🔍 Key Concepts

• Cylinder lubrication and wear mechanisms in two- and four-stroke diesel engines • Relationship between fuel quality, combustion quality, and liner surface condition • How scavenge air, lube oil viscosity, and compression ratio each affect engine performance vs. wear

💭 Think About

• For each option, ask: does this primarily affect combustion performance or does it directly influence metal-to-metal contact and protective oil film on the liner? • Consider which factor most strongly controls the protective layer between piston rings and liner surface during operation. • Think about what happens to the liner surface when conditions cause poor lubrication, deposits, or corrosion—which option changes that most directly?

✅ Before You Answer

• Identify which choice most directly affects the condition and effectiveness of the oil film between rings and liner. • Separate factors that mainly influence engine efficiency/power from those that directly affect surface wear and scuffing. • Verify which item, if changed slightly, would most quickly show up as increased liner/ring wear in maintenance reports.