Restoration of vintage vehicles is becoming more and more popular nowadays. Conditions of usage and operation changed throughout recent years, factory recommended lubricants and fuels are no longer available. The usage of improper lubricants can lead to severe engine damages. The aim of our research is to conduct the analytical and tribological investigation of the lubricant used in a Triumph SC 1300 type four-stroke gasoline engine assembled with two carburetors. Our further task is to conduct analytical and tribological investigation of engine oil that we infused with MoS2 to compare it with the oil in accordance with factory parameters after defined test operation. After the analysis and evaluation of results we serve with recommendations in connection with the given engine to operate it with the most appropriate engine oil regarding operation conditions.

In recent times, many specially engineered diesel engines built in the 1980s are still used in different areas, for which the suggested engine oils are no longer available. These engines are operated reliably in military combat vehicles, electricity generators, and tracked machinery, thus it is essential to examine what engine oils are suitable for their operating conditions and may be used as their engine oil. The aim of our research is to conduct the tribological examination of an oil sample taken from a V-6M type naturally aspirated Diesel engine and the oil prescribed by the manufacturer. After evaluating the results, we determine which type of oil is applicable in the engine to achieve safe operation and a long lifetime.