Starting Fuel Lines

Since I’ll be on the way to Oshkosh shortly, I wanted to spend some time figuring out the fuel and brake systems again. This will allow me to buy the few remaining parts that I don’t have. I have had some 3/8″ .035 5052-0 line for a while, but I figured I should try bending and flaring some before I go to OSH in case I need to pick up more spares of that too. My first realization is that the 5052 work hardens really well- so well that I really only get to bend it once. If I bend it to 90 degrees when in fact I only needed 88 degrees, It’s pretty much impossible to bend it back to 88 again. This meant that I had quite a learning curve and made a few pieces of silver macaroni. I remembered the trick that Tony B suggested and tried making some templates out of welding rod first, and that helped.

One of the requirements of the fuel system is that everything flows downhill to the gascolator. Since the door jamb that the T fitting bolts to is sloped aft, this would create a low spot where water could be trapped.

Fuel Fitting Angle

This would be the fitting of the angle without any shims.

I wanted to try to eliminate this problem by making shims to angle the fitting closer to level.
A better angle

Here's a better angle for the fitting.

Another idea

This idea didn't work.

Aluminum shim attempt

Here's the making of an aluminum shim. This one turned out to be too thin at just 1/8 inch.

Shim concept

Even though these are too thin, you can see how they would work.

With that operation tabled pending some thicker aluminum, I started working on getting the fuel valve in the right place. This isn’t supposed to be hard, but it isn’t going well. As pretty and nice as the Andair valve is, the problem is that the outlet is on the bottom. Even with an angle fitting on the bottom, it is a little bit too tall. In order to keep a downhill slope from the valve to the gascolator, the valve has to be a few inches forward of the gascolator.
Locating the fuel valve

Locating the fuel valve

Another note from the future- I’ve decided not to use this fuel valve. There is another option that is much better suited to this type of installation. The other valve doesn’t have an outlet on the bottom, and the inlets are situated lower, so it will not protrude below the stringers.

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Hours Logged This Session: 5.7
Total Hours: 1883.75

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