Does Fuel Degrade Over Time?

[rmay635703]

Gasoline does slowly degrade but the trouble isn't with the gas itself, its what the gas does to components it touches while it sits.

The best example is when the gas isn't in a perfectly sealed container, portions of the gas slowly evaporate and others slowly degrade as the substances holding them in solution go away. The end result is a tough varnish.

Your carb usually isn't air tight and gets varnished rapidly when you leave a motor sit with old gas. As the gas ages it leaves more varnish after it evaporates, clogging your carb.

Even when gas is in a well sealed container it tends to varnish the surfaces it touches when it sits, just more slowly.

So the issue isn't with your old gas, it would be with you not running your engine for a period of a month or more often.

Cheers
Ryan

[Meph]

I guess my issue is that I have no baffling in the fuel cell so the more I drain it the more likely it is to starve the engine when decelerating, but I only run 91 ethanol free gas so it sounds like i have more time to play with it

[euromodder]

Originally Posted by Niner

That said, if I were using fuel, I'd try to drain the tank as much as possible.

The only advice I've ever read is to fill the tank as much as possible, to limit the extent of the evaporation (and reduce tank corrosion).

[rbrowning]

Yes the gas degrades with time. That is why I fill my 17 gallon tank after every 494 miles whether it needs it or not!

Or more often if my wife drives it and I don't feel like pushing!