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How many hrs of use since hyd oil level was checked, hyd filter changed & hyd oil suction screen checked/cleaned???? 3pt dropping after stopping operation of engine could be caused from failed rockshaft piston seals or leaking rockshaft control valves. With hyd oil at operating temp, engine operating, 3 pt raised look into open hyd filler hole behind seat for moving/spraying oil. Moving oil indicates afore mentioned internal hyd leak locations.