on-the-go range changes, heavy-duty final drives.
Transmission Fluid Type:
The manual would specify the appropriate lubricant for the manual transmission and the hydraulic/transaxle fluid for the Power Transfer or Torque Amplifier systems, likely an IH Hy-Tran fluid or equivalent. Capacities for each would be listed.
Overall Length:
Approximately 135 inches (3429 mm) without front weights or mounted implements. Specific dimensions vary slightly by configuration.
Overall Width:
Approximately 72 inches (1829 mm) at the rear wheels, adjustable. Specific width depends on tire and wheel configuration.
Wheelbase:
Approximately 84 inches (2134 mm).
Operating Weight:
Around 5,500 - 6,500 lbs (2495 - 2948 kg) depending on configuration and options. The manual would provide exact weights for various configurations.
Drawbar Horsepower:
The 766 was rated for approximately 55-60 PTO horsepower, which translates to a specific range of drawbar horsepower, a key metric for tractor performance.
Operator Interface:
Basic analog gauges for engine temperature, oil pressure, fuel level, and tachometer. Functionality focused on operational status and driver input (lever controls).
Control Systems:
Mechanical linkage for steering, clutch, and transmission engagement. The optional Torque Amplifier provided a form of 'assist' for gear changes. Hydrau-Lift or similar 3-point hitch system for implement control.
Power Take Off:
Standard 540 RPM PTO, with an optional 1000 RPM PTO available on some models or configurations. The manual would cover PTO engagement and maintenance.
Engine Oil Change:
Typically every 250 hours of operation or annually, whichever comes first. The manual will detail the exact interval based on operating conditions.
Fuel Filter Replacement:
Scheduled replacement at regular intervals, often coinciding with oil changes or based on engine hours, to ensure proper fuel system operation.
Hydraulic Fluid Filter Replacement:
Recommended at intervals typically specified in the manual, crucial for maintaining the life of the hydraulic system.
Coolant Type:
The manual will specify the correct type and mixture of antifreeze/coolant for the engine's cooling system, typically a conventional ethylene glycol-based coolant with a suitable inhibitor package.
Transmission Hydraulic Fluid:
International Harvester Hy-Tran fluid or an equivalent meeting the specified performance standards would be recommended for the transmission and hydraulic systems. The manual will provide the specific type and viscosity.
Common Wear Items:
Like many tractors of this era, common wear items can include clutch components, brake linings, hydraulic pump and seals, and wear on the Torque Amplifier drive components if equipped. The manual would cover diagnostics and repair for these.
Electrical System Concerns:
Wiring harness integrity, starter motor reliability, and alternator output can be areas requiring attention over time. The detailed wiring schematics in the manual are invaluable for troubleshooting.
Greasing Points:
Regular lubrication of all grease points (e.g., kingpins, tie rod ends, PTO shafts, hitch points) is critical for longevity. The manual would provide a lubrication chart.
Manufacturer History:
International Harvester (IH) was a prominent American manufacturer of agricultural and construction equipment, as well as vehicles. Founded in 1902, IH produced iconic tractors for generations before merging with J.I. Case to form Case IH in 1985.
766 Model Line:
The 766 was part of IH's '70 Series' of tractors, introduced in the early 1970s as a successor to earlier models like the 656 and 666. It represented a modernization of IH's tractor line with improved ergonomics and increased power. It was produced from approximately 1971 to 1976.
Production Period:
The International Harvester 766 was manufactured from approximately 1971 through 1976.
Manufacturing Plants:
Primarily manufactured at International Harvester's major tractor assembly plants in the United States, such as Rock Island, Illinois, and Louisville, Kentucky.
Industry Reputation:
The International Harvester 766, as part of the 70 Series, was generally well-regarded for its power, versatility, and robust build quality, making it a popular choice for mid-sized farming operations.
