Abstract: An oil separator for blow-by gases formed in internal combustion engines includes a nozzle that has a plurality of holes located in the air flow path of the blow-by gases. The diameter of the holes and the thickness of the nozzle results in the flow of blow-by gases being accelerated as the gases flow through the nozzle so that small droplets of oil in the blow-by gases tend to be formed into fewer and larger oil droplets. A portion of the oil droplets will coalesce on the outer surface of the nozzle and drain to an oil drain. The remainder of the accelerated blow-by gas flows through an air gap adjacent the outer surface of the nozzle onto an impervious impingement plate or surface. At least a substantial portion of the remaining oil droplets in the blow-by gases will coalesce on the impingement surface and flow along the impingement surface to the oil drain for reintroduction into the oil reservoir of the engine. The cleansed blow-by gases then flow out of the oil separator through an outlet.