Fuel seeping from GAV

I should clarify that I’m not using the fuel level in the bowl as a gauge of where the fuel level is while assembled. This was after being run out of fuel with the valve closed yesterday. There was so little fuel in the bowl that I doubt the float was even closed and it was still coming out the jets. Obviously I need to replace the tank valve but that has to wait until the tank is empty. Neither the new or old float valves leaked a drop when I took the bowl off and held them barely closed with a loosely tied string. This is why I’m confused by this. It’s almost like there’s some sort of siphon thing happening while the float is hanging open. I’ll have to see if anything changes with this float valve.
 
So update time. I swapped the repro float valve back to the old one and the car sat for some time to recheck the leaking. Still seeping and leaving a small spot on the floor and filling the garage with fumes. It’s not the float or fuel level. When I started it this morning, there was only about 5 seconds worth of fuel in the bowl and it was still leaking. Looking closely at it, it appears that there’s a decent size pore in the casting right next to the venturi and it’s right above the GAV. I’m starting to think this is the source of the fuel and it’s just running down to the valve. So I think this is one of the rare situations where fuel is wicking up through pores or hairline cracks in the casting. Took the car on a 50 mile drive today and ran great but she’s just leaky. I guess I’ll need to find another carb lower half to swap the jets in to and try that.
 
I notice that the hole for the secondary well is too close to the main bolt hole. I have seen cracks between both holes. Fuel then leaks out the main bolt. A static test of the bottom casting should indicate a fuel leak.
 
I had noticed that small piece of the casting that was missing next to the secondary well. Wouldn’t surprise me if there’s a crack radiating from that area. My other theory is that nine decades worth of obscenities have permeated the castings and has left this carburetor bitter and unwilling to cooperate.
 
I'll bet there's porosity or a small crack in the casting.When people over tighten that carburetor bolt that can put a tremendous amount of pressure on the old cast iron. It's quite possible to have cracked over the almost 100 year old casting in my opinion!!!
They made over 5 million of these carburetor castings, to think none of them had quality control issues like porosity is just not a reasonable thought in my opinion!!!
My background is in quality control, and I’ve dealt with many castings over the years and even with today’s modern technology, there can be an awful lot of porosity, even in today’s castings.
 
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