Hi Guys
I have a Vixen that just yesterday flipped past the 500 hour (master switch time) and in the last 400 hours has never had any filtering other than the gascolator (required by Transport Canada on all a/c except ultralights). I purchase off hiway "non ethanol" fuel from a bulk dealer except when traveling and 100LL is all that is available. To date I have never had an issue with fuel contamination and hopefully won`t have because most of our terrain here is quite unfriendly!
Not sure, but I would think that anything passing the fine screen in the gascolator would also pass through the carbs.
I did install the recommended fuel return line (back to the gascolator) and a fuel pressure gauge (runs just under 5 PSI).
Cheers
Don
Vixen 912UL C-FOXK