LUBRICATING OIL COMPOSITIONS

摘要

An improved polybutene-free lubricant composition for marine diesel engines, comprising a major amount of oil of lubricating viscosity and, provided by admixing therewith, minor amounts of a) at least one of a borated dispersant or oil-soluble or oil-dispersible boron compound; and b) one or more overbased metal compounds, the or each compound having a TBN of at least 300, with the proviso that if an overbased metal salicylate is present then the TBN of said salicylate is at least 200; wherein the TBN of the composition is at least 10 and the viscosity index of the composition is at least 90.