FAA Powerplant Written Practice Test

Besides lubricating, what other functions does engine oil perform?

1. Regulates fuel pressure

2. Cools, seals, cleans, prevents corrosion, cushions impact

3. Monitors engine temperature

4. Filters the fuel system

The correct answer is: Cools, seals, cleans, prevents corrosion, cushions impact

Engine oil serves several critical functions beyond just lubrication, which play a vital role in the overall performance and longevity of an engine. One of the primary functions of engine oil is to cool the engine by dissipating heat away from moving parts. This cooling effect is essential, as it helps maintain optimal operating temperatures, preventing overheating and potential damage. Additionally, engine oil acts as a sealant, creating a barrier between the piston rings and cylinder walls. This sealing helps maintain compression within the combustion chamber, which is crucial for efficient engine operation. Furthermore, engine oil has cleaning properties; it suspends contaminants and particles that can accumulate within the engine, preventing them from causing wear and tear on the internal components. Regular oil changes ensure that these particles do not build up and affect engine performance. Finally, engine oil provides protection against corrosion by forming a protective film on metal surfaces, which helps to shield them from moisture and harmful chemical reactions. It also cushions impacts, absorbing shocks that occur during the engine's operation, thereby protecting various components from premature wear. These functions collectively enhance the engine's efficiency, reliability, and longevity, which is why the choice highlighting these attributes captures the comprehensive role of engine oil effectively.