Abstract: A fully variable output hydraulic pump includes a main casing having a fluid pumping chamber extending therethrough, fluid input ports and fluid output ports. The fluid pumping chamber is shaped to receive a pair of cylindrically shaped gears inserted axially therethrough. A first rotatable gear and second rotatable gear are insertable through the pumping chamber. The first and second gears are rotatably supported by respective means which are axially translatable relative to each other. A means for sealing the area between the gears and the main casing effectively creates a sealed fluid pumping chamber. By translating one of said means for rotatably supporting the gears, the effective fluid pumping volume within the fluid pumping chamber may be altered to provide a fully variable output hydraulic pump.