Harmut and Fred, Many thanks for your input. The fuel tank caps on these 15 gallon tanks do not resemble the original wing tank caps. They have a ridge bisecting it and when tightened, the ridge runs parallel to the wing cord. A perpendicular hole runs through the ridge. This hole opens into the top of the cap. When you hold the fuel cap up to the light, you can see that they it is wide open (i.e. it is a rather large opening and easily visualized). Regardless, we ( myself and the 2 APs - both are also IAs) have blown compressed air through the vent hole several different times.
Thanks again, David --- In [email protected], "drdlhammond" <drdlhamm...@...> wrote: > > I have a 1967 Alon A-2 Aircoupe in which the previous owner removed the > header tank and replaced the 7.5 gallon wing tanks with the 15 gallon units. > I have flown this plane for the past 1.5 years with no problems until lately. > I have noticed that during flight, the right wing tank does not empty (i.e. > after a flight, the left wing tank fuel level is down while the right wing > tank fuel level remains at the same level as when the flight was initiated). > > The fuel cap vents are patent (checked multiple times). I have had two AP > mechanics inspect the fuel lines and fuel line/tank strainer - all clean. > While the airplane is sitting on the ground, the fuel freely drains from the > right wing tank. In fact, fuel can be placed only in the right tank and > after sitting for a short period of time, the fuel transfers to the left tank > until the two tank levels are even. This was not a problem until just > recently. > > Has anyone had similar experiences with the 15 gallon wing tanks? Any > suggestions? > > Thanks, > David >
