Sat Feb 26 2011

Fuel line tubing

Snicker's kept me company while I used up the last of the first 50 ft. roll of tubing. This one should be a good fit for the right side of the fuselage. I'll have to wait until my Aircraft Spruce order comes in before I can do the left side.

Next, it was on to make up the connection between the fuel selector valve (center port) and the Airflow Performance fuel filter. After taking careful measurments of the location of both the termination points as well as the Adel clamp location under the pump / filter mounting plate, I designed it in SolidWorks and bent one up. Since this is a short piece of tubing, I was able to make it from a straight section of one of the scrap right outboard tubing sections.

So far, so good. It fits the fuel valve and the Adel clamp. Let's see how it fits up to the fuel filter...

Sweet! It fits great! Could it be that I actually got one piece of tubing right on the first try! W00t!

Unfortunately, my elation was short-lived. I realized I had forgotten to leave space for the swivel tee attachment to the fuel selector. The side port on this tee goes to the bypass check valve on the fuel pump manifold. So, if anything causes the pump to fail or the filter to become clogged, the engine will still get fuel.

I was hoping that I had enough of a straight section on the downward leg of my existing tubing that I could just shorten it to make room for the tee. After measuring the length of the tee, I was only going to have about a .8 inch long straight section. I thought that might be a bit short, so I trimmed a piece of scrap (that had a 90 degree elbow) to that length and checked whether my flaring tool could get enough of a bite on the tubing. Nope. :-/