Today I tested the fuel system for the first time, running the electrical fuel pump and testing fuel flow. Everything worked well, and I was happy to see no obvious leaks.
I started by disconnecting the fuel line leading into the fuel servo, and redirected it into a large measuring jug. Then I poured approximately three gallons of gas into the left fuel tank, and turned the fuel selector to the left tank. I wanted to make sure I had fuel in the fuel pump before starting it the first time, so I used the shop vac and some clear tubing to prime the system – drawing fuel through the fuel lines, all the way to the fuel servo.
I powered up the panel and switched on the pump, and was happy to see fuel flowing into the jug. I ran the pump for a minute and measured 92 fluid ounces pumped, which translates to 43.125 gallons per hour. I repeated the test on the right tank, measuring 94 ounces pumped, about 44 gallons per hour. During the second test the fuel flow gauge was measuring 43.7 gallons per hour, which is very close to the amount I measured.
I repeated the test in a level flight attitude, and then tested for unusable fuel. With the plane in a level attitude, I pumped all the fuel out of the tank, and then drained the leftover fuel from the fuel tank drain port. I measured 6 ounces of unusable fuel per tank, for a total of 12 ounces.
