ORIGINAL: samolot
I said i had a slit, but i hcanged the fuel line. No leaks in the fuel line. Actually there is no air coming out of the tank. Its pretty much perfect. It just quits during verticle flight.
Have you checked that your fuel pickup in the tank isn't too close to the rear of the tank? Going vertical can sometimes stretch the fuel line enough that the orifice in the clunk is up against the rear tank wall. It is best to leave a 1/4" or more of space between the rear of the clunk and the rear tank wall.
Good luck solving the problem. Please let us know what it was that was causing the flame outs. TIA
Ed Cregger