This workshop repair service manual covers the 1390, 1394, and 1490 tractor models. These models represent a significant period of production likely spanning the late 1970s into the 1980s. These tractors, powered by diesel engines, are characterized by robust agricultural chassis and manual transmissions, offering reliable performance for demanding tasks. Their engineering quality and heritage contribute to their enduring value for owners and operators. This comprehensive manual provides professional-level technical information for all models, engines, trim, and transmission types. It details routine maintenance, advanced troubleshooting, and repair procedures for all major systems, including the engine, lubrication, cooling, fuel, transmission, drive chain, axles, brakes, steering, hydraulics, and electrical systems. With hundreds of pages of diagrams and specific instructions, this English-language manual is designed to assist owners, operators, and technicians in maintaining and repairing their tractors, ensuring optimal performance and longevity while enabling potential cost savings.