Humbly I will admit I'm no grease monkey and don't have the pedigree to troubleshoot most issues with my boat (or any other vehicle for that matter). Have a 2009 GTR35 (briggs) with <200 hours on it. Runs great in cool/cold duck huntin weather. Runs great on any day trips any other time of year out of the garage. Runs great when we bring it down the shore for summer vacation (running in back bays of South Jersey fishin and crabbin) for the first day or two of the week. Now, for past two summers, we have had the same thing happen: later in week the motor will not run smoothly, no propulsion, and spits/sputters like its got bad gas. If you've ever waken up at the Jersey shore, the humidity over night is about 110% and everything is soaked like it rained even when it didn't. I keep the fuel tank tucked up under the front deck of the boat, but I assume that moisture is getting into the fuel, carb or both. I run sea foam in my fuel normally and NEVER let the gas sit more than a couple days, let alone weeks. This week, while down the shore and after the motor took a crap on day 4 of our trip, I bought a new gas can and connectors to rule that out ($100 experiment that didn't solve anything). When I get home, store it in the garage for a week drying it out, and swap out the gas, I'm fairly confident it will run like a top again. Anybody have this happen to them? Any solution to prevent this in the future?