Mine has the same issue. I suspect part of the problem is that fuel is evaporating out of the vent, but more than likely it is getting siphoned out of the float bowl but into the fuel line. I posted this question awhile back. https://www.hotrodders.com/forum/pot-...et-234542.html
hi - tx for the post on the intake matters. I see u have a qjet avatar.. I redid mine about 18mnth ago, i had the non leaking aluminium plugs, but epoxied them anyway. I notice the car wnt start after sitting 2-3 days, as if the fuel has drained somewhere, could this be warping / gasket something else?