Abstract: A gas engine lubricating oil composition comprises an oil of lubricating viscosity including at least 90 mass % saturates and no more than 0.03 mass % to sulfur, a metal hydroxybenzoate detergent additive, a dispersant additive, and an aminic or phenolic antioxidant additive, and has a boron concentration, of zero or less than 90 ppm by mass, where boron, if present, is provided at least in part by a boron-containing dispersant additive. The composition exhibits improved lead corrosion properties and no adverse anti-wear properties.

Abstract: 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.

Abstract: A two-stroke, cross-head, slow-speed, compression-ignited marine engine is operated by (i) fuelling it with a diesel fuel, as a pilot fuel, and with a low sulphur fuel, as a main fuel; and (ii) lubricating the engine cylinder(s) with a lubricant having a BN of 20 or less and having a detergent additive system comprising at least two different metal detergents each having one surfactant group selected from phenate, salicylate and sulphonate, or one or more complex metal detergents containing two or more different surfactant soap groups selected from phenate, salicylate and sulphonate.

Abstract: A gas engine lubricating oil composition comprises an oil of lubricating viscosity including at least 90 mass % saturates and no more than 0.03 mass % to sulfur, a metal hydroxybenzoate detergent additive, a dispersant additive, and an aminic or phenolic antioxidant additive, and has a boron concentration, of zero or less than 90 ppm by mass, where boron, if present, is provided at least in part by a boron-containing dispersant additive. The composition exhibits improved lead corrosion properties and no adverse anti-wear properties.

Abstract: A lubricant additive comprising an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent dispersed in a diluent comprising 10 mass % or more of a basestock containing greater than or equal to 90% saturates and less than or equal to 0.03% sulphur is blended, in a minor amount, with an oil of lubricating viscosity, in a major amount, to give a trunk piston marine engine lubricating oil composition for a medium-speed four-stroke compression-ignited marine engine.

Abstract: A two-stroke, cross-head, slow-speed, compression-ignited marine engine is operated by (i) fuelling it with a diesel fuel, as a pilot fuel, and with a low sulphur fuel, as a main fuel; and (ii) lubricating the engine cylinder(s) with a lubricant having a BN of 20 or less and having a detergent additive system comprising at least two different metal detergents each having one surfactant group selected from phenate, salicylate and sulphonate, or one or more complex metal detergents containing two or more different surfactant soap groups selected from phenate, salicylate and sulphonate.

Abstract: A two-stroke, cross-head, slow-speed, compression-ignited marine engine is operated by (i) fuelling it with a diesel fuel, as a pilot fuel, and with a low sulphur fuel, as a main fuel; and (ii) lubricating the engine cylinder(s) with a lubricant having a BN of 20 or less and having a detergent additive system comprising one or more different metal detergents having a surfactant group selected from phenate, salicylate and sulphonate, or one or more complex metal detergents containing two or more different surfactant soap groups selected from phenate, salicylate and sulphonate, and a distilled cashew nut shell liquid or hydrogenated distilled cashew nut shell liquid.

Abstract: Lubricant additives comprising as overbased metal hydrocarbyl-substituted hydroxybenzoate detergent dispersed in diluent and a polyalkenyl-substituted carboxlic acid anhydride dispersed in a diluent oil containing 50 mass % or more of a basestock containing greater than or equal to 90% saturates and less than or equal to 0.03% sulphur or a mixture thereof are blended, in minor amounts, with a high saturates content oil of lubricating viscosity, in a major amount, to give trunk piston marine engine lubricating oil composition for a medium-speed four-stroke compression-ignited marine engine.

Abstract: A lubricant additive comprising an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent dispersed in a diluent comprising 10 mass % or more of a basestock containing greater than or equal to 90% saturates and less than or equal to 0.03% sulphur is blended, in a minor amount, with an oil of lubricating viscosity, in a major amount, to give a trunk piston marine engine lubricating oil composition for a medium-speed four-stroke compression-ignited marine engine.

Abstract: Trunk piston marine engine lubrication comprising a major amount of (A) an oil of lubricating viscosity that comprises an oil-soluble ester basestock, or that comprises greater than 0.1 to less than 90 mass % of an oil-soluble ester basestock and, as 50 mass % or more of the remainder of the oil of lubricating viscosity, a high saturates basestock; (B) a minor amount of a metal alkyl salicylate detergent; and (C) greater than 0.1 to less than 10 mass %, 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 composition, caused by the presence of contaminant heavy fuel oil, is prevented or inhibited.

Abstract: 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.

Abstract: A trunk piston marine engine lubricating oil composition for a medium-speed compression-ignited marine engine comprises, in a major amount, an oil of lubricating viscosity containing 50 mass % or more of a Group II basestock, and, in respective minor amounts, (A) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of 4.5 or less, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of greater than 4.5. The ratio of detergent (A) to detergent (B), both expressed as mass of active ingredient, is in the range from 0.5 to 15. The trunk piston marine engine lubricating oil composition has a TBN (using ASTM D2896) of 20 to 60.

Abstract: An oil-soluble hydrocarbyl phenol aldehyde condensate having the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms. The oil-soluble hydrocarbyl phenol aldehyde condensate has a weight average molecular weight (Mw) of 1250 to 1680, as measured by MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight) mass spectrometry.

Abstract: A lubricating oil composition having a total base number of more than 15 mg KOH/g, as determined by ASTM D2896, and including at least 40 mass % of an oil of lubricating viscosity; at least one detergent; and at least one compound of the formula (II): In formula (II), each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from the group consisting of alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y? is independently a moiety of the formula Z(O(CR2)n)yX—, wherein X is selected from the group consisting of (CR?2)z, O and S; R and R? are each independently selected from H, C1 to C6 alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR?2)z, and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, with the proviso tha

Abstract: A trunk piston marine engine lubricating oil composition for a medium-speed compression-ignited marine engine comprises, in a major amount, an oil of lubricating viscosity containing 50 mass % or more of a Group II basestock. and, in respective minor amounts, (A) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of 4.5 or less, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of greater than 4.5. The ratio of deterrent (A) to detergent (B), both expressed as mass of active ingredient, is in the range from 0.5 to 15. The trunk piston marine engine lubricating oil composition has a TBN (using ASTM D2896) of 20 to 60.

Abstract: A lubricating oil composition having a total base number of more than 15 mg KOH/g, as determined by ASTM D2896, and including at least 40 mass % of an oil of lubricating viscosity; at least one detergent; and at least one compound of the formula (II): In formula (II), each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from the group consisting of alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y? is independently a moiety of the formula Z(O(CR2)n)yX—, wherein X is selected from the group consisting of (CR?2)z, O and S; R and R? are each independently selected from H, C1 to C6 alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR?2)z, and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, with the proviso tha