USMarine15

Ive got a 2003 vstar classic. When i start the bike in starts spilling alot of fuel out of the vent tube behind the air intake. The bike shop down the road told me i need my carbs rebuilt. I tried tapping on them with a screwdriver and added 1/3 a can of seafoam to the tank of gas but no luck so far. Anyone else have this problem or any other ideas?