The Cessna 120-140 Association Forum

Hi All
I am interested in adding an aluminum fuel tank skins on a fabric wing 140. It looks like it should be straight forward structurally. just add #8 platenuts on the inboard and outboard ribs, and front and rear spars. I would plan to use a similar number and type of fasteners as the 140A uses for a similar cover arrangement. I would also add some diagonal supports for the outboard tank rib to support fabric tension, similar to how Piper does it... Am I missing something. Yes I know I am fixing something that isn't broken, but IF I ever need to get to the tank..... Does anyone have a sample 337, or field approval that I could get a copy of for this mod? If anyone knows the N# of a 140 with this mod, I can order a CD of the paperwork from the FAA.

Thanks for any help

John Groeneveld
N76256 four years into a total restoration

I've wondered why they are not accessible too? We put new tanks in a PA-12 restoration 18 years ago and they have been removed twice for leaks. Thinking our tanks are better construction process and maybe heavier material? anyway knock on wood mine are good and no need to overthink it? PS still planning on flying down but finding time is a pain in my a_ _ Build on JEFF