What are the causes of engine bearing seizure?
2 Answers
Engine bearing seizure can be caused by insufficient oil pressure, clogged oil passages with debris, low engine operating temperature, or excessive temperature. Insufficient oil pressure: If the oil pump gears are severely worn, the oil pumping pressure may be inadequate. Alternatively, oil pipe leaks or insufficient oil levels can reduce oil pressure, making it difficult to supply oil to designated lubrication points, resulting in dry friction and bearing seizure. Clogged oil passages with debris: Dirty oil, clogged oil filters, or poor oil supply can prevent oil from circulating between the bearings for lubrication, increasing friction and leading to bearing seizure. Low engine operating temperature: Especially in winter without proper preheating, the oil remains viscous and cannot circulate effectively, reducing lubrication. If the throttle is suddenly floored, the temperature between the bearings rises rapidly, causing surface burning and bearing seizure. Excessive temperature: Lack of oil or insufficient oil, fuel mixing with oil, or water mixing with oil can thin the oil. Alternatively, coolant leaks, water shortage, or fan failure can cause the engine to overheat, leading to bearing seizure.
I've been in auto repair for over a decade. Simply put, engine bearing seizure means the bearings are burnt out. The most common cause is insufficient or deteriorated engine oil, leading to poor lubrication. When the oil film breaks down, friction generates heat, causing direct dry contact between bearings and crankshaft - grooves can be scraped instantly. Secondly, low oil pressure from faulty oil pumps or leaking pipelines prevents oil from reaching critical components. Other factors include clogged filters contaminating oil passages, engine overheating degrading oil quality, or overload driving subjecting bearings to excessive pressure. For prevention, I always remind owners to change oil regularly and monitor oil pressure gauges - don't wait for abnormal noises before fixing. Once bearings seize, the entire engine may be ruined with prohibitively high repair costs. Consistent maintenance saves big money.
