An Empirical Study of Cylinder Kit Hardware Affects on Oil Consumption in the Cummins NTC-400 892052
The combined and independent influences of cylinder liner surface texture, and piston ring performance on oil consumption in the Cummins NTC-400 Test was examined via pre and post test hardware measurements. In order to evaluate these relationships on a per cylinder basis the first correlation study examined the relationship between average heavy crownland carbon (HCLC) piston deposits and average measured oil consumption.
All parts used in the comparative analysis were run in a laboratory under NTC-400 Test conditions, and each test used the same lubricant. The data presented was obtained from numerous cylinder kits representing a total combined run time of about 10,000 hours. After a significant correlation between HCLC and measured oil consumption was determined, various hardware measurements were checked for correlation to HCLC. With HCLC serving as an estimate of relative oil consumption on a per cylinder basis, all kit measurements were compared with the corresponding HCLC deposit value for that cylinder. These comparisons did reveal some interesting relationships.
Each correlation exercise is preceded by a hypothesis of the relationship between the measured variable and its influence on oil consumption. Both single and multiple correlation regressions were utilized. While the correlation analysis did not reveal any absolute relationships this study did uncover some parameters of hardware configuration that merit further analysis.