Method for improving deposit control

摘要

A method for improving deposit control, while maintaining or improving demulsibility performance, in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil that has a particular phenate/carboxylate detergent mixture present in a particular amount in the formulated oil. A lubricating engine oil having a composition including a lubricating oil base stock as a major component; and a phenate/carboxylate detergent mixture as a minor component. The lubricating oils of this disclosure are useful in marine crankcase systems, in particular, marine system oil applications for two-stroke marine diesel engines.

主权项

1. A method for improving deposit control, while maintaining or improving demulsibility performance, in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil, said formulated oil having a composition comprising a lubricating oil base stock as a major component; and a detergent mixture comprising a first detergent comprising an overbased phenate compound at from 1.0 to 1.5 wt. % of the lubricating oil, and at least one other detergent different from said first detergent wherein the at least one other detergent comprises a carbonated calcium monosalicylate (carboxylate) at from 2.0 to 3.0 wt. % of the lubricating oil, and the amount of the detergent mixture is at least 3.5 wt. % in the lubricating oil with the proviso that the lubricating oil does not include a dispersant, wherein the lubricating oil exhibits improved deposit control, while demulsibility performance is maintained or improved, as compared to deposit control and demulsibility performance achieved using a lubricating oil not containing the detergent mixture in the lubricating oil.