I was chatting with a marina mech last year abt this subject. He said the older outboards were giving the most trouble. The insides of the old type fuel hoses were turning into jelly and clogging up the tiny carb circuits.

Make sure you have USCG approved SAEJ1527 hoses. They are resistant to alcohol.

I replaced all my fuel hoses last year. When I asked if the hoses they sell were OK with ethanol, every vendor said that they only sell the newer USCG approved stuff.

As prev mentioned, phase separation is the other killer. If the ethanol laced fuel sits too long (8 weeks or more) and is exposed to moisture (like boats are via the fuel venting sys) the ethanol will bind with water then fall to the bottom of the tank where the fuel pick-up is located. The fuel remaining will have an octane rating in the low 80's.

Out here in CA we can't get non-ethanol fuel at the docks. Many of the fuel distributors use ValvTect to prevent the problems associated with ethanol blended fuels, including phase separation and destabilization. We don't have a choice...

I use it in everything. I can't count the number of combustion engines I have ethanol fuel in right now including supercharged (mildly 8 psi) NEVER had a problem. My S/C Mustang sits from Nov 1 to Mid April no problem. Everything else from lawnmowers to Honda engines snowmobiles 4 wheelers 6 wheelers water pumps cars work trucks ect ect all fine sitting outside weeks months at a time tanks vented no problem. JMHO I think the whole thing is over worried about. Oh yea boat also. Just had a hell of a weekend on the reservoir after boat sat from Nov 1 to last weekend when I fired it up on the hose to change fluids. Fired within two revs idled and ran fine.

Disclaimer: I'm no chemist. Just real world experience.

The grass is now 12 inches tall in my yard as I can't get my cheap little lawnmower to start. I'm not sure it will ever start again. If you listen closely, you can hear the grumblings when you use ethanol laced gas. If you have a fiberglass tank, expect to see particles dissolved and being thrown through your fuel systems.

BS. If you cant get your lawnmower started.............. well. You got more problems than ethanol.

No, what you have is a great REASON to buy a new lawnmower! Bigger, more HP, maybe something you can ride...

I had my holley carb nearly destroyed by ethanol blended fuel. Ate the crap out I the metering plates and float bowls.

Ethanol associated problems are very real! If you have not had problems yet, give it time, you will.

Ethanol is a much greater problem in high humidity states. As others have posted, ethanol will attract water in your fuel tanks and that will cause all kind of problems. Fuel filters can clog with both white and or black gel residue. I ruined an expensive fuel pump because it was clogged up with those residues. I finally got my fuel tanks clean after a dozen of clogged fuel filters, hundreds of gallons of non ethanol fuel burned and several trips back to the ramp on a tow rope.

Ethanol works fine in my flex fuel trucks and E-85 even adds a noticeable boost in power. You just burn 30% more of the E-85.

This could be Why I have not had ANY problems with ethanol fuel. Our relative humidity up here is rarely more than 10 %. But as far as the other post about giving it time I have been burning it since the beginning 20 or 30 years so I think that's long enough to show that for some reason it works for me.

My very limited use chainsaw runs on only race gas as I hardly ever use it and it sits all year. I switched to this after having ethanol problems.