Mec 3072RT, Service Manual

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March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page 1-2
HYDRAULIC SYSTEM - GENERAL
The hydraulic system is an open center, open- loop type. Generally in this type of system, hydrau-
lic fluid is provided by a variable displacement, pressure compensated, piston type pump which is
directly coupled to the engine. As the engine turns, the hydraulic pump drains oil from the reser-
voir and pumps this fluid to the valve packages.
If no function is selected to perform, the pump remains on standby and no fluid is pumped
through the manifold. Each function has a maximum pressure control limit set by pressure relief
valve.
Hydraulic integrated circuit, generally known as the manifold system (valve type) is designed to
control all or part of machine functions by integrating various hydraulic cartridge valves into a
manifold to provide directional, pressure, flow, and load control.