FAA Powerplant Written Practice Test

Where is the primary capacitor located in a high-tension magneto?

1. In series with the ignition coil

2. In parallel with the battery

3. In parallel with the breaker points

4. In front of the spark plugs

The correct answer is: In parallel with the breaker points

The primary capacitor in a high-tension magneto is located in parallel with the breaker points. This positioning is crucial for the functioning of the magneto system, as the capacitor serves to stabilize the electrical discharge during the cycle of ignition. When the breaker points open, the rapid change in current flow from the ignition coil generates a high voltage. The capacitor momentarily stores electrical energy, allowing for a smoother discharge and helping to prevent arcing at the points, which can impair their lifespan and performance. This function is essential as it ensures that the magneto can produce a strong, consistent spark at the spark plugs when needed. Proper operation of the capacitor contributes to the overall reliability and efficiency of the ignition system in an internal combustion engine. The other options do not accurately reflect the configuration of the components within a high-tension magneto.