What is the primary function of the crankcase in an engine?

The primary function of the crankcase in an engine is to contain the engine oil. The crankcase is the lower part of the engine block, and its main role is to provide a reservoir for the lubrication oil that supports the moving parts of the engine. This oil is crucial for reducing friction, dissipating heat, and cleaning the engine components.

In addition to holding the oil, the crankcase provides necessary structure and support to the engine's moving components such as the crankshaft and connecting rods. By containing the oil, it ensures proper lubrication during engine operation, which is essential for maintaining engine efficiency and longevity. This function is critical for the overall performance and reliability of a four-stroke engine.