Working On Fuel Lines

I've almost finished the fuel lines in the cockpit along with the fuel selector. There are two tanks, one in each wing. The tank that feeds the engine is selected with the valve shown in the picture below. I've temporarily removed the pointer during installation of the lines but you can see the brass valve below the plate and the shaft sticking out above it where the pointer attaches.

The selection of the fuel tank is not automatic for several reasons. If they were interconnected, you couldn't stop a fuel leak from draining both tanks or if one tank had contaminated fuel, it might contaminate both. Also, with lower compression aircraft engines, you can safely burn auto gas which is cheaper but doesn't have the same energy as aviation fuel. Some folks will put auto gas in one tank but only use it during cruise flight and use the aviation fuel for takeoff and landing.