Phase separation, ie. Watery fuel

I just want to thank everyone for your comments and advice.  I have the plane with my mechanic and I'll let you know the diagnosis.  The slimy goo in the sample I took threw me for a loop.  I've never seen anything like it, and my thought is that it clogged up the filter just as some of you said.  It was quite possibly biological/microbial.  I wish I had taken a picture!

Steve Hirschi, what type of filters do you use?  I like the idea of see through. Thanks!

Hengst H 102 WK, Hengst H 103WK & Baldwin BF7863.  

 As used by a large number of European recreational light aircraft builders, power by Rotax engines.

High quality, gauze (not pleated paper), in line, light weight, leak free, almost indestructible, transparent fuel filters and relatively cheap (if you buy in bulk). 

A few more Baldwin products for your consideration (all have BF before number):

 7850 (very large filter area) : 7725 ; 9906 : 45000

and if, by chance, you have the same size fuel cap:

PF 46103 might help prevent contaminants entering fuel tank. 

NOTE; It is remarkable hard to get actual filtration standards (MU particle/gauze size) from most of the filter suppliers.

I see slimy goo too sometimes, but 9 times out of 10 it's a silicone based product that doesn't desolve in fuel. What maintenance was done before this happened?

In diesel applications, the biologicals live in the water and feed off the hydrocarbons unless a Biocide is present.

With ethanol fuel, the initial water is absorbed into the fuel until phase separation occurs.
The separated "Water" contains a lot of ethanol; a natural biocide.
There are few life forms, if any, that can live in any significant concentration of Ethanol or most any other Alcohol.

0.08% is considered legally Drunk in most states.
0.50% is considered Fatal in most situations.
5% would be considered Fatal many times over for most organisms.