A refrigeration compressor assembly includes a motor compressor mounted within a hermetically sealed shell with a sump area at the bottom containing a lubricating oil. An oil stirrer is secured to the crankshaft below the motor components and includes a hub secured to the crankshaft and a conical, smooth, imperforate skirt extending outwardly and downwardly below the oil surface. The oil stirrer is formed of a plastic insulating material which does not permit the formation of eddy currents within the oil stirrer from the motor flux leakage and whose surface is not wetted by the lubricating oil.