Modern Ethanol Gas will do that to the old rubber O-Rings.
I should say rubber O-Rings they don't have to be old, some NEW kits still supply rubber O-Rings.
The Neoprene ones are more resistant but that is all, resistant is not Ethanol proof
Use the Honda Gasket set and then either purchase fuel without ethanol or the lowest amount available. I also use a couple of ounces of the synthetic 2 stroke oil in a tank of fuel. Works as a stabilizer and mitigates the ethanol.
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