Takes a village... flaring fuel lines
TLDR
- Made 2 flared fuel line fo boost pump
Details
So previously I found that the rigid tube connecting the boost pumps to the fuel tank are leaking, I worked on making 2 new rigid tubes o replace the bad flare lines today.
The parts looked very simple. It’s a very small tube (3 inches maybe) with AN6 fittings on each end. But it took a lot of time to get them done.
Tools:
I needed a flaring tool. The tool is available on aircraft spruce. A nice one is about $150. I (hopefully) only need to use a once so a nice fellow builder from my local EAA chapter lent his to me. I got the flaring tool and some greasing oil from him earlier this week.
Flaring:
I cut some tubes to practice, then started to make real ones. The surface is definitely more smooth than the factory ones. I am confident the previous leak was due to the bad finish on the flaring.
Testing again:
I connected one of the new flared tubes to the left wing and pumped the tank with air. However I still see some tiny bubbles coming out.
Expert guidance:
Just as I was frustrated on the seal, my local EAA chapter’s president (also my hangar neighbor) came by and took a look at my work. I got a few pointers from him:
- The flaring on my tubes was a tiny bit too short.
- After using the “quarter turn” method to torque the AN fittings, I can turn the fitting tiny bit more to see if seals any leak.
So I decided to do #2 first, then redo the tubes if it doesn’t fit the problem. Fortunately, turning the fittings a bit more seemed to have worked!!
So for now I’m going to leave the tubes as is, and consider the entire wing/boost pump work as complete. Hopefully I don’t need to worry about the wings until the final assembly.
In the end, a 5 hour job turned into multiple weeks and involving several people. I am continuing to learn new things each day. I’m so glad I have this much help along the way. Building airplanes really does take a village!
End result
