PP206 Recip Ignition
What happens when the magnet is in e-gap position? (choose all that apply)
-magnetic field collapses -breaker points open -spark fires
What speed does the distributor spin?
1/2 crankshaft
Which CFR covers ignition system requirements?
14 CFR 33
How many transformers are required for a 4 cylinder engine with a low tension magneto?
8
What test instrument could be used to test an ignition harness for suspected leakage?
A high tension lead tester
What is the difference between a low-tension and a high-tension engine ignition system?
A low-tension system uses a transformer coil near the spark plugs to boost voltage, while the high-tension system voltage is constant from the magneto to the spark plugs.
A magneto is a permanent magnet _____ generator.
AC
What will be the results of increasing the gap of the breaker points in a magneto?
Advance the spark and decrease its intensity .
What will be the results of increasing the gap of the breaker points in a magneto?
Advance the spark and decrease its intensity.
When using a timing light to time a magneto to an aircraft engine, the magneto switch should be placed in the
BOTH position
The induction vibrator supplies pulsing ______ current to the __________ winding of the coil pack.
DC; primary
A magneto converts 12 DC to pulsing AC current.
False
Current flows from the primary coil to the secondary coil through the common ground to create the spike in voltage needed to light off a spark plug.
False
Once the engine reaches its coming in speed and the magneto is self sustaining, the pilot disengages the impulse coupling.
False
Retard breaker points generate and delay the spark.
False
The impulse coupling body/housing rotates with the engine only during starting then disengages after the engine reaches its coming-in speed.
False
The primary windings consist of roughly 200 turns of fine copper wire.
False
You might need to rotate the magneto slightly when installing it on the engine to set the internal timing.
False
What likely effect would a cracked distributor rotor have on a magneto?
Ground the secondary circuit through the crack.
Which is not a type of ignition system?
Hamster Wheel
Which of the following could cause damage to the nose ceramic or to the electrode of an aircraft spark plug?
Improper gapping procedure
Magneto breaker points must be timed to open when the
Rotating magnet is positioned a few degrees before neutral.
When a spark is retarded during engine start, it usually will not fire till which position?
TDC
What is the purpose of using an impulse coupling with a magneto?
To produce a momentary high rotational speed of the magneto.
Why are high-tension ignition cables frequently routed from the distributors to the spark plugs in flexible metallic conduits?
To reduce the effect of the high-frequency electromagnetic waves emanated during operation.
A shower of sparks system is a modern version of the induction vibrator and uses a set of retard breakers located in the left magneto.
True
The capacitor helps accelerate the collapse of the magnetic field.
True
The faster the magnetic field collapses, the higher the voltage is produced in the secondary coil.
True
Capacitance afterfiring in most modern spark plugs is reduced by the use of
a built-in resistor in each plug
Failure of an engine to cease firing after turning the magneto switch off is an indication of
an open P-lead to ground.
Which set of breaker points need to be open in order for a spark to be fired when the shower of sparks system is activated.
both sets of breakers
Worn ______ will cause advanced timing.
breaker points
A defective primary capacitor in a magneto is indicated by
burned and pitted breaker points.
In a battery ignition system, what opens the breaker points?
cam
Which component transfers the voltage from the coil pack tab to the distributor?
carbon brush
The pole shoes complete the magnetic circuit by connecting the ____________ to the rotating magnet.
coil core
The distributor receives voltage from what component in a battery ignition system?
coil output tab
The speed in which a magneto must rotate in order to produce enough voltage to fire a spark plug is called what?
coming in speed
A purpose of the ignition system is to create and deliver a high voltage spark to each _____________ in all operating conditions at the correct moment in the operating cycle.
cylinder
What is the condition called in which a spark jumps to the wrong electrode in the distributor block?
flashover
The greatest density of flux flows through the coil when the magnet is at what position?
full register
In a high-tension ignition system, the current in the magneto secondary winding is
induced when the primary circuit is interrupted
What is the term called when the engine attempts to turn in the opposite direction of travel?
kick back
Which is not a common type of ignition booster?
magneto vibrator
Which circuit is the hardened steel shaft part of?
mechanical
In reference to a "Shower of Sparks" ignition system, (1) the retard breaker points are designed to keep the affected ignition system operating if the advance breaker points should fail during normal engine operation (after start). (2) the timed opening of the retard breaker points is designed to prevent engine "kickback" during start. Regarding the above statements,
only No. 2 is true
How is the condenser installed in the primary circuit?
parallel to the breaker points
A magneto ignition switch is connected
parallel to the breaker points.
The breaker points are part of which system?
primary circuit
The breaker points in a battery ignition system are connected in __________ with the primary winding?
series
When both spark plugs in a cylinder fire at the same time, the magnetos are _________ .
synchronized
In a high-tension ignition system, a primary capacitor of too low a capacity will cause
the breaker contacts to burn.
When internally timing a magneto, the breaker points begin to open when
the magnet poles are a few degrees beyond the neutral position.
A magneto is hot when the primary circuit is
ungrounded
Magneto timing drift is caused by erosion of the breaker points and
wear of the cam followers
What did you use to determine if the #1 cylinder was on the compression stroke?
your thumb
