(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) Blow-back is when the air flow through a carburetor suddenly changes direction. This is often caused by incorrect ignition.
⇒ The tank design allows full fuel flow from the gas pump directly into the tank without
blow-back. ⇒ As the throttle is opened, there is heavy blow-back of fuel from the carburetor air intake. ⇒ The interruption of flow through the carburetor causes a rebound of the air with consequent
blow-back of fuel from the carburetor entrance.
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