carbs overflowing possible floats sticking after rebuild

[VegasF6]

Fuel rails were leaking, I was in a hurry and hired someone to do the job.
He screwed me over every way imaginable and they started leaking again within days, finally I was forced to do the job myself.

Got carbs on bench, separated and put in the cheaper oring kit from redeye. Did not do the whole carb kit as I just paid this other guy to do it (and hopefully he did) anyhow I did pull the float bowls to look inside, they were mostly clean I would say. Put the bowls back on and made up some drain lines (as the "mechanic" just threw the drain assembly away) and put on the carbs, like 3 or 4 of them just filled up with fuel and overflowed everywhere, air even coming out of the air tubes. Like stuck floats.

Pulled carbs, put on bench, turned them upside down once or twice and filled them with fuel and they don't overflow.

Thoughts? Anyway I could have installed something incorrectly and caused the floats to remain open??

[Pete]

What happened is not that unusual.

Often a small piece of crud will get in the needle valves and get flushed out and seal.

Set the carbs on the bench and fill them with gas to check for leaks.

If they seal up fine flush some clean gas thru them and test again.

Often after a carb has sat without gas they will not seal immediately and needs to soak or be flushed and soaked before they will work correctly.