Abstract: Engine lubricating oil is removed from the engine sump, passed through a strainer and pumped at superatmospheric pressure through a heater to raise the temperature to 150.degree.-180.degree. F., a portion of the heated pressurized oil is passed through a filter and to the oil sending unit of the engine while the remainder of the heated pressurized oil is refined by filtering to remove particles above 5 microns and to vaporize and remove vaporizable contaminants; the refined oil being returned at atmospheric pressure by gravity to the engine sump.

Abstract: System for recovering purified oil from a mixture of oil, water, and solid particles; comprising allowing the mixture to settle while heating to about 160.degree. F. to form a lower water layer and an upper oil layer; pumping off the water layer and passing it through a strainer to separate solids; pumping off the oil, passing it through a strainer to remove solids, heating the strained oil and passing it through a purification step including filtering fine solids, heating the oil to vaporize any volatile components, and separating the vapors so produced.

Abstract: An oil reconditioning device includes a housing with a tightenable lid, a smooth walled chamber in the housing containing a compressible filter, a hollow, convex frustoconical element in the upper portion of the chamber having a plurality of upstanding columns for engagement by the lid when it is being tightened and firmly secured to the housing to cause increasingly a compressive force to uniformly compact the filter. The compacted filter rests on a horizontal conduit having a centrally located termination in the form of a vertical nozzle with laterally directed passages to direct oil laterally into a cavity formed in the lower surface of the filter. A small space below the filter and the bottom of the housing is connected to an outlet from which water may be drained.

Abstract: In an oil reconditioning device including a housing, a contaminated oil inlet, a filter chamber in the housing, and an upper chamber in the housing where the oil from the filter chamber drains into said outlet; the improvement which comprises a lower oil receiving chamber in the housing a plurality of spaced conduits connecting said upper chamber with said lower oil receiving chamber and an outlet in said oil receiving chamber for delivering purified oil therefrom. The oil reconditioning device of this invention eliminates problems of overflow and of engine blow by when the device is tilted at steep angles encountered in use.