Reasons for contamination of lubricating oil during use

During engine operation, some of the issues that arise can cause certain contamination and impact on the lubrication system, thereby affecting engine performance, impairing the driving experience, and in severe cases, necessitating repairs. The causes of some contamination and their effects on the lubrication system are summarized as follows:

1. Contamination of water or coolant

Causes of contamination: 1. Condensation due to low-temperature operation: Cooling water temperature too low, poor crankcase ventilation, prolonged engine idling, frequent starts and stops; 2. Poor piston sealing, severe blow-by: Piston ring or cylinder liner wear, piston ring sticking or damage, blocked exhaust system.

Impact on lubricating oil and engine operation: 1. Increase: Low-temperature deposits (sludge), oil emulsification, rust and corrosion; 2. Decrease: Oil stability, oil detergency and dispersancy.

2. Fuel dilution oil contamination

Pollution causes: 1. For gasoline engine oil: rich mixture, throttle malfunction, piston ring sticking or damage, spark plug carbon buildup, ignition failure, excessive blow-by; 2. For diesel engine oil: diesel circuit obstruction, enlarged injector nozzle size, injector dripping, poor atomization quality, exhaust system blockage, piston ring sticking or damage.

Impact on lubricating oil and engine operation: 1. Increase: engine wear, varnish deposits; 2. Decrease: viscosity, flash point, oil stability.

3. Contamination of engine oil by dust and sand particles

Causes of contamination: 1. Inhaling dust: low efficiency of air filter, air leakage in the intake system, no filter at the crankcase breather port; 2. Dirty oil or fuel: fuel contamination, low efficiency of fuel filter, oil contamination, low efficiency of oil filter.

Impact on lubricating oil and engine operation: Increase: abrasive wear, deposits, oil foaming, clogging of air filters and fuel filters.

4. Contamination of engine oil by metal particles

Cause of contamination: Excessive wear: Inhaling dust, poor maintenance of air filters, engine oil lubricity not meeting engine requirements, low efficiency of oil filters;

Impact on lubricating oil and engine operation increases: catalytic oxidation of oil, formation of deposits, abrasive wear, bearing embedment.

5. Contamination of engine oil by soot carbonaceous matter

Pollution causes: Diesel engine oil: Rich fuel and lean gas leading to poor combustion, excessive fuel supply, blocked intake system, poor technical condition of fuel injectors, blow-by gas;

Increased impact on lubricating oil and engine operation: darkening of oil color, changes in viscosity, formation of deposits, and clogging of oil filters.

6. Other Pollution Causes

Cause of contamination: excessive water content in the engine oil, severe blow-by gas, and intensified oxidation of the oil.

Impact on lubricating oil and engine operation: Increase: engine deposits, wear;