Let's say you are taxing over to the pump, when do you sump? Does it matter if the plane is hangared or not?
Textbook answer is to sump all both tanks and gascolator before engine start. That will get rid and any dirt or water that might have been blown into the gas tanks while it has been sitting for weeks or months since the last flight. Then after fueling, wait 5 mins for sediment to settle and sump the tanks before take off.
I have been doing this for years, but I notice no one else sumping after buying gas. Waiting 5 mins for stuff to settle means you may be block traffic into the pump. If you taxi away from the pump area, it kind of defeats the idea of preventing contaminants from getting into the engine.
Textbook answer is to sump all both tanks and gascolator before engine start. That will get rid and any dirt or water that might have been blown into the gas tanks while it has been sitting for weeks or months since the last flight. Then after fueling, wait 5 mins for sediment to settle and sump the tanks before take off.
I have been doing this for years, but I notice no one else sumping after buying gas. Waiting 5 mins for stuff to settle means you may be block traffic into the pump. If you taxi away from the pump area, it kind of defeats the idea of preventing contaminants from getting into the engine.
