Sta-Bil

[Vader440]

What's your feelings on putting Sta-Bil in the gas tank before putting your sled away for the summer? Or is it best to drain all the fuel?

[Boomologist]

I've done both.
On sleds that have sat for 10 years I drained the tanks and ran the engine until all fuel ran out and it stopped. Then fog the engine. There is an argument about not draining the tank because air will replace the fuel and air contains moisture which will condensate out over time. On aircraft we kept the tanks topped off so no air would get in and sweat inside the tank. But no matter what you use after so many seasons the fuel will go bad.

On other engines such as my boat I use Sta-Bil or the equivalent and keep the tank full so no air is in it. The boat hasn't seen the water for 3 seasons and I finally got around to draining the tank this fall/winter. Ran all 45 gallons through the car and didn't notice a difference between 3 year old gas and fresh.
It all depends on how long it will set.

[Vader440]

That's good information. Thanks!

[DougKauer]

You could just start it up ever once in awhile and let run, This way the gas still gets circulated through the system. I have done this with now problems.

[mswyka]

My first thought is that it is too early to start thinking about putting the sleds away. 

We keep ours wet and start them once or twice in the off season if for no other reason to get a whiff of 2-stroke.  They have run well year over year with this approach.

[Boomologist]

Gas without alcohol has a shelf life of a couple years. If it's a gas/alcohol mix such as we get out of the pumps it starts to degrade in a few months even in a sealed container. The alcohol has a great affinity for water. in short time under the right conditions the fuel will do a "phase-sepration". The alcohol/water will settle out to the bottom of the tank and the gas will float on top of it. Your pick-up tube will be drawing alcohol/water which may be what some are seeing as poor running engines, loss of power, internal damage caused.