What did you seal the tank with? Some sealers have problems with ethanol. That may be an old problem.
My GMC 270 was doing that, it turned out to be a vacuum leak and crud keeping the float needle open. The carb was wet with gas- leaking out the throttle plate shaft opening.
Dave
Well, my time went so quickly,
I went lickety-splitly
Out to my ol' 55.
As I pulled away slowly,
Feelin' so holy,
God knows, I was feelin' alive..... Tom Waits, Ol' 55
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