Provided is an internal combustion engine lubricating oil composition having a major amount of an oil of lubricating viscosity; a combination of alkaline earth metal alkylhydroxybenzoate detergents; at least about 50 to about 500 ppm of boron from a boron containing detergent; a molybdenum containing compound in an amount to provide the lubricating oil composition from about 100 to about 1500 ppm molybdenum; a ZnDTP compound; where the composition comprises magnesium in an amount from about 100 to about 800 ppm, and calcium in an amount from about 500 to about 2000 ppm.

The present invention relates to the use of a copolymer (C) comprising repeat units corresponding to alkyl methacrylate monomers, said monomers comprising at least one or more monomer(s) (A), the same or different, selected from among (C6-C10) alkyl methacrylate monomers; one or more monomer(s) (B), the same or different, selected from among (C10-C18) alkyl methacrylate monomers, in a lubricant composition comprising at least one base oil for reducing and/or controlling abnormal gas combustion in an engine, preferably a marine engine or a controlled-ignition engine.

Lubricating composition comprising (i) base oil and (ii) a Verkade base compound having the formula (1): wherein R.sup.1, R.sup.2 and R.sup.3 are each independently selected from hydrogen and saturated or unsaturated, straight chain or branched, C.sub.1-C.sub.22 alkyl groups. The lubricating composition of the present invention exhibits improved base number retention and oxidative stability, particularly in the presence of a biofuel such as fatty acid alkyl ester. ##STR00001##

(1) A cylinder lubricating oil composition for a crosshead diesel engine, the composition having a sulfated ash content of 2.0 to 5.5 mass %; a base number of 15 to 45 mgKOH/g; and an autoignition temperature of no less than 262? C. (2) A cylinder lubricating oil composition for a crosshead diesel engine, comprising: a lubricant base oil; (B) a Ca sulfonate detergent having a base number of no less than 10 mgKOH/g and less than 60 mgKOH/g; (C) a Ca phenate detergent having a base number of 55 to 200 mgKOH/g; (D) an amine antioxidant; and (E) a zinc dithiophosphate, wherein the composition has a base number of no less than 15 mgKOH/g and less than 120 mgKOH/g.

A lubricating oil composition for internal combustion engines containing a base oil mixture with specific properties and a monoglyceride with a specific structure. The lubricating oil composition of the present 5 invention, as well as providing outstanding wear resistance and fuel economy, causes condensed water etc. from water vapor produced as a result of fuel combustion to be dispersed in the oil, so preventing corrosion or rusting of the engine.

This invention encompasses lubricating oil compositions comprising a base oil, a biodiesel fuel and a Mannich condensation product. A method for inhibiting viscosity increase in a diesel engine fueled at least in part with a biodiesel fuel is also described.

This invention encompasses lubricating oil compositions comprising a base oil, a biodiesel fuel and a dispersant. A method for inhibiting viscosity increase in a diesel engine fueled at least in part with a biodiesel fuel is also described.

Oxidative degradation may be reduced in a lubricant composition which contains an oil of lubricating viscosity and at least about 1 percent by weight of a C1-C3 alkyl ester of a carboxylic acid of about 12 to about 24 carbon atoms, by including within the lubricant composition a sulfonate detergent in an amount sufficient to provide at least about 0.2 percent by weight sulfonate soap to the lubricant composition, wherein the weight ratio of sulfonate soap to phenate soap in the lubricant composition is at least about 0.35:1.

Trunk piston marine engine lubrication, when the engine is fueled by heavy fuel oil, is effected by a composition of TBN in the range of 20 to 60 comprising a major amount of an oil of lubricating viscosity containing 50 mass % or more of a Group 1 basestock, and respective minor amounts of a calcium alkyl salicylate detergent system providing 40 to 90 mmol of calcium alkyl salicylate per kg of the composition, and 1 to 7 mass %, based on the mass of the composition, of an oil-soluble polyalkenyl-substituted carboxylic acid anhydride, wherein the or at least one polyalkenyl group is derived from a polyalkene having a number average molecular weight of from 200 to 3,000. Asphaltene precipitation in the lubricant, caused by the presence of contaminant heavy fuel oil, is prevented or inhibited.

An organometallic chemistry-based compound for preventing coke formation in a hydrocarbon fluid system. The organometallic chemistry-based compound includes a coordination complex that interrupts an autoxidative pathway of coke formation. A component and a system for mitigating coke formation during delivery or circulation of a hydrocarbon fluid. The component includes a contact surface configured to be in contact with the hydrocarbon fluid. The contact surface is functionalized with an inhibitor ligand to form an inhibitor ligand-functionalized surface. The inhibitor ligand-functionalized surface interrupts an autoxidative pathway of coke formation.