FAA Powerplant Written Practice Test

What condition can cause excessive cylinder wear in an engine?

1. Incorrect ignition timing

2. Poor lubrication

3. High fuel quality

4. Using synthetic oil

The correct answer is: Poor lubrication

Poor lubrication is a primary factor that can lead to excessive cylinder wear in an engine. Lubrication is crucial for reducing friction between the moving parts within the engine, particularly within the cylinders where the pistons move. When lubrication is inadequate, the surfaces of the piston rings and cylinder walls can experience increased contact, leading to accelerated wear. This can result from several issues, including using the wrong type of oil, low oil levels, or oil that has degraded due to age or contamination. In terms of the other options, while incorrect ignition timing could lead to other issues that may indirectly affect the cylinder wear over time, it is not a direct cause. High fuel quality generally promotes better combustion and lower engine wear, and using synthetic oil is often beneficial as it provides better lubrication and doesn't cause excessive wear, in fact, synthetic oils can enhance engine performance and longevity.