AGK

Question 1

Talk about the engine

Question 2

Do we have an injection system ?

Answer 2

No, we only have 2 carburetor’s

Question 3

Fuel System

Question 4

Electrical System

Question 5

Explain the Ignition System

Question 6

Brake System

Question 7

What is a carburetor and how does it works?

Answer 7

A carburetor is a device in an engine that mixes air and fuel in the correct ratio before it enters the engine for combustion. It helps the engine run smoothly by ensuring the proper fuel-air mixture for different operating conditions.
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1. Airflow into the Carburetor:
Air enters through the carburetor as the engine pulls it in.

2. Fuel Mixing:
   - Inside the carburetor, there’s a venturi (a narrow passage) where the airflow speeds up and pressure drops.
   - This low pressure sucks fuel from the fuel bowl into the airstream through small nozzles (jets).
3. Air-Fuel Ratio:
   The carburetor adjusts the amount of air and fuel to create the correct mixture (about 15 parts air to 1 part fuel for most engines).
4. Throttle Control:
   The throttle controls how much air and fuel enter the engine, adjusting power.
   Open throttle = more fuel and air = more power.
   Closed throttle = less fuel and air = idle.

Question 8

What is carburetor icing and how to recover from it ?

Answer 8

Carburetor icing happens when moisture in the air freezes inside the carburetor, blocking airflow and reducing engine power. It occurs in cool, humid conditions, even above freezing temperatures.

Is caused by the temperature drop in the carburetor, as an effect of fuel vaporization, and the temperature drop associated with the pressure drop in the venturi

How Carburetor Icing Happens:
1. Airflow and Fuel Mix:
* In the carburetor, air mixes with fuel, creating a fine mist.
2. Cooling Effect:
* The pressure drop and evaporation of fuel cause the air to cool rapidly, sometimes by up to 20–30°C.
3. Moisture Freezes:
* If the air contains moisture, it can freeze in the carburetor, forming ice around the throttle valve and restricting airflow.
* This causes engine power to drop.

Symptoms:
- Drop in RPM (fixed-pitch propeller).
- Reduced manifold pressure (constant-speed propeller).
- Engine roughness.

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How Carb Heat Fixes It:
1. Redirects Hot Air:
* The carb heat system draws warm air from around the engine exhaust (unfiltered) and directs it into the carburetor.

2. Melts the Ice:
   
   • The warm air melts the ice buildup, restoring normal airflow and power.
3. Prevents Further Icing:
   
   • Keeps the carburetor warm enough to stop new ice from forming as long as carb heat is on.

Question 9

How does the Choke works?

Answer 9

1. Normal Air-Fuel Mixture:
   In regular operation, the engine mixes air and fuel in a balanced ratio (lean enough for efficient combustion).
2. What the Choke Does:
   When the engine is cold, the fuel doesn’t vaporize well, so the engine struggles to start. The choke reduces the amount of air entering the engine, making the fuel-air mixture richer (more fuel compared to air).
3. How It Works Mechanically:
   The choke is either a valve or flap in the carburetor that partially blocks airflow.
   When you pull the choke lever, the valve closes slightly, restricting air and increasing fuel delivery.
4. Effect:
   The richer mixture ignites more easily in the cold engine, helping it start.
5. After Starting:
   Once the engine warms up, you push the choke lever back in, restoring the normal air-fuel mix for efficient operation.