| 摘要 |
PROBLEM TO BE SOLVED: To increase the exchange period of time for a crank case lubricant in a spark ignition engine. SOLUTION: There is provided a method of increasing the exchange period of time for (A) a crank case lubricant in the spark ignition engine that involves treating a motion surface with group IV raw oils that are one or more kinds of poly-α-olefins having a viscosity of 2-20 cSt at 100°C or a large amount of a raw oil having a lubricant viscosity containing a mixture thereof, defined by API 1509, in the range of 40 mass% to 80 mass%, or with (B) an SAE 10W-X or SAE 5W-X or SAE 0W-X crank case lubricating oil (wherein, X is 20, 30 or 40) containing one or more ashless dispersants and one or more kinds of metal detergents, and also two or more kinds of additive components. COPYRIGHT: (C)2009,JPO&INPIT |
