🔍 Key Concepts

• Look closely at where label 1 is pointing in the cylinder head area and which valve train parts are connected to it (valve stem, rocker arm, pushrod). • Remember the different flow paths: fresh air/fuel mixture or scavenging air versus hot exhaust gas and note their colors in the diagram legend. • Understand what a valve spring does in a four‑stroke diesel: it keeps a specific valve (inlet or exhaust) seated until the cam opens it.

💭 Think About

• Is label 1 attached to the mechanism that opens toward the intake/scavenging air port, or the one that opens toward the exhaust manifold? • How does the color‑coding in the illustration (exhaust vs scavenging air) help you decide whether this spring is on the intake or exhaust side? • Which option does NOT describe a spring at all, and which option sounds like a general fastener feature rather than a specific diesel component?

✅ Before You Answer

• Verify which side of the head is the exhaust passage (use the color legend and gas flow arrows). • Confirm that the part at label 1 is coiled around the valve stem under a retainer, typical of valve springs. • Eliminate any answer choices that do not match the shape and function of a helical spring acting on a valve.