I have about 15 hours on my 9A and came across one of those "gotcha's" today. I have been making mostly short flights and have yet to fill my tanks above 12 gal. each. Most flying has been done on the left tank, for whatever reason.
Yesterday on a 1.9 hr flight, I noticed my fuel pressure was a little low, off maybe 1 psi while on the right tank. I kicked on the electrical pump and the pressure came up to normal, but I decided to switch to the left and head back home. Today I thought I'd check everything out. It didn't take long to know I had a problem, as when I opened the right tank cap, pressure escaped! It was warm and the pressure was no doubt due to vapor pressure, but there was no venting.
I started checking lines and isolated the problem as the line inside the tank. A mirror check of the inside end revealed no pro-seal, which was my first thought. Then I pulled the coupling next to the fuse. It was plugged by a bug of some sort. It had to have been plugged between finishing the wings and mounting them. I "vacuumed" out the line and flushed it with carb cleaner from the tank end toward the inboard end.
I don't know how I missed this when I mounted the wings, but on my next build, I will cap the lines better. Something like that could really spoil your day. You might consider adding this to your pre-final assembly checklist.
Bob Kelly
Yesterday on a 1.9 hr flight, I noticed my fuel pressure was a little low, off maybe 1 psi while on the right tank. I kicked on the electrical pump and the pressure came up to normal, but I decided to switch to the left and head back home. Today I thought I'd check everything out. It didn't take long to know I had a problem, as when I opened the right tank cap, pressure escaped! It was warm and the pressure was no doubt due to vapor pressure, but there was no venting.
I started checking lines and isolated the problem as the line inside the tank. A mirror check of the inside end revealed no pro-seal, which was my first thought. Then I pulled the coupling next to the fuse. It was plugged by a bug of some sort. It had to have been plugged between finishing the wings and mounting them. I "vacuumed" out the line and flushed it with carb cleaner from the tank end toward the inboard end.
I don't know how I missed this when I mounted the wings, but on my next build, I will cap the lines better. Something like that could really spoil your day. You might consider adding this to your pre-final assembly checklist.
Bob Kelly