Prerequisite: JDAT1440, 1441, 1442, 1443. Introduction to basic hydraulic concepts, principles, symbols, and safety. Theory and construction of open-center and closed-center systems, pumps, valves, cylinders, motors, accumulators, and testing equipment as used on John Deere Equipment. Theory of operation of low pressure, high pressure, and control systems. Theory and function of load sense systems, cooling lube circuits, and pilot oil. Diagnostic testing and repair of hydraulic components and systems.