This workshop repair service manual covers Case IH models 1490, 1494, 1594, and 1690. These agricultural tractors are known for their robustness and efficiency, built upon Case IH's long heritage of providing reliable farm equipment. Designed for demanding agricultural tasks, these models represent durable workhorses that have evolved to offer improved power and serviceability. The engineering quality and reliability of Case IH equipment ensure consistent performance in challenging environments. This comprehensive manual provides detailed information for owners, operators, and mechanics. It covers essential areas including engine service, lubrication, cooling, fuel, clutch, transmission, drive axles, brakes, steering, hydraulic, and electrical systems. With step-by-step repair procedures, maintenance schedules, diagnostic guidance, and troubleshooting sections, this manual empowers users to maintain and repair their Case IH tractors effectively. It includes detailed diagrams and critical specifications, enabling advanced diagnostics and complete overhauls, ultimately helping to save on service and repair costs.