| abstract |
A cylinder lubricating oil composition for crosshead diesel engines, which comprises (1) 2.0 to 5.5 mass% of sulfuric acid ash, 15 to 45mgKOH/g of base number, and 262 ℃ or higher of autoignition temperature. A cylinder lubricating oil composition for crosshead diesel engines, which comprises a lubricating oil base oil, (B) a Ca sulfonate detergent having a base number of 10mgKOH/g or more and less than 60mgKOH/g, (C) a Ca phenate detergent having a base number of 55 to 200mgKOH/g, (D ') an amine antioxidant and (E') zinc dithiophosphate, and has a base number of 15mgKOH/g or more and less than 120 mgKOH/g. |