I had a similar problem yesterday.. I run a Header tank setupin me Ultra Stick Lite1.2 as I was fueling (manual pump the uys waiting to watch me fly were beting on how many revolutions it would take to fill the tanks.. After 67 I knew somthing was wrong.. I looked under the plane and noticed fuel dripping near the LG.. After pulling the wwing and ripping out the bar holding in the tanks I found the 12 oz. main tank was full (thank god) and only 2 oz. (header) had leaked out. So after drying that out and putting on new lines and Stuffing the tanks back into the plane (Harder than it seems) I've now been at the fiel 1hour 30 minutes and havent started the engine.. Get everything back together and have to charge RX batts. So finally when everythings finished I taxi out and take off,. Turned out to be my best day flying yet.. Did my first rolling circles!