Instruction manual

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The purpose of the Carburetor is to supply a combustible mixture of fuel and air

to the Pulse Jet Engines. The carburetor uses four systems to create this

mixture. These systems are:

1. A Venturi

2. A Metering Chamber

3. A Fuel Pump

4. A Fuel Needle

The Venturi is the air passage through the Carburetor. When air moves through a

Venturi a partial vacuum is created. The strength of the vacuum varies

proportionately to the amount of air flowing through the Venturi. When a

constant volume of gasoline is connected to the Venturi, the vacuum created by

the Venturi will draw an amount of gasoline proportional to the air flow past the

Venturi and disperse the gasoline in the airflow. This arrangement allows the

carburetor to always supply the correct ration of fuel and air to the engine.

The Metering Chamber maintains a constant volume of gasoline for the Venturi

and prevents gasoline from leaking out through the Carburetor should the

machine be overturned. As gasoline enters and begins to fill the Metering

Chamber it presses out on the Metering Diaphragm allowing the spring under the

Metering Lever to push out on the lever closing the Inlet Needle Valve. When the

air flowing through the Venturi draws gasoline from the Metering Chamber, the

Metering Diaphragm moves in pressing in the Metering Lever and opening the

Inlet Needle Valve, thereby allowing the metering Chamber to fill with gasoline

again. When the engine is not running, vacuum is not created in the Venturi to

move the Metering Diaphragm so the Metering Diaphragm does not move in and

out. In this condition the spring behind the Metering Lever holds the Inlet Needle

Valve closed preventing gasoline from leaking through the Carburetor if the

machine is overturned.