A refrigeration motor compressor assembly has a housing including a lubricant sump in the bottom thereof into which the lower end of the drive shaft and associated rotor extend. A shield is provided which is supported on and positioned by the drive shaft in underlying spaced relationship to the lower end of the rotor and associated counterweight. As the rotor rotates, lubricant disposed between the shield and rotor therein is thrown outwardly across the end turns of the stator thus serving to cool same. The shield serves to restrict the return flow of oil to the area immediately below the rotor thus reducing the viscous drag on the motor yet still allowing sufficient circulation of oil to achieve the desired cooling of the stator.