The Evaluation of Sludge Inhibition Qualities of Motor Oils in a Gasoline Engine

This test method is designed to evaluate the ability of an automotive crankcase lubricant to inhibit the deposition of sludge in gasoline engines when operated on a fuel that is prone to generate such deposits. Lubricants intended for use only in gasoline engines and those intended for mixed fleet application covering both gasoline and diesel engined vehicles may be evaluated by this procedure. Results of tests run under this method are presented on a merit rating scale from 0 (extremely heavy sludge) to 10 (clean). Certain parts of the engine, the rocker cover, cylinder head, oil tube, timing case cover and sump are rated individually and an average sludge rating is calculated from these separate numbers. Lubricants giving satisfactory performance in this test, and meeting the other, well established performance requirements, will give enhanced protection against the deposition of sludge when utilised in four stroke gasoline fuelled vehicles in both normal and severe service.Cross Reference: