1. Fuel tank Vent blocked
creating vacuum in the tank
(Why is there no "crossfeed vent" between upper tanks? or
valve between vapor return lines? Or is there?)
2. Negative/zero G's exposing the tank gravity feed outlet to air (okay
mostly
N2, but still N2 Vapor).
3.
Vapor in the lines before the selector Valve
4. Vapor leaking past the fuel selector Valve O-rings
from the
pressurized cabin
5. Vapor in the line feeding the EDFP around the accessory case
especially in a hot climb
6. Vapor anywhere else the fuel line runs next to a heat
source, though
less likely in the higher pressure areas. ( Anybody have a triple point
chart
for 100LL? Marv has a nice graph on 2/2/07
-- but no pressure axis or contour/family of curves... yet )
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