[Putershark]

Chevron states that in "Ideal" conditions that fuel can be stored for up to one year...

http://www.chevron.com/products/prod...term_gasoline/

I though have seen fuel (mostly your Diesel grades) start to break down in as little 45 days. The above link though does have some good tips for long term storage with the best option (of course) to use it up as fast as possible. Now I do not see Octane degradation being much of an issue since most Outboards are "designed" to run on 87 octane fuel. Here again, that ECU programming to run on 87 grade fuel was done when the engine was as clean (zero to low carbon build up) which in many times is NOT real world conditions at all.