What are the causes of cylinder scuffing in an engine?
2 Answers
The causes of cylinder scuffing in an engine are: 1. Engine overheating due to coolant system leakage, water shortage, and failure to replenish in time; 2. Piston ring fracture, scratching the cylinder wall; 3. Piston pin circlip detachment, scratching the cylinder wall; 4. Piston rings stuck in the grooves due to carbon deposits, losing sealing function; 5. Piston pin protrusion, scratching the cylinder wall; 6. Foreign objects entering the cylinder; 7. Excessive small clearance between the piston and cylinder wall; 8. Overly tight piston pin assembly causing piston deformation; 9. Severe piston thermal deformation or melting at the top; 10. Prolonged high-speed or overload operation of the engine.
As a seasoned mechanic with years of experience, I've seen many cases of engine cylinder scuffing, most of which are closely related to lubrication system failures. Problems with oil supply can be due to insufficient oil volume or a malfunctioning oil pump, or poor-quality or contaminated oil. Increased friction leads to the piston and cylinder wall seizing up. Additionally, engine overheating often causes cylinder scuffing—coolant leaks or a broken fan reduce the thermal expansion gap of the metal, leading to issues. I've encountered cases where owners neglected maintenance, like failing to replace a clogged oil filter, resulting in insufficient oil pressure and cylinder scuffing. It's advisable to regularly check oil levels and viscosity and use high-quality oil. A dirty air filter is also problematic, as dust entering the cylinder increases friction. If the water temperature is abnormal, stop and inspect promptly to avoid major trouble.
