Closed center system... oil circulation stops when there's no demand... pump "goes out of stroke" and pumps only enough oil to keep system at "standby pressure" saving power and reducing heat.
The way it was taught to me in JD tech school. When pressure stabilizes above set stand-by pressure(2250 psi is factory setting),trapped oil in crankcase of hyd pump(caused by stroke control valve closing) forces pistons away from pump crankshaft causing no oil to be pumped and psi is trapped in lines. When crankcase pressure drops pistons are pushed by springs back against turning crankshaft and pumping commences.
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Today's Featured Article - Chores - by Frank Young. The ceaseless passing of time! It is at once our friend and our enemy. It measures our progress and it makes us old. Like most features of our life, few things are all good or all bad, and most such judgments depend on our own perspective or viewpoint. In our particular hobby, we enjoy the nostalgic return to the days of our youth as we recreate many of the scenes that took place on the family farm that served as the stage for the first few acts of the play that is our live
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