Your photo shows the accelerator pump well, so yes, there has to be an exit on the bottom of it. The accelerator pump rubber cup moves downward and compresses the fuel in the well, which then exits the carburetor via the pump squirters into the venturis.

As far as losing fuel from the bowls over a period of time, please read this article....
Techin' In With Fletch - June 2014

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