BAKERS ORAL POWERPLANT
CERTIFICATION EVALUATION FULL
QUESTIONS AND CORRECT ANSWERS
GRADED A+
●● what are the different types of piston rings?
Answer: Compression control and scraper
●● what are the main causes of a cylinder having low compression?
Answer: worn piston rings and poorly seated valves
●● what is the purpose of the oil control rings?
Answer: control the thickness of the oil film on the cylinder wall
●● what may be the result of installing piston rings incorrectly?
Answer: Excessive oil consumption.
●● what type of piston rods are commonly found in radial engines?
Answer: A master and articulating rod assembly.
●● what type of bearings are in general use in recip engines?
,Answer: roller ball plain
●● what is the indication of valve blowby?
Answer: hissing or whistle when pulling the propeller through by hand
●● what is the purpose of using more than one spring for valve closing?
Answer: to reduce valve surging and floating
●● what is the purpose of valve overlap
Answer: It allows better volumetric efficiency and lowers cylinder
operating temperatures
●● describe the inspection you would give the valve springs during
engine overhaul
Answer: visually inspect for overheating, cracks and compression
strength
●● what is the purpose of using valves with sodium filled stems?
Answer: sodium is an excellent heat conductor
●● what causes engine sudden stoppage?
Answer: Striking an object or engine seizure due to internal damage.
,●● What type inspection must be made after sudden stoppage of an
engine?
Answer: Complete engine tear down and inspection.
●● what is the purpose of the crankshaft dynamic dampers used in
aircraft engines?
Answer: reduce torsional vibration
●● how would you make a run out check in a crankshaft that is still
installed in the engine?
Answer: remove the propeller and attach a dial indicator. adjust the
position check for misalignment by rotating
●● What is detonation?
Answer: When last portion of the charge detonates
●● what cylinder is engine to magneto timing based on?
Answer: The number one cylinder.
●● what is engine sudden speed reduction?
Answer: when the propeller strikes an object
, ●● what can be learned about the condition of an engine by studying the
results of a compression check?
Answer: if the rings, valves and piston are sealing
●● how can a cold cylinder be located on a double row radial engine?
Answer: use a magic wand infrared laser thermometer
●● what instrument can be used to check bore for out of roundness?
Answer: Dial indicator, telescopic gauge, outside or inside micrometer.
●● what would a cold cylinder indicate
Answer: no combustion
●● where is a crack most likely to occur on a piston
Answer: where the piston pin connects (thinnest point)
●● what should be done to a nose wheel airplane before removing the
engine
Answer: support the tail of the airplane
●● what are the major components of a typical gas turbine engine?
Answer: Air inlet, compression section, a combustion section, turbine
section, exhaust
CERTIFICATION EVALUATION FULL
QUESTIONS AND CORRECT ANSWERS
GRADED A+
●● what are the different types of piston rings?
Answer: Compression control and scraper
●● what are the main causes of a cylinder having low compression?
Answer: worn piston rings and poorly seated valves
●● what is the purpose of the oil control rings?
Answer: control the thickness of the oil film on the cylinder wall
●● what may be the result of installing piston rings incorrectly?
Answer: Excessive oil consumption.
●● what type of piston rods are commonly found in radial engines?
Answer: A master and articulating rod assembly.
●● what type of bearings are in general use in recip engines?
,Answer: roller ball plain
●● what is the indication of valve blowby?
Answer: hissing or whistle when pulling the propeller through by hand
●● what is the purpose of using more than one spring for valve closing?
Answer: to reduce valve surging and floating
●● what is the purpose of valve overlap
Answer: It allows better volumetric efficiency and lowers cylinder
operating temperatures
●● describe the inspection you would give the valve springs during
engine overhaul
Answer: visually inspect for overheating, cracks and compression
strength
●● what is the purpose of using valves with sodium filled stems?
Answer: sodium is an excellent heat conductor
●● what causes engine sudden stoppage?
Answer: Striking an object or engine seizure due to internal damage.
,●● What type inspection must be made after sudden stoppage of an
engine?
Answer: Complete engine tear down and inspection.
●● what is the purpose of the crankshaft dynamic dampers used in
aircraft engines?
Answer: reduce torsional vibration
●● how would you make a run out check in a crankshaft that is still
installed in the engine?
Answer: remove the propeller and attach a dial indicator. adjust the
position check for misalignment by rotating
●● What is detonation?
Answer: When last portion of the charge detonates
●● what cylinder is engine to magneto timing based on?
Answer: The number one cylinder.
●● what is engine sudden speed reduction?
Answer: when the propeller strikes an object
, ●● what can be learned about the condition of an engine by studying the
results of a compression check?
Answer: if the rings, valves and piston are sealing
●● how can a cold cylinder be located on a double row radial engine?
Answer: use a magic wand infrared laser thermometer
●● what instrument can be used to check bore for out of roundness?
Answer: Dial indicator, telescopic gauge, outside or inside micrometer.
●● what would a cold cylinder indicate
Answer: no combustion
●● where is a crack most likely to occur on a piston
Answer: where the piston pin connects (thinnest point)
●● what should be done to a nose wheel airplane before removing the
engine
Answer: support the tail of the airplane
●● what are the major components of a typical gas turbine engine?
Answer: Air inlet, compression section, a combustion section, turbine
section, exhaust
