How to Deal with Excessive Engine Oil in a Car?
4 Answers
Methods for handling excessive engine oil in a car are: 1. Drain a portion of the oil from the oil pan's drain port. Ensure the engine temperature has cooled down before draining to avoid burns; 2. Use a syringe and a plastic tube (such as those used for IV drips) to extract the excess oil. Medical plastic tubes with measurement markings can be used for easy reference. Consequences of excessive engine oil include: 1. Increased engine operating resistance. Overfilling oil may cause the crankshaft to come into contact with the oil, generating significant resistance during high-speed operation and affecting engine performance; 2. Carbon buildup and contamination of the catalytic converter. Some additives in the oil, when burned, can enter the catalytic converter and reduce its conversion efficiency.
After the last maintenance, I noticed the engine sound was muffled. Upon checking the dipstick, I found the oil level was two centimeters above the maximum mark. Excessive oil can increase crankshaft stirring resistance, leading to a surge in fuel consumption, and worst of all, it may cause oil leaks due to high pressure rupturing the seals. When handling it myself, I first let the car cool for half an hour, then used an infusion tube and a syringe to slowly extract the excess oil from the dipstick hole, checking the oil level while extracting. I stopped when the level reached the middle of the marked range, extracting about half a soda bottle's worth. After finishing, remember to clean any spilled oil to prevent corrosion of the pipelines. If you lack the tools or the excess is too much, it's safest to drive directly to a repair shop—they have professional oil extractors for higher efficiency. Never continue driving just to save trouble.
I remember my cousin's car had 6 liters of engine oil added, and it was smoking blue like a tractor. Adding too much oil can accelerate seal aging, and severe foaming can lead to poor lubrication and engine damage. The solution depends on the situation: if you just added too much, drain some by loosening the drain plug when the engine is cold, and carefully monitor the dipstick to avoid over-draining; if it's been driven for a few days, use a vacuum pump to extract the excess—never restart the engine. If you're doing it yourself, prepare a large syringe with a hose to extract oil from the dipstick tube, checking the oil level every 200 ml. After extraction, drive 3-5 km and recheck to ensure the oil level is between the upper and lower marks on the dipstick. It's also a good idea to check if the oil has emulsified or deteriorated.
Exceeding the oil level by 1 cm poses risks, most commonly due to technician errors during maintenance or overfilling by oneself. My advice: If the overfill is minor and you have the proper tools, place a clean container under the drain bolt, loosen it half a turn to slowly release oil, and monitor the flow to avoid it being too fast. For significant overfills or if you lack tools, visit a professional shop—they can use vacuum equipment to extract the excess in just five minutes. Always wear corrosion-resistant gloves during the process, and store waste oil in a sealed container for recycling. After completing the task, run the engine for three minutes before turning it off to check the oil level, as this ensures the most accurate measurement.
