Target Audience:
Owners, technicians, and enthusiasts performing maintenance and repair on IH 666 & 686 tractors.
Application Sector:
Agricultural, farming, and heavy-duty tractor service.
Value Proposition:
Provides comprehensive service information in an accessible digital format, offering cost savings over printed manuals and physical service calls.
Digital Enhancements:
Improved PDF with bookmarks, searchable text, and index for efficient navigation and information retrieval.
Accessibility:
Instant download, no waiting, viewable on any computer, zoomable, and printable.
Primary Coverage:
IH International Harvester 666 and 686 Tractors
Engine Types Covered:
Diesel & Non-Diesel variants
Estimated Page Count:
Not specified, but implied comprehensive coverage for workshop service.
Type:
Service/Workshop/Repair Manual
Digital Features:
Bookmarks, Searchable Text, Index
Engine Systems:
Engine Overhaul, Fuel System (Diesel & LP Gas), Cooling System, Governor
Drivetrain Systems:
Clutch, Transmission Range, Torque Amplifier, Direction Reverser, Hydrostatic Drive (if applicable), Differential, Final Drive
Chassis And Controls:
Brakes, Steering Gear, Power Steering System, Front System, Belt Pulley, Power Takeoff (PTO)
Electrical Systems:
Electrical System Diagnosis and Repair
Carburetor Details:
Specific procedures for disassembly, cleaning, adjustment, and troubleshooting of the carburetor (for gasoline/petrol variants).
Lp Gas System Details:
Comprehensive coverage of LP Gas fuel systems, including tank, regulator, vaporizer, and fuel lines.
Steering System Coverage:
Detailed diagnostics and repair procedures for both manual steering gear and power steering systems.
Front System Coverage:
Includes repair and maintenance of front axle components, steering linkages, and front wheel bearings.
Belt Pulley Coverage:
Information on the maintenance and potential repair of the belt pulley system for power take-off applications.
Hydraulic System Components:
Coverage of the hydraulic pump, control valve, lift cover, cylinders, and associated plumbing for implement operation.
Transmission Overhaul:
Detailed step-by-step instructions for complete transmission disassembly, inspection of gears and bearings, and reassembly.
Brake System Components:
Coverage of brake master cylinder, wheel cylinders, brake lines, and brake pedal adjustments.
Maintenance Procedures:
Tune-ups, regular maintenance, fluid changes, lubrication
Repair Procedures:
Component removal, installation, adjustment, overhaul, troubleshooting
Diagnostic Procedures:
Troubleshooting guides, fault finding for various systems
Torque Specifications:
Essential torque specifications for critical fasteners across all systems will be provided in the 'Service Data' section.
Troubleshooting Guides:
Systematic troubleshooting guides to diagnose common operational problems and their remedies.
Depth Of Information:
Detailed technical instructions, diagrams, and manufacturer specifications for maintenance and repair.
Diagrams And Illustrations:
Abundant use of diagrams and illustrations to clarify assembly, disassembly, and repair procedures.
Searchability Benefit:
Keyword search functionality allows users to quickly locate information on specific components or problems.
Print Capabilities:
Print entire manual or select sections, high-quality reproduction.
User Printing Benefit:
Enables users to print only the necessary pages for a specific task, saving paper and preventing damage to a primary copy.
Binding:
Not applicable (PDF format)
Paper Quality:
Not applicable (PDF format), user printable on desired paper.
Operating Systems:
Windows, Mac
Reader Software:
Requires Adobe Acrobat Reader (latest version recommended for optimal display).
Engine Details:
Covers both Diesel and Non-Diesel engine configurations common to IH 666 & 686 models. Specific engine displacements, bore/stroke, and compression ratios will be detailed within the manual.
Horsepower Torque:
Specifications for horsepower and torque output for various engine options will be included in the 'Service Data' section.
Fuel System Types:
Detailed coverage of Diesel fuel injection systems, LP Gas fuel systems, and Carburetor systems.
Cooling System Coverage:
Covers radiator, fan, water pump, thermostat, and coolant specifications/procedures.
Safety Standards:
The manual will adhere to industry standards for safe repair practices, highlighting critical safety procedures.
Brake System Safety:
Detailed procedures for brake system inspection, adjustment, and repair to ensure safe operation.
Operator Station Safety:
While not explicitly stated as a feature of this service manual, safe operating procedures and component integrity checks contribute to operator safety.
Scheduled Maintenance:
The manual will provide detailed recommended service intervals for engine oil changes, filter replacements, lubrication points, and other routine maintenance tasks.
Engine Oil Type:
Specific API service classifications and SAE viscosity grades for engine oil will be listed (e.g., SAE 30, 10W-30, etc., depending on ambient temperature).
Hydraulic Fluid Type:
Specifications for hydraulic fluid, including type and capacity, will be detailed for the hydraulic system and transmission/rear axle where shared.
Coolant Type:
Recommended coolant mixture (antifreeze type and concentration) for the cooling system will be specified.
Common Wear Items:
While not explicitly listed, typical wear items for tractors of this era often include clutch components, brake shoes/discs, hydraulic pump seals, and certain engine gaskets. The manual will guide on inspection and replacement.
Governor Servicing:
Specific guidance on the maintenance and repair of the engine governor, critical for consistent engine speed.
Transmission Adjustment:
Procedures for adjusting transmission clutch, linkage, and torque amplifier operation.
Manufacturer Legacy:
International Harvester (IH) has a long and respected history in agricultural machinery, known for robust and reliable tractors.
666 686 Positioning:
The 666 and 686 models were part of IH's established tractor lineup, offering improvements and variations over previous generations.
Model Differentiation:
The manual addresses both the 666 and 686 models, indicating it covers variants and potential differences between them.
Production Period:
Typically produced in the late 1960s and 1970s, representing a significant era in agricultural mechanization.
