Fired up the generator today, and sure enough, noticed that there's a small leak in the water separator cup on the fuel line. Pulled it open, the O-ring is utterly degraded. Fortunately I happened to have a replacement, but then I started thinking unhappy thoughts about all of the other stuff that must be feeling the pain of 10% Ethanol.

I found some information in a number of places that says,

"The phase-separated [Gas/Ethanol] solution contains much more ethanol than E-10 fuel — perhaps as much as 40 to 60 percent or more, and that causes fuel hoses to soften, rot or delaminate. With elevated ethanol levels, gaskets tend to swell, blocking off small holes or passageways. O-rings start to distort and leak. The real damage occurs as an engine sits unused for days or weeks with the highly concentrated water/ethanol mix eating away the insides of the fuel components."

Like in a generator or in a boat.
Now recently made equipment (2006 or later) has "rubber" that is stabilized, but my generator was made in 1998, and it's certainly NOT going to have stable rubber components.

I really, truly did NOT want to do a strip-down and rebuild of the generator (and I'm really kicking myself for not just going with propane) but I think it's better safe than sorry, so next weekend, I'm replacing ALL rubber and gaskets on the thing...a chore I did not want AT ALL.

Oy.