Cross Feed loss of fuel from vent??

[atsiii]

Hello, everyone.

Question: Does anyone know anything about a history or tendency of Skymasters (either suspected or proven) to cross feed fuel from the uphill main tank, and dump fuel out the vent of the downhill main tank-- when left parked on a relatively mild cross slope and the selectors are not turned off? Any experience or insights, or recommendations about where I might research this topic, would be greatly appreciated.

Allen