1.1Â This test method2 evaluates the performance of lubricants intended for use in two-stroke-cycle spark-ignition gasoline engines that are prone to preignition.
5.1Â Two-stroke-cycle gasoline engines are generally more prone to preignition than are four-stroke-cycle engines due to the absence of the internal cooling that takes place during the induction stroke of the four-stroke-cycle engines. Preignition can lead to major piston damage, either directly due to localized overheating or as the result of preignition-induced detonation. Some lubricant additives that are widely used in four-stroke-cycle gasoline engine oils are known to increase the probability of preignition in gasoline two-stroke-cycle engines. This procedure is used to determine the tendency of an oil to induce preignition in both water-cooled and air-cooled two-stroke-cycle gasoline engines.
| SDO | ASTM: ASTM International |
| Document Number | D4858 |
| Publication Date | June 15, 2013 |
| Language | en - English |
| Page Count | 9 |
| Revision Level | 13 |
| Supercedes | |
| Committee | D02.B0 |