Abstract: A method for testing engine lubricating oil under simulated engine operating conditions including a tank with an interior space containing a quantity of engine lubricating oil, an elongated tubular enclosure for passing oil from one end to the other, and an oil pump to cause oil to flow from the tank through the tubular enclosure. The tank includes devices to introduce oil oxidizing agents to the oil. A metal rod extends centrally through the enclosure so that oil passes along its outer surface and the rod is selectively heated so that oxidation deposits form along the rod. Examination and analysis of the rod and its deposits permit rating of a particular oil for its oxidation resistant properties.

Abstract: An apparatus for testing engine lubricating oil under simulated engine operating conditions including a tank with an interior space containing a quantity of engine lubricating oil, an elongated tubular enclosure for passing oil from one end to the other, and an oil pump to cause oil to flow from the tank through the tubular enclosure. The tank includes devices to introduce oil oxidizing agents to the oil. A metal rod extends centrally through the enclosure so that oil passes along its outer surface and the rod is selectively heated so that oxidation deposits form along the rod. Examination and analysis of the rod and its deposits permit rating of a particular oil for its oxidation resistant properties.