Piston pump and method of manufacturing the same

A piston pump comprising:

• a pump housing having
• an extrusion-formed crankshaft chamber comprising a top chamber wall integrally extrusion-formed with at least one side chamber wall and integrally extrusion-formed with a bottom chamber wall, each of the top, bottom, and at least one side chamber walls having an extrusion-formed interior surface and an extrusion-formed exterior surface,
• a pumping chamber, and
• one or more piston passages, the piston passages extending from the crankshaft chamber to the pumping chamber;
• a crankshaft rotatably mounted in the crankshaft chamber, the crankshaft having a longitudinally extending crankshaft rotation axis, and
• one or more cams distributed along the crankshaft axis;
• and
• one or more pistons, each piston corresponding to a cam of the one or more cams, each piston slidably mounted in a corresponding piston passage of the one or more piston passages between a nose position and a heel position, each piston having
• a piston shaft extending within the corresponding piston passage, the piston shaft having a first shaft end positioned in the crankshaft chamber and a second shaft end, the first shaft end having a cam engagement side in contact with the corresponding cam
• wherein the extrusion-formed crankshaft chamber has an extrusion direction parallel to the crankshaft rotation axis.