..Blueskies. wrote:
: I never have had any water drain from the sumps of the 172 even after many many gallons of mogas (never any alcohol in
: it btw), but it seems every time in put in avgas there are some little water bubbles at the bottom. Makes me wonder...

Wow... my experience is exactly the opposite. I only ran mogas without the water-absorbing spin-on filter for
a few weeks, but every time I would collect a few drops in the sump. Even with my separator, I get just a drop or two
of mogas, with a few specs of what looks like rust floating in the water but underneath the gasoline. I check for
alcohol a few times a year, although I was assured by the supplier to the service station I religiously get my fuel
from that there is no alcohol blended in. A few times a year assures against winter/summer mix.

Although I am disturbed by the existence of any contamination at all, it is always small and only in the fuel
tank sump drains. I have never found anything in the gascolator (sorry... not familiar with the 172 setup... I've got
one per wing tank and common gravity-filter gascolator before the carb).

100LL has always been squeaky clean for both water and particulates.

-Cory


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* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
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