Carb magic - pickup tube self siphons

Oh and sorry in advance but this is a bit OT since it's for a lawnboy. Problem: Gas comes oozing out of the top of the pickup tube into the throttle when the gas is turned on.

1st, I replaced the float valve & seat and gas still came oozing out, but I could turn the carb upside down and gravity on the float made the valve seal air tight. Even though the float sure seemed fine I replaced it thinking that could be the only other problem. Gas still came out.
Trying all kinds of things, I found that if I take the pickup tube and needle out completely and leave everything else the same ... no problems ... works like it's supposed to. Leave the needle out and replace only the pickup tube? Gas comes oozing right back out again.

Any ideas?

Oh and yes I realize that without the pickup tube, the gas level has to come a bit higher, but only by about 1/8 inch. The tube that the pickup tube screws into extends well below the float level.

Thanks.

Jake

When I had the tank on it's side, I remember gas squirting out of the vent in the cap, so I know it's not totally blocked. But that's something else to try ... just leaving the cap off and see if it changes something.

But, you mentioned the primer. I've been assuming that it's just another symptom, but it doesn't seem to push the gas out as hard. I can't find a leak though (push down on primer, put finger over hose end, release primer, works fine).

I think after using my head a little bit more now that I've thrown a few parts at it, I've ruled out that the new float is bad.

When I had the pickup tube out and everything hooked back up, I turned off the fuel and disconnected the fuel line to the carb. I hooked up a vinyl tube and tried to blow into the carb past the valve. I couldn't get a bubble through, so it seems like it did it's job.