The base oil is composed of a base stock or a blend of a number of base stocks. As the base oil alone cannot provide all of the lubricating oil functions required in modern engines, the additive package has evolved to play an increasingly important role in the oil formulation.

Serving as a hydraulic media in components such as HEUI fuel systems.Įngine lubricants consist of a base oil (typically 75 - 83%), viscosity modifier (5 - 8%) and an additive package (12 - 18%).

Keeping seals lubricated and controlling swelling to prevent leakage due to seal failure and.

Cleaning pistons and preventing sludge build-up on internal surfaces,.

Corrosion prevention due to acids and moisture,.

Friction reduction of boundary and hydrodynamically lubricated components,.

Wear reduction of components such as bearings, pistons, piston rings, cylinder liners and the valve train,.

Lubricating oils perform a number of important functions in the diesel engine: A common way to help determine appropriate oil drain intervals is through used oil analysis. During use, oil can become contaminated by soot, unburned fuel, metallic particles and other contaminants. Oil viscosity must be selected to ensure that hydrodynamic lubrication will occur where and when it is needed.

The viscosity of engine oil is its most important property. Abstract: Diesel engine lubricants are composed of base oil, viscosity modifier and an additive package that may include antioxidants, pour point depressants, detergents and dispersants.

Testing viscosity of oil