What Are the Causes of Abnormal Engine Oil Consumption?

[LeSadie]

Reasons for abnormal engine oil consumption: 1. Oil leakage in the oil circuit; 2. Damage to the crankshaft oil seal; 3. Excessive oil pressure leading to seal gasket failure; 4. Rupture of sealing rings; 5. Excessive wear of the valve guide; 6. Breakage of the valve guide. If the valve guide breaks, oil will enter the combustion chamber through the gap between the valve stem and the valve guide, participating in combustion. Failure of the crankcase ventilation valve causes oil to enter the combustion chamber along with the gases in the crankcase. Blockage of the crankcase ventilation port increases the pressure inside the crankcase, leading to a higher amount of oil entering, which is also one of the factors for excessive oil consumption. When the engine operates at high speeds, the amount of oil splashed onto the cylinder walls increases due to inertia, and the effectiveness of the oil ring in controlling oil decreases during high-speed sliding, allowing oil to enter the combustion chamber.