| abstract |
The lubricating oil composition for a spark ignition internal combustion engine according to the present invention includes a piston having a piston ring, and is used for a spark ignition internal combustion engine in which the total tension per piston is 30 N or less. A lubricating oil composition comprising a base oil, (A) an organometallic additive containing an alkali metal and / or alkaline earth metal, and (B) an organozinc additive. The concentration of the component (A) on the basis of the total amount is 0.15% by mass or less in terms of metal content, and the concentration of the component (B) on the basis of the total amount of the lubricating oil composition is 0.15% by mass in terms of zinc content The product of the concentration (mass%) of the component (A) and the base number (mgKOH / g) of the lubricating oil composition is 1.3 or less, and the concentration (mass of the component (B) %) And the acid value (mgKOH) of the lubricating oil composition product of g) is 1.2 or less, Noack evaporation loss of the lubricating oil composition is 10 mass% or more and a kinematic viscosity at 100 ° C. is not more than 9.3 mm 2 / s As a result, deterioration of the combustion state of the ignition type internal combustion engine can be prevented. |