What Happens If Engine Oil Is Not Changed for a Long Time?
3 Answers
Not changing the engine oil for a long time will accelerate engine wear and affect engine performance, significantly reducing its sealing, lubrication, and cooling effects. The impurities in the oil will wear down internal components, thereby shortening the engine's lifespan and increasing the likelihood of malfunctions, which can pose safety hazards. Engine oil is often referred to as the 'blood' of the engine, as it plays crucial roles in cleaning, sealing, heat dissipation, lubrication, cushioning, and rust prevention within the engine. Over time, engine oil becomes thinner and deteriorates. Typically, full synthetic oil should be changed every 10,000 kilometers or once a year, semi-synthetic oil every 7,500 kilometers or every 7-8 months, and mineral oil every 5,000 kilometers or every 6 months.
Oh, I've seen many car owners who think their cars are running fine and neglect to change the oil on time. Honestly, this is no small matter. Inside the engine, components like gears and pistons are constantly rubbing against each other, relying entirely on the oil for lubrication and protection. Over time, the oil turns black and thick, filled with tiny wear particles, sticky like syrup. These contaminants circulate inside the engine, grinding against precision parts like sand, accelerating wear and tear. Not only does the lubrication effectiveness drop significantly, but thick sludge buildup also causes serious cooling issues. After prolonged use, the engine starts roaring like a tractor and may even overheat, triggering warnings. If ignored, the entire engine could fail prematurely, and the repair costs would far exceed the price of regular oil changes. I once met a truck driver who saved money by skipping a few oil changes, only to have the engine seize up and break down on the road—a costly lesson indeed. So, as the old saying goes, regular oil changes keep the car running long and strong.
Delaying oil changes for a long time directly leads to major lubrication issues in the engine. Fresh oil is golden, clear, and provides excellent lubrication, while old oil becomes thick, dark, and loses its fluidity. It flows poorly in areas that require lubrication, akin to coating precision components like bearings and piston rings with sticky glue, hindering smooth operation. Metal parts experience dry or semi-dry friction, causing temperatures to rise rapidly. High temperatures not only accelerate oil degradation but also cause rubber seals to harden and crack faster. For instance, if valve stem seals age, they may start burning oil, resulting in blue smoke from the exhaust pipe. Cooling issues may follow, potentially triggering the engine overheating warning. Even worse, accumulated sludge can clog the crankcase ventilation system, leading to excessive pressure that may force oil out through weak seals, causing leaks. The cost of repairing an engine once could cover numerous oil changes. By the time problems arise, it’s no longer just about changing the oil.
