🔍 Key Concepts

• piston rings and their function in sealing combustion pressure • the pathway between combustion chamber and crankcase in a typical diesel • difference between compression sealing parts and components that mainly provide support or guidance

💭 Think About

• Which component is specifically designed to keep high-pressure combustion gases from leaking past the piston into the crankcase? • Do wrist pins, liner seals, or sealing rings normally form the main gas-tight seal for combustion, or do they serve other purposes? • If combustion gases leak into the crankcase, through what part of the piston/cylinder assembly must they pass first?

✅ Before You Answer

• Identify which choice is the primary gas-sealing element between piston and cylinder during compression and power strokes • Confirm which parts are mainly for mechanical support (rather than gas sealing) • Visualize a cross-section of a diesel engine and trace the route from combustion chamber to crankcase