Engine Oil Contamination: Causes and Impact on Additive Efficiency

In recent years, there has been an increasing demand in the commercial market to prolong the service life of engine oil. Oil contamination is one of the most important factors that influence friction, wear and which continuously accelerates oil degradation. The main contaminants in diesel engine oil are soot and water. The engine oil with a high level of soot causes an increase in oil drain interval to minimise the effect of hard soot particles on contact surfaces. Water is also a destructive contaminant that affects engine oil’s physical and chemical stability. Many studies have been conducted on the effects of oil contaminants on oil performance, however the effects of oil contamination on additives and oil degradation are not fully understood yet. Engine oil additives have been widely used to enhance oil performance, reduce the effect of oil contamination and extend the lifespan of engine oil. Thus, the main focus of this study is to investigate the impact of soot and water on additives and the bulk oil and then replenish the influenced additives to regain the tribological performance of engine oil.