FAA Powerplant Written Practice Test

In which location is the main oil filler typically found on a reciprocating engine?

1. At the oil cooler

2. Just after exiting the oil pressure pump

3. Before the oil filter

4. Near the crankshaft

The correct answer is: Just after exiting the oil pressure pump

The main oil filler on a reciprocating engine is typically located just after exiting the oil pressure pump. This position allows for easy access to fill the oil system directly where the oil is pressurized and circulated throughout the engine. It's important to ensure that oil is filled where it can flow effectively through the system, enabling proper lubrication of engine components. Filling oil directly at this point helps to reduce the chance of air being introduced into the oil system and ensures that the oil quickly reaches the areas that need lubrication, especially when starting the engine or after a change. Having the oil filler at this location also aids in maintenance practices, making it convenient for technicians to check and maintain oil levels without having to navigate through various engine parts.