This operator manual covers the Orenstein & Koppel (O&K) RH6 crawler excavator and loader. Designed for robust performance in demanding environments, the RH6 is engineered for reliability and efficiency in excavation and loading tasks. Its comprehensive system coverage ensures optimal operation and longevity for this versatile piece of heavy machinery. This manual serves as a definitive guide for understanding, operating, and maintaining your O&K RH6. It details essential procedures and technical information, including the electrical and hydraulic systems, fuel and braking systems, undercarriage components, and lubrication requirements. With clear explanations and diagrams, this manual empowers operators and technicians to perform routine maintenance, troubleshoot issues, and ensure the continued high performance of the RH6.