What are modern crankshaft seals designed to prevent?

Modern crankshaft seals are designed primarily to prevent oil leakage. The crankshaft is a critical component in an engine that converts the linear motion of the pistons into rotational motion. It operates within an environment where it is constantly lubricated by engine oil. Seals are installed at both ends of the crankshaft to ensure that the oil remains contained within the engine, preventing it from leaking out. This containment is essential for maintaining proper lubrication, preventing wear and tear on engine components, and ensuring efficient engine operation. By effectively sealing the crankshaft, these seals help maintain the engine's performance and longevity, highlighting their crucial role in engine reliability.

Other possibilities, like preventing dust contamination or vibration, while important to various aspects of engine integrity, are not the primary function of crankshaft seals. Heat transfer is managed by the cooling system and not decided by the seals themselves. Therefore, the main purpose of crankshaft seals is indeed to prevent oil leakage.