Carburetor corrosion

[buba]

I live in Brazil and I use a Yamaha F15AMHS outboard, purchased in Nov 2004, model 2005.
Our fuel is a mixture of gazoline, ethanol and many other odd substances, including shit.
This horrible mixture corroded my carburetor and the fuel pump in a question of months, causing erratic function of the motor. Is there a brand of a carburetor I could use with this fuel?

[boats.net]

No I'm not aware of any other carb that would work. Have you tried adding a fuel/water separtor filter in fuel line before the engine?