[oldbluesplayer]

Well, I'm not sure how it's getting in, but it should only have two choices - fill and vent - so double check that cap - even with the new o-ring it might not be seating right, also check your vent - it's not angled up, is it ? Is the vent line lying in the bilge, in water, when it rains? if that was the case, and it had a crack, it could let water into the tank.

My next thought is that it sounds like you don't have a water seperating fuel filter, and probably ought to install one.

Another thought, is the new E-10 gas - from what I've read on this stuff, it hold much more water in suspension, than the old gas, but when the limit is exceeded, it dumps it all out of suspension - how much do you use the boat? how long between fill-ups, how long between those three times you got towed in ?

just random thoughts

Bill