The fuel load should not change in the header tank, as it should be kept full by the action of the fuel pump - supplying excess fuel, and overflowing back into the wing tank. Only when the fuel pump fails, or you run dry in the wing tanks, would the header tank begin to loose fuel - as it gravity feeds the engine. Time to land...soon.Whenever the header tank float begins to drop, find an airport.
Fly safe - Have fun Harry Francis 93530 Blacksburg, Va.
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