1. What is a lubricating oil?

        In general, it is a substance that reduces friction when placed between two surfaces withrelative motion. There are lubricants with different grades and viscosities, although their functions have a lot of similarities as they:Reduce friction between two metal surfaces.Protect mechanical components from wear and corrosion. Clean and cool engines.Act as a sealant between the segments/pistons and jackets in order to prevent gas leaksinside the combustion chamber.