I started flying in about 1969. I have flown several thousand hours by myself
and with friends. During fuel checks before flight from fuel tank drain tests I
have never seen water come out in the little tiny test before flight. That did
not mean there was no water in there somewhere. One thing that got my attention
many years ago was an article that I read in one of the flying magazines on
this subject. The writers of the article had conducted tests on several
different kinds of airplanes, highwing, low wing . They reported in the article
that in some cases they drained 2 or 3 or more gallons of fuel out of the wing
tanks before any water would come out. If you think about your flight training,
the instructor gave you the little glass test tube and just a few ounces of
fuel were drained into it, then you would look at it to see if any water was in
the bottom of the test tube. I personally have never seen any with that test,
then of course you were to throw/dump that sample down on the ground. I always
thought that was a waste of fuel, and certainly do now, heck that would be 50
cents worth now ! The gascolator is the last defense before the fuel gets to
your engine, so yes the gascolator should be drained on a regular basis. For
you who are buying auto fuel, then dumping it into your fuel tank might want to
think about purchasing one of the funnels that are available that have a screen
built into them that is capable of filtering water out of your fuel. You would
at least know then that you had not dumped water accidentally into your tank.
The same funnel can be used even if you are buying gas at an FBO, just put fuel
nozzle into the funnel to fill your tanks. I have one that I carried in my
Mooney to fill my plane, just in case of course !
Larry H.
