I finally finished my fuel tanks and leak tested them this past weekend. No leaks!!!!!!!! However I discovered that the AN913-3D plug, that's the blue aluminum plug that goes in the top opening on the inside rib of the fuel tank(s) intended for a fuel return line if your powerplant uses one, is hopelessly stuck. I've tried hard enough to back it out that I have rounded the corners. Obviously there was some gorilla snot contaminating the threads. My choices are to either simply put a glob of snot over the plug and call it good, or to try again to remove the plug so I can use some proper thread sealant making this fitting usable for a future fuel return line should one ever be needed.
My fear is causing damage; either shearing the rivets of the flange into which it is screwed (and stuck), buckling the rib, or causing separation between the rib and the skin. I surely don't want to make things worse, but at the same time it drives me crazy that after all the effort and care that went into building the tanks that now I have a stuck plug. Any thoughts on how to remove it? I've tried WD-40 hoping it would seep into the threads, but no joy. I have a bottle of CRC Freeze Off on order hoping I might be able to shrink it just enough with cold temps to break the bond. I'd appreciate thoughts from others who have run into something similar.
My fear is causing damage; either shearing the rivets of the flange into which it is screwed (and stuck), buckling the rib, or causing separation between the rib and the skin. I surely don't want to make things worse, but at the same time it drives me crazy that after all the effort and care that went into building the tanks that now I have a stuck plug. Any thoughts on how to remove it? I've tried WD-40 hoping it would seep into the threads, but no joy. I have a bottle of CRC Freeze Off on order hoping I might be able to shrink it just enough with cold temps to break the bond. I'd appreciate thoughts from others who have run into something similar.