BAKERS ORAL POWERPLANT QUESTIONS & ANSWERS

How are reciprocating engines classified? - correct answer 1) Cylinder Arrangement w/ respect to crankshaft (in-line, V-type, radial and opposed) 2) Method of cooling (liquid cooled, or air cooled) what are the different types of piston rings - correct answer compression rings, oil control rings and scraper rings what are the main causes of a cylinder having low compression - correct answer broken piston rings, rings that are not seated properly, burnt valves and poorly seating valves what is the purpose of the oil control rings? - correct answer they are used to control the thickness of the oil film on the cylinder walls what may be the result of installing piston rings incorrectly - correct answer excessive oil consumption what type of piston rods are commonly found in radial engines - correct answer a master and articulating rod assembly what type of bearings are in general use in reciprocating engines - correct answer plain, roller and ball bearings what is the indication of valve blowby - correct answer a hissing or whistle when pulling the propeller through by hand what is the purpose of using more than one spring for valve closing - correct answer valve springs will resonate (or surge) at certain engine speeds. 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 they should be cleaned thoroughly, then visually inspected for evidence of overheating, cracks, broken ends, and compression strengh what is the purpose of usi