Pontoon Boat & Deck Boat Forum

For winter storage in Ohio is it best to top off large gas tank with fuel and stabilizer or leave tank low? The boat is kept in an un-heated garage car port. Last year it was stored full. I was thinking if I only kept half tank of fuel there would be room for condensation to developed.? Any thoughts? Its a large gas tank on a 2012 sun tracker. Its got a 9.9 mercury and it sips gas and I can't seem to run it all out. Thanks! Pete in Ohio valley

I add a stabilizer and run it close to empty and in the spring top off and go, but i use 6 gal tanks with my 15 hp, and if your useing one of the 20 to 30 gal main tanks i would add a stabilizer all of the time being as a full tank can last all year.

MH Hawker wrote:I add a stabilizer and run it close to empty and in the spring top off and go, but i use 6 gal tanks with my 15 hp, and if your useing one of the 20 to 30 gal main tanks i would add a stabilizer all of the time being as a full tank can last all year.

Yep! and welcome!

I'm a believer in filling it full and adding stabil, simply for the fact that an empty tank can get condensation in it from outside temp changes. I fill my lawnmowers, wood splitter, all my fuel containers even my weed eater. I use the Stabil Ethanol treatment in everything that gets ethanol ran through it. Been doing it the boats for 30+ years and never a spring start up fuel issue!

+1 on a full tank and stabilizer.

Yep full tank n stanlizer

cwag911 wrote:+1 on a full tank and stabilizer.

+2

cwag911 wrote:+1 on a full tank and stabilizer.

+3

The more gas you have in your tank the longer it will take to separate, regular marine fuel or E10/15.

The guy I buy my gas from for my tank at home has told me that, he used to work at BP. It isn't made the same like it was many many years ago. With all the additives they put into it now, it starts to separate after about 2 - 3 weeks of sitting.

So +4 keep full and add seafoam/stable.

I don't think that it makes that much difference anymore with most tanks being made of plastic. I have done it both ways and no difference. I think it is the Seafoam or whatever you use. Its just important to just remember to add it to the tank.

Yep ditto x3 for me too, full tank, add stabilizer and we use non-ethanol marine gas, never had a issue in the spring for the past 15 years.

we use non-ethanol

That is the answer! Stabilizer is good but non- ethanol is the trick.

Non ethanol gas is way better in most all applications but it still can suffer from degradation over time. I use only non ethanol and Startron stabilizer in all my boats, mowers, blowers, etc. and have had 0 issues with 6 month and longer layups over many years. Years ago I had an old 1983 inline 6 Mercury 90 HP that ran like crap until I started using the Startron. One dose (1 ounce per 16 gallons of gas) and I was a believer.

A good source for your non ethanol gas stations:

http://pure-gas.org/

Thanks for all the info! I was able to find a station close to get the 90 octane ethanol free and then added that marine stabilizer. Thanks for the link on ethanol fee stations!

while we're on the topic I have a question I hope you guys can answer. It is my understanding ( very limited knowledge of these things ) that if your fuel tank is made of metal you should always fill your tank up before storing for the winter.. this supposedly reduces the chance of condensation / water in the tank right? what if your fuel tank is plastic.. will condensation still form in a plastic tank? I'm not sure but I believe the tank on my benny 20SFI is plastic. In the past I have always filled the tank up and added stabilizer and so far no problem. But now as the end to the boating season nears, I still have about a half tank of fuel left.. I don't plan to drain it.. might add some more stabilizer... but in this particular case would I be better to fill her up at the end of the season, or wait til spring and top her off with fresh fuel.. oh, forgot to mention, the fuel in my boat now, and the only fuel I put it is ethanol free.... appreciate your help. thanks guys.