🔍 Key Concepts

• Piston ring movement during the engine’s up-and-down stroke • What happens when there is extra vertical (up‑and‑down) play in the ring groove • Location of piston lands in relation to the ring (above vs. below)

💭 Think About

• Think about how the ring will move in its groove when the piston changes direction at top dead center and bottom dead center. Where will it hit? • If there is too much side clearance, does the ring stay tight against one land, or does it have room to bang back and forth? What part of the piston takes that impact? • Compare the physical position of the land above the ring and the land below the ring. Which one is more likely to be struck when the ring ‘rocks’ or slams due to extra clearance?

✅ Before You Answer

• Sketch a simple piston, one ring groove, and label the land above and land below the groove. • Visualize the ring’s motion when the piston is on the compression/power stroke versus the exhaust/intake stroke and which land it contacts each time. • Before choosing, be sure you understand that “hammering” means repeated impact wear on one specific land surface, not general expansion or scuffing.