Crankshaft runout checks are usually performed under which conditions?

Crankshaft runout checks are usually performed under which conditions?

• A. During engine overhaul and after a prop strike
• B. During annual inspection
• C. After a prop strike or sudden engine stoppage
• D. During 100-hour inspection

Answer: (A)

Crankshaft runout checks measure how far the crankshaft deviates from true rotation, which reveals any bending or misalignment that could affect engine operation. This measurement requires access to the crankshaft and precise setup with dial indicators, so it’s done when the engine is opened up during overhaul to verify overall condition and determine if the crank is within tolerance. A prop strike is a common cause of crankshaft damage because the sudden impact can bend or twist the shaft, making a runout check essential before reuse. Routine annual or 100-hour inspections don’t typically involve disassembly for this precise measurement, and a sudden engine stoppage is an abnormal event that may lead to damage but isn’t a standard trigger for runout checks unless damage is suspected.

Crankshaft runout checks measure how far the crankshaft deviates from true rotation, which reveals any bending or misalignment that could affect engine operation. This measurement requires access to the crankshaft and precise setup with dial indicators, so it’s done when the engine is opened up during overhaul to verify overall condition and determine if the crank is within tolerance. A prop strike is a common cause of crankshaft damage because the sudden impact can bend or twist the shaft, making a runout check essential before reuse. Routine annual or 100-hour inspections don’t typically involve disassembly for this precise measurement, and a sudden engine stoppage is an abnormal event that may lead to damage but isn’t a standard trigger for runout checks unless damage is suspected.