May 18, 2007 - Fuel Vent Lines
Bruce and I had planned to take this Friday off so that we could fly the Citabria to the Mid-Atlantic Fly-In at Lumberton, NC (KLBT).  Alas, it was not to be.  The weather for most of the day was Very marginal VFR all the way to Norfolk.  We didn't feel like scud running all day so we cancelled the flight.

I hadn't worked on the RV much this week so I decided to spend the day on the RV and knock out the fuel tubing.  I started out by fashioning the vent fittings.  Searching the Vans Air Force forums, I liked the way  XXX did his vents so that's how I did mine.  First I cut a 45 degree bend fitting with the band saw. 

Then I put it in the drill press -- wrapping the threads with masking tape to protect them -- and ran a file along the side to remove the bottom threads.  Finally, I filed along each side so that I could put a wrench on the bottom part for tightening. 
With the bottom floor vent fitting in, I was able to measure and cut the tubing in preparation for flaring. 
I flared the aft side without incident.
But when I went to flare the front side, because of the bends and the sleeve, I didn't have enough "real-estate" to use the flare tool.  I tried anyway with no joy.  Notice the crack in the sleeve and the mangled tubing.  Nothing to do but redo the entire thing.
Of course, things went much faster the second time.  I made sure I had plenty of "real-estate" to flare the ends.  I figure if I have 1 1/4" of straight tubing, I'm good to go.  The left side is done.
Right side done. 
Next on tap were the fuel lines that run from the wing tanks, into the fuse, along the main spar, to the fuel selector control valve in the middle.  To do that I had to work on the fuel selector apparatus.  Here, I'm drilling the holes in the plate.  The starter holes are pre-drilled.  I just have to open them up per the drawings.
I made the aluminum tube spacers per the drawings, then trial fit the selector valve.  Of all things, I had the most trouble just getting the lever off.  Yes, I removed the retaining screw first.  The thing just wouldn't come off.  I finally put the valve in the vise, put a little block of wood against the lever, and tapped it a couple of times with a hammer.  Once off, I grinded off the little arrow off the front of the lever.  I temporarily screwed in all the aluminum fittings.
I screwed the fuel selector plate to the main spar.  Then I tried using a coat hangar wire to get a feel for how long the fuel line tubing had to be.  The fuel line tubing is 3/8" and a lot harder to bend than the 1/4" tubing for the vent line.  Looking at all the bends that would be required, I had no idea how I was going to do this.  Everything I could think of would not work.  I decided to sleep on it. 
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