Proper lubrication of all the moving parts is extremely important in engine operation. The function of the engine lubrication system is lubricating all friction surfaces of the engine parts, to reduce friction and wear between moving parts of the engine, to take away surfaces heat as well as debris left by worn part and to improve the sealing of cylinder. There are meanwhile many functions in lubricating system, such as, lubricating, radiating, cleaning, anticorrosion, sealing, vibration reduction and hydraulic pressure.
The types of diesel engine lubrication system components are mainly as follows: oil pan, oil pump, pressure limiting valve, oil passage, oil filter and oil radiator.