Reciprocating Engine Ignition Systems Flashcards
7 cards from real AMT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Reciprocating Engine Ignition Systems flashcards as text
What is the recommended method for cleaning lead-fouled spark plugs on an aircraft engine?
Answer: Use an abrasive-type spark plug cleaner with compressed air blast
An abrasive-blast (vibratory) cleaner and air blast is the FAA-accepted method for removing lead deposits from aircraft spark plugs before regapping and testing.
Why are aircraft spark plugs rotated between top and bottom positions during scheduled maintenance?
Answer: To equalize wear since lower plugs tend to run hotter due to oil splash
Lower spark plugs run hotter because heat and combustion residues pool at the bottom of inverted or horizontally-opposed cylinders, so rotation extends overall plug service life.
A magneto that produces no output but has good breaker points and condenser most likely has:
Answer: An open or shorted secondary coil winding
The secondary coil produces the high-voltage output; if it is open or shorted, no spark voltage reaches the distributor regardless of primary circuit condition.
When installing a new spark plug, the torque specification is critical because:
Answer: Over-torquing can crack the ceramic insulator; under-torquing allows combustion gas leakage
Excessive torque cracks the fragile ceramic insulator, while insufficient torque allows hot combustion gases to blow by the seat, risking cylinder head damage.
What is the function of the retard breaker points found in some aircraft magnetos?
Answer: Provide a retarded spark for starting to prevent kickback
Retard breaker points fire the spark slightly after TDC during engine cranking, preventing the engine from kicking back against the starter or hand-propping motion.
Which FAA document provides acceptable means of compliance for spark plug inspection intervals on certificated aircraft engines?
Answer: AC 43.13-1B, Acceptable Methods, Techniques, and Practices
AC 43.13-1B provides FAA-accepted maintenance practices including spark plug inspection, cleaning, and replacement intervals for certificated aircraft engines.
What condition is indicated when a spark plug shows a white, chalky deposit on the insulator and electrode?
Answer: Overheating or detonation, possibly from too-lean mixture or pre-ignition
White or chalky deposits indicate very high temperatures caused by an over-lean mixture, pre-ignition, or detonation, which can quickly destroy piston and valve components.