Yamaha 2000 fuel filters

I have been struggling with jets on the carbs getting clogged with small particals of unknown material. I am using the Yamaha 10 micron filter with another water/fuel filter. I also understand the the engine has a filter then each carb has a filter. How is it possible for anything to make it through the filter maze? could it be something after the filters? The tank is not an issue as it is a 2000 plastic tank and the boat mfg has assured me that it is ok. I love my F100 when it is running right.

[robert graham]

I believe some of these particals form in the carbs when the fuel sits in them for several weeks. drain the carbs onto a clean white rag several times per year and while you have the drain plugs out, pump the primer bulb to 'flush out" float chambers, then replace plugs and leave float chambers empty. use Stabil Marine all the time but especially when motor won't be run for a while. that with your fuel/water seperator and you should be home free on fuel related problems. my motor is a 1999 Yamaha 90C and the carbs have never been cleaned and motor runs like new all the time.