LUBRICATING OIL COMPOSITIONS

摘要

A lubricating oil composition suitable for use in low- or medium-speed diesel engines, especially a four-stroke trunk piston engine, comprises a fuel oil with a residual oil content characterised in that the lubricating oil composition further comprises a "black paint" reducing amount of a demulsifier for water-in-oil emulsions, for example a polyoxyalkylene polyol, and desirably also a dispersant, e.g. a hydrocarbyl-substituted succinimide. Also a method of reducing black paint in a low- or medium-speed diesel engine.