What are the consequences of excessive engine oil?
2 Answers
First, it can cause power loss and oil leakage in the car. Excessive engine oil increases internal oil pressure, leading to poor operation of some engine components, which cannot provide sufficient power to the vehicle. Moreover, the increased oil pressure may damage oil seals, resulting in oil leakage. Below are relevant details: Oil burning: When there is excessive oil in the engine, the crankshaft's rotation will churn the oil, creating a large number of bubbles. These bubbles are carried into the combustion chamber through the ventilation system and burned, leading to the so-called oil burning phenomenon. Furthermore, these bubbles may also cause wear to the cylinders and pistons. Catalytic converter clogging: Excessive oil burning produces certain residues that are not expelled from the vehicle but accumulate inside the catalytic converter. Since this is not easily noticeable under normal circumstances, by the time it accumulates to a certain extent, the catalytic converter may be beyond repair.
Having driven for decades, I can attest that overfilling engine oil can cause serious trouble. When the oil level is too high, the pressure inside the engine surges dramatically, forcing oil to seep out through seals and creating messy leaks that are a nuisance to clean up. More critically, excessive crankshaft agitation generates air bubbles, turning the oil into a foamy substance that loses its lubricating properties. This leads to increased friction between components, accelerated wear, louder engine noise, and even potential seizure. The vehicle may feel sluggish while consuming significantly more fuel. Oil might also enter the combustion chamber, producing unpleasant blue exhaust smoke and fouling spark plugs, which raises the risk of sudden engine stalling during operation. Prolonged overfilling severely shortens engine lifespan, potentially resulting in thousands in repair costs. I've developed the habit of precisely measuring the oil level with a dipstick before every oil change, never casually pouring extra.
