Will adding too much engine oil damage the engine?
3 Answers
Adding too much engine oil can indeed damage the engine. Excessive oil reduces the engine's output power. When the crankshaft reaches the bottom dead center during operation, it collides with the oil, increasing the crankshaft's operational resistance. As a result, drivers may notice a decrease in vehicle power during operation. An engine is a machine capable of converting other forms of energy into mechanical energy, primarily used as a power-generating device. Based on structural and functional differences, engines are categorized into: 1. External combustion engines: Fuel burns outside the engine; 2. Internal combustion engines: Fuel burns inside the engine; 3. Gas turbines: Combustion produces high-pressure gas, which is then used to rotate the turbine blades and output power.
As an experienced car enthusiast, I often see engine problems caused by overfilling engine oil. I remember helping a friend deal with a car where the oil was filled too much—the engine made strange humming noises, and blue smoke came out of the exhaust pipe. Excessive oil increases oil pressure, reduces oil pump efficiency, and causes lubrication oil to foam, preventing even coverage on parts, ultimately leading to severe wear on bearings and piston rings. The repair cost exceeded 5,000 yuan, and the owner regretted not checking the dipstick. Generally, when adding new oil, pour it in slowly and measure frequently, keeping the level safely between the Min and Max lines. Long-term overfilling can cause internal seal leaks, reduced fuel efficiency, and even overheating issues. It's recommended to start the engine and run it for a few minutes after each oil change, then recheck the level to avoid temporary overfilling. If you accidentally add too much, buy a manual oil extraction tool to remove some or drive to a repair shop for drainage—never delay handling it to prevent permanent engine damage.
As an average car owner, I accidentally overfilled the engine oil during a DIY oil change last year. Initially, I didn't notice anything wrong, but while driving, the engine suddenly became as noisy as drumming, and acceleration became sluggish. After consulting with a car-savvy neighbor, I learned that excess oil causes the oil pump to draw in air, creating foam that reduces lubrication protection and increases friction between components, leading to overheating. Later, I checked with the dipstick and found it was overfilled by half an inch. I promptly used a suction tube to remove the excess oil, which resolved the issue. Now, I always remember to follow the oil change manual's specified amount, typically around 4-5 liters depending on the car model. The downsides of overfilling oil include increased fuel consumption, noticeable smoke emission, and potential damage to the crankcase. I've made it a habit to check the dipstick before every startup and to pay attention to any unusual engine noises to prevent major problems.
