AMP - Aviation Maintenance Technician Powerplant Practice Exam

The primary function of a pre-oiler in engine operation is to supply oil to engine components before startup. This process is crucial because it ensures that all moving parts receive lubrication before the engine is cranked, which minimizes wear and damage that can occur due to metal-to-metal contact when the engine first starts running. Proper lubrication is essential for the longevity and efficient operation of an engine, as it reduces friction, helps dissipate heat, and ensures that components move smoothly.

By having oil circulating through critical areas such as bearings, camshafts, and oil galleries before the engine is activated, the pre-oiler effectively protects these components immediately upon startup. This is particularly important in situations where the engine has been sitting idle for an extended period or in cold start conditions, where oil may have settled away from vital areas.

Options that suggest other functions, such as cooling the engine components, removing contaminants, or increasing fuel pressure, do not accurately define the role of a pre-oiler and highlight different aspects of engine maintenance and operation. Thus, focusing on the pre-oiler's role in lubrication before startup accurately captures its primary purpose.