Just started phase 1 and noticed a drip from the QB Wing left tank vent line whenever the tank's more than half full, ie. when the fuel level is up to the inboard rib vent connection. Checking the forum, looks like the only cause could be a bad vent line connection inside the tank at the inboard tank rib...grrrrrr....
Nobody at Van's to talk to during Oshkosh so nothing left to do but pull the tank, buy $63 worth of hole saw and mandrel at Home Club and open it up.
The nut was fairly tight, but the flare was very large and thin. The nut would not go over the flare without turning it like a screw. so that may have jammed things up somewhat, Also the close-up shows what looks like a crack in the flare..
I guess this is the one fitting in the tank which can't be leak checked easily
Not sure what a good fix would be, there's not much room to cut or flare in such close quarters, but maybe if I removed the fitting from the rib, there would be enough room to pull the entire vent tube out and replace it with a new one.
When Van's support gets back I'll see what they recommend. Since it's a quick-build, maybe they'll just give me a new tank :-)