IDA3C Weber Troubleshooting Options

[Cfletch]

Hey there everyone, working on getting my 6 conversion going here and I was able to hook up a temp fuel system in place of my tank while I am waiting on a few parts. I wanted to get the car to idle with its new fuel pump (not yet regulated down to 3.5psi) rated at 5 PSI max. I wanted to get the carb bodies full of fuel and get some pressure into the system and as soon as the pump turned on with the ignition the carbs essentially started dumping fuel down my intakes. Almost as if there was an internal leak causing fuel to just enter their respective cylinders. I'm new to down draft webers so this confuses me. I popped the top off of one of the carbs and noticed the fuel level was extremely low in the bowls so it was not like the needle and seat were stuck or a float was stuck causing it to overfill. Kind of stumped here as these carbs are rebuilt. Really any suggestions are good here. the float level was set, the needle and seats are good and not sticking at all.

I read somewhere but not in much detail that the bowls are vented? I have these little plunger-esq things in each vent tube that I have not yet pulled out. Would that be the source of my problem? If the bowls couldn't vent its just pressurizing the changes and causing the fuel to just leak down into the engine?

[Cfletch]

What would be an official test on the needle/seat? I pulled them both out of the carb body, lips to top and blew hard on them, used finger to press ball and that was my check. They were free, didn't get stuck at all and when closed, I was unable to blow through. I did an initial set of the floats on the bench. I have read that the final adjustment with shims and what not would be on a running motor, do not want to start the engine because with ignition on its just dumping fuel down the throats. Again if the floats/needle and seat were suspect, I would assume that my fuel bowls would first fill up in order for the bodies to start leaking fuel out of wherever it could escape, that is not happening in my case as the bowls are maybe 1/5 or 1/4 full.

I would suspect even the same result when/if my fuel pressure is too high, it would 'bypass' the needle seat valve because too much pressure and then fill up my bowls, then lead to a leaking situation. I'm stumped because my bowls are no where near full.