a hydraulic oil well pumping arrangement employs a compensating type hydraulic pump , a directional valving arrangement and a proportioning valving arrangement . when the directional valve is energized , oil is directed to the rod end of the hydraulic cylinder . in one embodiment , a time delay halts the movement of the sucker rod or pumping string to allow accumulation of oil in a slow following well . in another embodiment , the pumping string rapidly falls to the bottom of the stroke in order to shake or jar debris from the string .