Sea foam

I also add a big can of Seafoam 2x year to clean things up in the fuel system and engine,

Seafoam I really heard nothing good out of..
I used to do the K100 ..

I run alot of hobbies.. 20 + snowmobiles.. 11 atv's, 6 waverunners and 9 boats, from a 13 foot bullet to a 50 foot Cary.. EVERYTHING IS STARTRONNED !!!! I have the west marine port supply card thats were I get it from, I swear by this stuff... IT HELPS,,, BUT DOES NOT CURE..

I store with Seafoam also. Boats, sleds, etc and have had good luck. For those of you that think there's no ethenol in your gas you may want to test it. I was told the same but when I tested it sure enough it had ethenol.

I have no idea. I just noticed that it seemed like none of my stuff running 2 stroke fuel (weed wackers and such) did not have any issues. So I have been adding it in and so far no issues. I have no other proof then I have not had any issues since. It may be coincidence maybe not. When it lets me down I will try something else.

Startron here as well.
Stratron and StaBil for winter storage.

I used Sta-Bil marine formula every year since 2004 in my boats. I fill tanks in Oct-Nov with full dose Sta-Bil then fog the engines and they all start beautifully in Apr-May. However this year I emptied the Fountain of 250 gals. leftover gas (see my thread on "Gas Caddies") and used it in our cars. All 4 tanks are now as empty as I can get them without removing the gauge sender. I am going to see what happens with these empty tanks over the winter. I am leaving the fuel removal pump in place to remove anything that might be there in the spring (condensation, etc.).

Star-tron.....you can get it at walmart for about $8.00 a bottle that should do a full tank in most anyone's boat here.

I use it all the time. Never had an ethanol related issue.

My father does not listen and never adds it, always rebuilding carbs, pumping out fuel tanks. But who am I to try and teach an old dog right?

I too use star tron for winter layup, I go thru my gas too fast to worry about it in the summer

The article, below, appeared in BoatUS Magazine...

Three Ethanol Myths Clarified
By Bob Adriance

It's time we get to the bottom of how E10 is affecting our engines

In the few years since ethanol began to be widely used in the United States, a lot has been written about its properties, the problems it's created, and how to best cope with its possible effects. Some of the advice has been based on science, some on hearsay. While E10 is not an ideal fuel – and E15 could cause serious problems for marine engines – at least a few myths about ethanol have arisen with the potential to do more harm than good:



Myth #1: Ethanol-enhanced gasoline (E10) loses octane much faster than regular gasoline.
Many mechanics believe that octane loss during winter storage could be great enough to damage an engine when it's run in the spring. These same mechanics will often recommend leaving the tank almost empty so that fresh gasoline can be added in the spring to raise depleted octane levels. While all gasoline loses octane as it ages, ethanol-enhanced gasoline loses octane at about the same rate as regular gasoline, according to Jim Simnick, a technical advisor at BP Global Fuels Technology, and Lew Gibbs, a senior engineering consultant and Chevron Fellow. The two men have over 75 years of combined experience working with gasoline and both agree that the loss of octane over the winter would not be sufficient to damage an engine. Note, however, to keep any gasoline, including E10, as fresh as possible; they said it's good practice to always add fuel stabilizer — an antioxidant — whenever the boat will be idle for long periods.

The recommendation to leave a tank mostly empty is bad advice; it could significantly increase the amount of water that gets into the tank. When enough water enters through the vent, the ethanol will separate ("phase separate") from the gasoline. Leaving a tank mostly empty does three things to increase the chances of phase separation:

It increases the volume of open space in the tank (its "lung capacity") so it can "breathe in" damaging moist air. An almost-empty tank leaves more space on tank walls for condensation to form. Leaving less gasoline in the tank means there will be less ethanol to absorb the condensation.

It's interesting to note that in areas of the Midwest that have been dealing with E10 for over a decade, topping off tanks is common practice. (As an alternative, completely emptying the tank would eliminate any chance of phase separation.)

If phase separation occurs, the highly corrosive ethanol/water mixture will settle to the bottom of the tank and remain there even after fresh fuel is added in the spring. The only way to remedy the problem would then be to drain the tank and add fresh gasoline. The best way to avoid phase separation over the winter (aside from emptying the tank) is to leave the tank 95-percent full (which allows for expansion) so that there's less moist air in the tank, less space for condensation to collect, and more gasoline to absorb whatever moisture does accumulate.


Myth #2: E10 attracts water, so it's important to install a water separator to prevent the water reaching the engine.
Mercury Marine, which recently hosted a Webinar on ethanol myths, noted that ethanol does not "grab water molecules out of the air." It is hydrophilic, which means ethanol holds water. With regular gasoline (E0) as well at E10, the primary cause of water collecting in tanks is condensation on tank walls. But unlike E0, which can absorb almost no moisture, E10 can hold up to half of one percent of water by volume, and the water molecules will dissolve in the fuel. The "solubilized" water will bypass the water separator and burn harmlessly through the engine. Only if phase separation were to occur would a water separator do its job, but by then the fuel itself would be the problem. The phase-separated water/ethanol mixture would settle on the bottom of the tank near the fuel pick-up and would quickly stall out or even damage your engine. And because ethanol is used to boost octane, the remaining (low-octane) gasoline at the top of the tank would also have the potential to damage your engine.

Note, however, that a fuel filter (10-micron) is essential to keep gunk from reaching your engine. Ethanol is a solvent that dissolves resins, rust, and dirt that have accumulated on older tank walls. Especially when you first make the transition to E10, it's important to carry spare filters and a galvanized bucket to store used filters prior to disposal. Even in new engines and tanks, E10 will sometimes form a mysterious gooey substance that will also clog filters. Richard Kolb, the manager of Emissions and Regulations for Volvo Penta, believes the goo is caused by water mixing with one or more of the 108 approved compounds that can be used in gasoline. These compounds vary among suppliers, so one solution is to change to a different brand of gasoline. Another is to use carburetor cleaner, which he says has sometimes remedied the problem.


Myth #3: Certain additives can prevent phase separation?
Both Gibbs and Simnick said that the additives that eliminate water may work incrementally to protect against phase separation, but Joe Simnick stressed that no additives will stand up to a good slug of water. Lew Gibbs added that the best way to prevent phase separation in E10 is to "keep it dry, keep it dry, keep it dry." That means keeping the tank filled to prevent condensation. Mercury Marine has also noted that, contrary to statements made by some companies that produce fuel additives, there are no additives that can make stale or phase-separated gasoline usable.

E10 is certainly not as trouble-free as E0, especially the first few tankfulls. But for newer engines, those built after about 1991, there's no reason the initial problems can't be overcome. No less an authority than Mercury Marine says, "After the transition period from E0, E10 may actually be a superior marine fuel as it tends to keep low levels of water moving through the fuel system, keeping the
system 'dry.'"

Bob Adriance is Editor of Seaworthy, the BoatUS Marine Insurance damage-avoidance publication, and author of Seaworthy, Essential Lessons of Things Gone Wrong (published by International Marine/McGraw Hill, available at www.Amazon.com and major bookstores).