FAA Powerplant Written Practice Test

What component is typically checked for heat crack during an engine overhaul?

1. Connecting rods

2. Exhaust valves

3. Crankshaft bearings

4. Cylinder heads

The correct answer is: Cylinder heads

During an engine overhaul, the cylinder heads are a critical component that is typically checked for heat cracks. Cylinder heads are subjected to high temperatures and pressures during engine operation, which can lead to thermal stress and the possibility of cracking. Heat cracks can significantly impair the performance of an engine by affecting the sealing surfaces and the ability to maintain compression. Inspecting the cylinder heads for such cracks involves a careful visual inspection and often non-destructive testing methods, such as dye penetrant or ultrasonic testing, to ensure the integrity of the component before reinstallation. Monitoring for these cracks is vital because they can lead to engine failure if not identified and repaired. Other components, while also important to check during an overhaul, do not commonly experience heat cracking the way cylinder heads do due to differences in their design and exposure to heat.