A hand-operated hydraulic pump utilized to lift or trim an outboard marine engine. A wobble-action handle connects with a pinion gear which in turn drives a rack on a double-ended piston forming two cylinder chambers on opposite ends thereof. Reciprocal movement of the piston alternately pumps fluid from each cylinder chamber both of which are supplied by a common longitudinal passage in the piston across a pair of check valves located at each end of the piston. The pump housing includes the reservoir, discharge port and needle valve for relieving fluid from the discharge port back to the reservoir.