Gas Stabilizer Over Winter

[denmanislander]

I have two 60 gallon gas tanks for my twin 5.7 Mercruisers on my 10 m Cooper Prowler. Do I need to put stabilizer in the tanks for the winter? She is staying in the water at a government dock. If I do put stabilizer in, should I run some through the engines to keep the carbs clean? If it matters, it doesn't get very cold here.
Thanks...

[Solitude]

I use a product called seafoam.

[CalebD]

Yes.
A stabilizer is a good thing particularly if there is Ethynol mixed in with your gas.
I use a product called Sta-Bil that seems to work well with our E10 gasoline.

[Hud3]

Yes, absolutely! And top up the tanks to reduce airspace where condensation could introduce water to the tanks.

[scubasteve]

With ethynol i use both MDR's E-Zorb and StarBrite's Startron. E-Zorb claims to keep water from causing phase separation of the Ethanol. Startron helps keep any microbes from growing and also acts as a stabilizer.

Prior to using ethynol i stuck with stabil.

[Firehoser75]

Denman,
Stabilizing fuel that will not be used in the time period of a few months is necessary, especially if it is gasoline and not diesel. Gas will decompose over time and cause gumming and other problems in your injectors or carb, probably resulting in the need for a carb or infector rebuild. It is cheaper to use a good stabilizer and yes run it through the whole fuel system.
Stabilizing diesel is a good idea as well. It is cheap insurance.
Tom

[David M]

Be sure not to leave the newer fuel that contains alcohol inside the engine over the winter. Run the engine with the fuel valve closed so as to get rid of the last of it inside the engine.

At work we had an older carbureted outboard that kept fouling on the newer gasoline with alcohol. Even with fuel stabilizer meant specifically for gasoline/alcohol mixtures, it kept fouling the carb jets. The partial solution was to run all the fuel out of the engine after each use. After three expensive trips to the outboard shop to have the carburetor jets cleaned out, we gave up and replaced it with a fuel injected outboard. Problem solved.

The alcohol is a problem for many older carbureted engines and fuel stabilizer sometimes is not a solution. Its probably at least worth a try.

[denmanislander]

Thanks all - always get great info whenever I post here - Sure appreciate it! Happy winter planning for spring!!!