Which is more severe, engine bearing seizure or cylinder scuffing?
4 Answers
Both engine bearing seizure and cylinder scuffing are serious issues. If the quality of the lubricating oil is poor, bearing seizure may occur earlier than cylinder scuffing. Generally, cylinder scuffing can be caused by improper assembly after an overhaul. Vehicle engines and other components are complex and precise, and a complete disassembly and overhaul is a significant event for the engine. Any improper assembly or clearance during the repair process can lead to cylinder scuffing. The use of counterfeit air filters can easily cause excessive abrasive wear in the engine, leading to cylinder scuffing. Below is additional information: Root cause: The root cause is that the friction surface of the diesel engine's bearing cannot obtain sufficient lubricating oil to form an oil film for lubrication, or the oil itself has quality issues, such as poor load-bearing capacity and high-temperature resistance. It is important to ensure the quality of the oil. Incorrect torque: Incorrect torque during the installation of the main bearing, if too tight, can make it difficult to form an effective oil film. Always use a specialized torque wrench.
Which is more serious, engine bearing failure or cylinder scoring? I think cylinder scoring is more troublesome. Bearing failure, commonly known as crankshaft bearing damage, may be caused by insufficient oil or poor lubrication. After the bearing burns out, the engine will produce abnormal noises and vibrations, but timely replacement of the bearing can solve the issue, costing a few hundred to around a thousand yuan. Cylinder scoring, on the other hand, involves scratches on the cylinder wall, which may be caused by stuck piston rings or overheating. In this case, the engine might emit smoke and experience a drop in power. Repairing it requires disassembling the cylinder block, boring the cylinder, or even replacing the entire block, costing at least several thousand yuan or even over ten thousand. Both issues are dangerous, but cylinder scoring affects the core components, requires more time and money to repair, and may shorten the engine's lifespan. Preventive measures include regular oil changes, avoiding excessive speeding, and maintaining normal engine temperature to reduce the occurrence of such failures. In short, if you notice any abnormal noises, stop the car and inspect it as soon as possible.
From my decades of driving experience, cylinder scoring is far more severe than bearing wear. When bearing wear occurs, the noise from the worn bearings is loud, but repairs are relatively quicker, mainly involving part replacement. My friend spent just 800 yuan last time to fix it. Cylinder scoring, however, is a different story. Once the cylinder walls are scratched, the car will be out of commission for several days, and mechanics have to disassemble the entire engine block for repair or replacement—not only costly but also disruptive to daily use. Last year, I encountered cylinder scoring and spent over 5,000 yuan on repairs, nearly totaling the engine. The critical issue with cylinder scoring is that the problem is deeply internal, often triggering chain reactions like piston damage or severe oil leaks. For prevention, I recommend regularly checking the cooling system to prevent engine overheating and sticking to maintenance schedules, especially frequent oil and filter changes, to nip problems in the bud. For safety, never ignore abnormal noises while driving—address them promptly.
Among engine problems, cylinder scuffing is more severe. Bearing failure (commonly referred to as "pulling a bearing") is simpler to repair, while cylinder scuffing involves damage to the cylinder walls, making the repair more complex and costly. Cylinder scuffing poses a higher risk, leading to engine power loss and smoke emission. Repairs require cylinder disassembly, with costs starting from several thousand. Prevention methods: Pay attention to oil level and cooling.
