| 摘要 |
PROBLEM TO BE SOLVED: To obtain an engine oil composition desirable for alcohol fuel engines by combining an organomolybdenum compound with an aryl zinc dithiophosphate, a metal cleaner and an ashless dispersant. SOLUTION: This composition comprises a lubricating base oil, a molybdenum compound selected from among a sulfided oxymolybdenum dithiocarbamate represented by formula I (wherein R<1> to R<4> are each a hydrocarbon group, and X<1> to X<4> are each O or S), a sulfided oxymolybdenum dithiophosphate represented by formula II (wherein R and X are as defined in formula I) and a molebdenum amine compound obtained by reacting a hexavalent molybdenum compound with an amino compound represented by the formula: R<9> -NH-R<10> , zinc dithiophosphate represented by formula III, provided at least 50wt.% of it is represented by the formula (wherein R<11> and R<12> are alkylaryl groups), a metal cleaner selected from among a metal sulfinate, a metal phenate and a metal salicylate, and an asheless dispersant. |
