| 摘要 |
PROBLEM TO BE SOLVED: To provide a system lubricating oil composition for crosshead diesel engines which causes less deposit formation even when a base oil having a high content of unsaturated hydrocarbons is used and has excellent high-temperature cleanness and coking resistance, or heating resistance.SOLUTION: A system lubricating oil composition for crosshead diesel engines consists of (B) a metal type cleaner, (C) zinc dithiophosphate and (D) an amine type antioxidant, bended in (A) a base oil of a kinematic viscosity at 100°C of 8.2-12.6 mm/s and a content of saturated hydrocarbons of 90 mass% or higher. The composition has a content of (D) the amine type antioxidant of 0.3 mass% or higher, relative to the total amount of the composition, a base number of 6.5 mgKOH/g or greater and a phosphorus content of 200-1,000 mass ppm. |
