🔍 Key Concepts

• Compare camshaft speed to crankshaft speed in two-stroke vs four-stroke diesel engines. • Look closely at the cylinder liner and surrounding cooling space to decide if it is a wet liner or dry liner. • Use the piston position and which passages/valves are open to identify the engine stroke being shown (intake, compression, power, or exhaust).

💭 Think About

• From the illustration, does this engine complete its full cycle in one crankshaft revolution or two? How does that affect camshaft speed? • Do you see cooling water in direct contact with the outside of the liner, or is the liner backed solidly by the block metal? • Is the piston near top or bottom dead center, and which path (to the turbocharger or from the blower/intake) is open at that instant?

✅ Before You Answer

• Verify whether intake ports in the cylinder wall are being uncovered by the piston (a clue to a uniflow two-stroke). • Check if there is a water space surrounding the outer surface of the liner with sealing rings at the lower end (indicating a wet liner). • Confirm which valve or ports are open and the direction of gas flow to decide whether the stroke shown can be the end of the exhaust stroke.