An air-driven pump includes a source of compressed air, a vacuum source including a venturi and two pump units with structurally independent pumping elements dividing pump chambers from air chambers. A directional control valve is in communication with the source of compressed air, the vacuum source, the pump unit air chambers. The directional control valve includes two valve positions alternating communication of the source of compressed air and the vacuum source with the air chambers. A pilot valve system shifts the directional control valve between the two valve positions at end of stroke positions of the pump and includes actuators extending into the air chambers to engage the pumping elements with the air chambers contracted.