What Causes Engine Oil Filter Leakage?
3 Answers
Engine oil filter leakage can be caused by: a ruptured sealing gasket, improper tightening during installation, or over-tightening leading to housing damage. The engine oil filter, also known as the oil element, comes in two types: full-flow and bypass. The full-flow filter is connected in series between the oil pump and the main oil gallery, filtering all lubricating oil entering the main gallery. The bypass filter is connected in parallel with the main oil gallery, filtering only a portion of the oil delivered by the pump. The working principle is: during engine operation, contaminated oil enters the filter through the inlet on the baseplate assembly. After passing the check valve, the oil waits outside the filter paper for filtration. Under oil pressure, the oil continuously passes through the filter paper into the central tube, leaving contaminants trapped on the paper.
I often do car maintenance myself and have encountered oil filter leaks a few times, mainly due to installation issues. For example, last time I changed the oil, I didn't tighten the filter enough, and the old oil wasn't completely cleaned off the sealing gasket. After a few days of driving, I noticed oil drops on the ground, and sure enough, it was leaking. Sometimes, the filter itself is of poor quality or gets cracked from impact, making it more prone to leaks under high oil pressure. My advice when installing a new filter is to be meticulous: first, wipe the connection area clean with a cloth, align the gasket and tighten it properly without over-torquing, as excessive force can damage the threads. If you're not confident, it's best to visit a professional shop. Oil leaks can lead to oil shortages, engine overheating, or even require a major overhaul. Regularly check under your car when parked to catch issues early and save yourself from bigger problems.
I found that an oil filter leak can be quite dangerous. Once, my car's filter came loose and leaked, causing the oil level to gradually drop. If ignored, the engine could suddenly seize and destroy the car. The causes are usually improper installation or aging/damage to the filter. In my experience, oil pressure fluctuations can worsen the leak. If you notice a leak, it's best to stop immediately and inspect the location—simply wipe off surface oil to observe the source, but avoid tampering to prevent making it worse. I recommend taking it to a reliable repair shop; they have the tools to tighten it precisely and prevent hazards. Oil leaks also pollute the environment, so we must prioritize driving safety—don’t let small issues turn into big disasters.
