What Causes Engine Oil Leaks?
2 Answers
There are many reasons for engine oil leaks, which can directly affect a vehicle's technical performance, leading to wastage of lubricants and fuel, power loss, and environmental pollution. The main causes of engine oil leaks are as follows: 1. Excessive oil addition, high oil levels, or using the wrong oil type account for the most significant proportion of oil leak causes. 2. Uneven tightening force or loosening of various fastening nuts on the vehicle, leading to operational failure. Regular inspections are necessary to avoid such oil leak issues. 3. To save costs, some customers may opt for cheaper car parts, but poor-quality materials, inferior craftsmanship, and improper structural design are high-risk factors for oil leaks. 4. Blocked vent plugs or one-way valves can cause leaks at weak sealing points. This type of oil leak is more technical and difficult to detect without professional diagnostic tools from a 4S shop. 5. Vehicle aging is another major cause of oil leaks. Prolonged use of sealing materials leads to excessive wear, aging, deterioration, and deformation failure.
When driving, I've noticed that the most common cause of oil leaks is the deterioration or damage of the oil pan gasket, especially in older vehicles, as rubber materials tend to dry out and crack, leading to seepage. Another frequent issue is an improperly tightened or poorly sealed oil filter, which can leak if not installed correctly during an oil change. The valve cover gasket is also problematic, often shrinking under engine heat and causing leaks. Front crankshaft seal failure is another common cause of oil leakage, typically seen in high-mileage vehicles. Additionally, a loose oil filler cap or corroded oil line connections should be inspected. If oil spots are noticed under the car, prompt inspection and repair are essential to prevent severe engine wear or even failure due to insufficient lubrication. During routine maintenance, having a technician inspect the chassis using a lift can effectively prevent these issues.
