In a pressure-type carburetor, where is the discharge nozzle located relative to the throttle valve?

In a pressure-type carburetor, where is the discharge nozzle located relative to the throttle valve?

• A. Upstream of the throttle
• B. In the float chamber
• C. After the exhaust
• D. On the engine side of the throttle valve

Answer: (D)

In a pressure-type carburetor, fuel must be added to the air stream after the air has been metered by the throttle. The discharge nozzle is placed on the engine side of the throttle valve so fuel is injected into a controlled, metered airstream. This guarantees that fuel flow tracks the amount of air being drawn into the engine, giving a stable and proportional air-fuel mixture across different throttle openings. If the nozzle were upstream of the throttle, fuel would be exposed to unmetered air and pressure, leading to inconsistent mixture, potential flooding, or lean/rich conditions as the throttle position changes. The engine-side location ensures proper atomization and reliable metering with throttle control.

In a pressure-type carburetor, fuel must be added to the air stream after the air has been metered by the throttle. The discharge nozzle is placed on the engine side of the throttle valve so fuel is injected into a controlled, metered airstream. This guarantees that fuel flow tracks the amount of air being drawn into the engine, giving a stable and proportional air-fuel mixture across different throttle openings. If the nozzle were upstream of the throttle, fuel would be exposed to unmetered air and pressure, leading to inconsistent mixture, potential flooding, or lean/rich conditions as the throttle position changes. The engine-side location ensures proper atomization and reliable metering with throttle control.