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.