FAA Powerplant Written Practice Test

What can result from improper alignment of exhaust system components?

1. Increased fuel consumption

2. Gray streaks on the exhaust system

3. Higher operational temperatures

4. Reduced engine power

The correct answer is: Gray streaks on the exhaust system

Improper alignment of exhaust system components can lead to gray streaks on the exhaust system, which is a visible indicator of issues. When the exhaust system is not properly aligned, it can create points of friction or contact between the exhaust components, which may cause wear and heating of the surfaces involved. This increased wear can lead to a condition known as "hot spotting," where specific areas of the exhaust system become overheated due to restricted exhaust flow or improper fit, resulting in discoloration such as gray streaks. This discoloration is a warning sign that may indicate potential long-term damage to the exhaust system. It’s important to address this misalignment to ensure optimal exhaust flow, prevent additional wear, and maintain the overall efficiency and longevity of the system.