What Does Cylinder Scuffing Mean?
3 Answers
Cylinder scuffing refers to an impact failure between the piston and cylinder liner in an internal combustion engine. The causes of cylinder scuffing include: 1. Severe lack of lubrication oil; 2. Drastic changes in the thermal expansion coefficient of metal objects; 3. Excessive mechanical lubrication clearance between the piston and cylinder wall; 4. Poor quality cylinder gasket with insufficient surface flatness; 5. Improper driving habits, such as long-term aggressive driving. Symptoms of cylinder scuffing include: 1. Engine weakness during driving, difficulty in acceleration, and air leakage sounds at the joint between the cylinder head and cylinder block; 2. One or two cylinders not working, with bubbles appearing at the radiator filler opening; 3. Milky white engine oil when checking with the dipstick; 4. Continuous water droplets flowing from the exhaust pipe.
A blown head gasket is essentially a problem with the engine's cylinder head gasket, where the sealing effect deteriorates, causing water and engine oil to mix. That time I was driving on the highway when the water temperature gauge maxed out, it nearly scared me to death. Upon opening the hood, I found the engine oil emulsified into a coffee color—a classic case of water mixing with the oil. The root cause was prolonged high temperatures leading to metal deformation and the cylinder head gasket being burnt. If not addressed promptly, it can wear down the cylinder walls and even lead to engine seizure and total failure. If you notice abnormal water temperature, loss of power, or white smoke from the exhaust pipe, it's advised to pull over immediately and turn off the engine. This is definitely not something to tough out. Towing it to a repair shop to tighten the cylinder head gasket should suffice, but if the piston top is deformed, a major engine overhaul will be necessary.
When the cylinder head gasket in the middle of the engine blows out, it's called a blown head gasket. The gasket itself is made of steel sheets wrapped with asbestos, acting like a sandwich layer to separate coolant and engine oil. However, if the engine overheats or the cylinder head bolts become loose, high-pressure combustion gases can breach this barrier. Last time my car had this issue, I noticed milky white foam under the oil cap and unexplained coolant loss. The mechanic diagnosed it as a failed head gasket seal, causing cross-contamination between coolant and oil passages. During repairs, the entire engine had to be hoisted out to resurface the cylinder head mating surface and reinstall it, while also checking for any scoring marks on the cylinder walls.
