Fuel flow testing and fuel tank calibration
This post covers a couple different shop sessions. Four major things accomplished. 1. Fuel flow testing 2. Fuel tank calibration 3. Fuel pressure testing, and 4. Fuel sender calibration.
The first step was to calibrate the set points on the RED Avionics (formerly Princeton) fuel senders. Once the empty set point was obtained, we removed the fuel hose from the servo and using the boost pump ran fuel flow tests in 3 different attitudes. Nose high. Level flight. And nose low. The fuel test results greatly exceeded the FAA required 125% of maximum required fuel flow (15.6 mph for this engine). Also – there was very little unusable fuel amounts.
Next we reconnected the fuel hose and ran a fuel pressure test. I immediately heard a leak. Oh no!! With my brain fully disengaged, I called Mike. His first question “is your mixture full forward?” BAH! What a dumbass. Of course mixture was full forward. I was dumping fuel into the cylinders. Well. The good news? It was a good test of my sniffle valve! With the mixture at ICO – the pressure was where it needed to be, and stayed that way.
Lastly I calibrated the fuel tanks in both the flight attitude and taxi attitude using the G3x. This took FOREVER. Filling tanks is quick. But draining the tanks solo… well it took about 9 min to drain 2 gal. So… with 42 gallons plus fill and calibrate time. Yeah. It took awhile.
My buddy Brian was on hand to help with the fuel flow testing. His clear fuel can was an absolute life saver. He found my excessive static protection hilarious. But I’m not taking any chances! I grounded the plane to the hangar, and i ran a wire into each drain can to ensure everything was at the same potential.
And keep a hand on the plane!!