Which component is not typically found in the engine block?

• A. Heater Core
• B. Main bearings
• C. Cylinder walls
• D. Oil galleries

Answer: (A)

The thing being tested is where components belong in relation to the engine block versus other systems. The engine block houses the moving and lubricating internals: the crankshaft is supported by main bearings, the cylinder bores are defined by cylinder walls, and oil galleries run inside the block to deliver lubrication to moving parts. The heater core, while it uses engine coolant, is not part of the engine block at all—it’s a heat exchanger located in the vehicle’s HVAC system, usually in the dash, with coolant lines Feeding it from the engine. So the component not typically found in the engine block is the heater core.