Abstract: A piston molding machine comprising a base on which a pair of mold supports are mounted for movement in a straight line toward and away from one another. A mold half is mounted on each support, and when the mold halves are juxtaposed they provide a cavity for forming a piston. A mold cap is pivoted to each mold half about a transverse axis rearwardly of the face of the mold half. A piston motor extends between each cap and its respective mold support for pivoting the mold cap into position adjacent the mold half to define the top of the cavity and away from the mold half to provide clearance for removal of a piston formed in the mold.