| 摘要 |
PROBLEM TO BE SOLVED: To obtain an engine oil composition having a combination of excellent metal corrosion-resisting performance and valve operating abrasion-proofing performance. SOLUTION: This engine oil composition is obtained by incorporating an engine base oil selected from mineral oils and synthetic oils with the following ingredients: (A) 0.01-0.1 wt.%, on a boron basis, of a boron compound derivative of alkenylsuccinimide, (B) 0.2-3 wt.% of a polysulfide, and (C) 0.01-2 wt.% of an alkylated thiadiazole and/or derivative thereof. |
