FAA Powerplant questions with correct answers

What are the different types of piston rings? CORRECT ANSWER Compression rings, oil control rings, and scraper rings. What type of piston rods are commonly found in radial engines? CORRECT ANSWER Master and articulating What types of bearings are generally found in reciprocating engines? CORRECT ANSWER Plain, roller, and ball bearings What is the indication of valve blow-by? CORRECT ANSWER A hissing or whistle when pulling the propeller prior to starting the engine. What is the purpose of using more than one spring for valve closing? CORRECT ANSWER Eliminate valve surge What is the purpose of valve overlap? CORRECT ANSWER better volumetric efficiency and lowers the cylinder operating temperatures Describe the inspection you would give the valve springs during engine overhaul? CORRECT ANSWER Clean, inspect for cracks, breaks, overheating and then for compression strength. What is the purpose of using valves with sodium filled stems? CORRECT ANSWER They dissipate heat fast