“In my research this season, I came across a bit of information I thought was worth sharing. The Boat Owners Association of The United States (BoatUS) has some tips learned from fuel industry insiders on how to store a boat with E-10 gasoline (containing 10 percent ethanol) over the winter.
The octane issue: Some boaters choose to leave their boats’ gas tanks mostly empty over the winter, and then refill in the spring in the hopes of “refreshing” the fuel to regain any octane loss. However, a nearly empty gas tank introduces a bigger problem: the strong possibility of phase separation with the E-10 gas. Incidentally, over long winter storage periods, E-10 gasoline loses octane at about the same rate as non-ethanol gasoline.”
Read more about this issue here.
It is suggested that you leave your fuel tank nearly full to avoid phase separation. An additive should help keep the fuel fresh during that time. Also, do not close the fuel tank vent as that can lead to dangerous pressure build-up.
If your outboard engine is having fuel-related issues, contact Robbinsdale Marine at 763-533-0300. Our team is very familiar with troubleshooting these problems and can have your engine performing the way it should again.