Re: Full fuel tank or not for the winter
For what it's worth, Mercury recommends running the tank empty(when possible) if ethenol has been used and filling it if not. Guess the ethenol attracts moisture and better to drain it for the winter...
What should be done when storing boats with ethanol-blended fuels for extended periods?
When preparing to store a boat for extended periods of two months or more, it is best to completely remove all fuel from the tank. If it is difficult or not possible to remove the fuel, maintaining a full tank of fuel with a fuel stabilizer added to provide fuel stability and corrosion protection is recommended. A partially full tank is not recommended because the void space above the fuel allows air movement that can bring in water through condensation as the temperature cycles up and down. This condensation potentially becomes a problem. Mercury Marine Fuel System Treatment & Stabilizer can help maintain fuel systems in storage. It contains oxidation inhibitors to reduce oxidation and gum formation, metal chelating agents to protect metal components from corrosion, water absorbing agents to reduce the presence of free water, and dispersants to help suspend and disperse debris. It is best used by adding to the tank at the recommended dosage, running the engine for 10 minutes to allow the system to be cleaned, shutting off the fuel valve to interrupt the fuel supply and allow the engine to run until it stops, topping off the tank until its full, and capping any openings to reduce the amount of exchange with the air that might bring in condensation.
