🔍 Key Concepts

• Role of main bearings in supporting rotating shafts • Difference between main bearings and connecting rod bearings in a diesel engine • Where the crankshaft is supported inside the engine

💭 Think About

• Which engine part must be supported so it can rotate smoothly inside the engine block? • Which bearings directly support the crankshaft journals versus those that connect the crankshaft to the connecting rods? • Think about which components move relative to each other at the main support points of the crankshaft.

✅ Before You Answer

• Identify which bearings support the crankshaft within the block rather than between two moving links • Separate in your mind: bearings for piston/rod connection, bearings for rod/crank connection, and bearings for crank/block support • Confirm which option best describes the stationary structure of the engine that carries the crankshaft’s load (engine block vs. moving parts**)