What are the symptoms of engine cylinder liner damage?
3 Answers
Cylinder liner damage manifests in two forms: wear on the cylinder mirror surface and corrosion on the outer wall of the cylinder liner. Here are the causes of these two symptoms: 1. Wear on the cylinder mirror surface: This is caused by sulfur and other impurities in the fuel or frequent cold starts. When the cylinder mirror surface is worn, loose tiny pores can be observed on the upper part of the mirror surface. 2. Corrosion on the outer wall of the cylinder liner: This is mainly caused by chemical reactions, electrochemical effects, liquid impact, and mechanical vibrations. One of the more severe forms is cavitation, which appears as honeycomb-like clusters of small pits on the pressure-bearing side of the piston or the opposite outer wall of the cylinder liner.
Anyone who's driven a car knows that when the cylinder liner fails, the vehicle becomes sluggish. Pressing the accelerator gives a noticeable lack of power, and acceleration becomes as slow as an old ox cart. You can even hear metallic clanking sounds from the engine bay, especially during cold starts when the noise is particularly loud. The most frustrating part is seeing blue smoke from the exhaust pipe, requiring frequent oil top-ups every few hundred kilometers. The temperature gauge needle often surges toward the red zone, and coolant consumption becomes alarmingly high. Once during a long trip, I discovered a milky white substance under the oil cap—that's when I realized the cracked cylinder liner had allowed coolant to mix with the engine oil. If not addressed promptly, the pistons could even fuse to the cylinder walls.
Cylinder liner damage essentially means the failure of cylinder sealing. When air pressure leaks through cracks or wear, the engine's compression ratio collapses. As the piston moves up and down, air leakage occurs, leading to noticeable unstable idle speed and steering wheel vibration. Oil seeping into the combustion chamber generates excessive carbon deposits, resulting in blue smoke from the exhaust pipe and irritating fumes. If the cylinder liner deforms, it's even worse—piston ring seizure causes sharp friction sounds, especially audible when driving on the highway with the window down. Once, I encountered unexplained coolant loss and discovered cracks in the cylinder liner allowed coolant to flow into the cylinder. The mixture burned, producing white smoke and even rusting the spark plugs. Fixing such chain reactions costs at least several thousand yuan.
