Lubrication system — general description (Mercedes-Benz E-Class W210)

Without sufficient lubrication, the engine stops working within a few minutes. The thinnest oil film protects dynamic connections and engine mechanisms from destructive friction, such as pistons and piston pins, cylinder running surfaces, connecting rods and main bearings of the crankshaft, and timing mechanism components.

To ensure the constant presence of an oil film in the contacting parts, the oil circulates through the pipes and channels when the engine is running. The oil pump takes oil from the oil pan and distributes it through the channels of the lubrication system to the lubrication points. For cleaning, the engine oil passes through an oil filter, which cleans it from wear products and other foreign inclusions. Cleaning is carried out until the microscopic pores of the oil filter are completely clogged with wear products.

When the filter is clogged, the safety valve starts working, which opens the auxiliary circulation channel at a certain pressure. Unfiltered oil primarily causes rapid wear of the bearings. From the filter, the lubricant gets through the holes in the cylinder block to the bearings of the crankshaft, connecting rod and valve mechanism in the cylinder head. Due to the inclined position of the engine, it can flow from the lowest point of the cylinder head through the hole without additional heating into the oil bath. The cylinder walls and piston pins are lubricated with oil entering through the connecting rods.

Another important function of oil is to remove heat from lubricated surfaces. The piston bottoms are sprayed with oil from below, which is supplied not for lubrication, but for cooling.

(Publication reprinted from this resource: «MercedesMAN.ru»)