Ethanol is good as long as it doesn't sit unused for any length of time.
It will eat the seals in the fuel system and the non-metal fuel lines. It will corrode the fuel pump and destroy it; and it will without a doubt oxidize and corrode the metals in the engine. If you fill up every week, use an ethanol blend if you like; but Ethanol will eventually damage non-ethanol rated fuel systems and engines. Pre-1996 "GM" are not designed for Ethanol in any capacity. PERIOD! To be honest, even that is an iffy statement. In 1996 GM "tuned" the PCM from the Factory to run on 10% (or less) Ethanol without much loss in economy or power, but the fuel system and engine was NOT designed for it. It's still not recommended.
The reality is only 2004+ engines are properly tuned for Ethanol, properly designed for Ethanol, and 100% unaffected by it.
There are 2 things about Ethanol blended fuel people don't realize.
1.) It's hygroscopic. That means it ABSORBS MOISTURE. Let it sit long enough and it will suck the moisture out of the air and hold onto it. This is bad.
2.) After just a couple weeks, it starts to turn to a jelly. This is very bad for injectors. Only the the very high pressure fuel systems of modern (2004+) cars are not affected by this problem as they can force that jelly past the injector. 1996-2004, again fine, but not actually recommended as the materials of the fuel system aren't "hardened" against ethanol.
It's nasty stuff.
If you filled up the fuel tank with an ethanol blend today, ran the engine to temp, shut it down and let it sit 2 years, you're done. Injectors, fuel pump, fuel lines. All done. Do the same thing with E0 and it'll start right up. 2 weeks is really where the problems with Ethanol starts though. This is why I say if you're always filling up every week, use it. Although you are still doing damage, it will take much longer for it to show.
Here's my experience. I bought my 1993 Trans Am January 1st 2003. I ran E0 through it, all was well. Car was a beast and got between 18-24 city depending on my attitude. 18MPG was my lowest ever though. A couple years later, my pumps went to E10 and I didn't realize it. My fuel economy dropped to 13 average, 15 if I really pampered it. This drove me absolutely nuts! I average every tank as fuel economy is a good indicator of engine health. Been doing this since I started driving 36 years ago and my T/A was the first vehicle to loose MAJOR economy on me. I lost 2MPG in an engine once because the spark plugs were shot, but nearly 10MPG? ...I checked everything except a few plugs I couldn't reach. All is well? OK then... I went to a Mechanic, they checked over everything and couldn't find a problem either. Most I could get out of them was "It's running really really rich, but there's no reason for it that I can find.".
...so I dealt with the crap fuel economy. I loved my car, it was still a beast, and I kind-of agreed to myself when I bought it that if it gets 15 city I'd be happy. So, acceptable even though I obviously had a problem somewhere. 18-24 city from a V8 though was just awesome! ...and I bragged on it. Frequently.
About 18 months later, I fill my tank. Start my engine to leave, and smell raw fuel. I open the hood right there at the pump, and I see fuel shooting from my fuel line directly onto my exhaust manifold. ...fuel line sprung a leak? odd... Pull fire extinguisher from rear seat, get it ready, drove the few blocks home and parked it. I tried finding fuel lines. Not sold locally, not sold online, junkyard says it's a liability for the same reasons I need to replace mine and they will not sell either. Didn't know about Hawks Motorsports back then and they never turned up in a search. ...local mechanics won't touch it. What to do? There is a "Fuel Line Kit" on the internet for $600 I can use to make new fuel lines, but I literally only need 6 feet of the hundred or more on the spool. Seems like a waste of money. What to do? Well, cut-n-splice! So I did. 2 months later, the other line sprung a leak. About 9 months after that, another leak on the original line.
I questioned why this was happening and I did my homework. Ethanol could cause this? ...and impact my fuel economy that badly too? Really?
Found an E0 pump in the next county and started using it. Not a single fuel leak since, and get this, right back up to a minimum of 18MPG instead of a maximum of 15! ...over a quarter-million miles on my fuel pump at this point too. Even after sitting for over 2 years without being ran, I charged the battery and the engine fired before the key was fully turned. I would bet my life that if Ethanol was in that tank last I would have needed a new fuel pump at a minimum. Very few pre-2004 fuel pumps that sit submerged in ethanol without use survive 18 months, none make it past 2 years. Ever.
Again, NASTY STUFF!
On the small gas engine front, I had a Suzuki DRZ400SM. Awesome little Thumper. That bike could not sit for a full week with E10 in the tank without the carb gumming up. I literally had to clean the carb every time I wanted to ride. Switched to E0 there, bike could sit 6 months and fire right up. There was also a time or two (or six or eight) before E0 that the float stuck and the carb emptied the fuel tank onto the floor overnight. My brand new $800 push-mower? 2nd season I forgot to winterize it. It only sat 6 months. Wouldn't start. Went to clean the carb and the float bowl literally disintegrated in my hand. The stand-offs the jets are screwed into? Yup... Gone! A white powder was all that was left of them. Couldn't afford a new carb, couldn't locate a suitable used replacement, so I bought the no-frills $150 push-mower. ...it has a plastic carburetor, and it can accept up to E15. Only run E0 in it now, and no problems, obviously. It's designed for Ethanol though and that's what's important.
My mini-bike is not ethanol rated, all the damage from ethanol was done in the first six months as well. Went to E0, and it has been fine for YEARS now. Never had to clean the carb even once after E0 switch, and it sits for 6 months to a year every time. Always starts 1st or 2nd pull. I shut off the gas when we come in and run it dry. My sons go-kart on the other hand, is ethanol rated and does not have a fuel shut-off. Even though we run E0 in it, we do have to clean the carb one or two times a year because it gums up a little. Even E0 shouldn't sit really...
E10, Nasty Stuff!
YES! There are those who say "no problems" with old cars. BULLSHIT!!! Flat out bullshit. NOTHING that was not explicitly engineered for ethanol will last with E10 going through it on a regular basis. ...and it certainly can't sit for extended periods of time without damaging the systems either. You can NOT see your fuel pump, you can NOT see the internals of the fuel lines, you can NOT see the internals of the engine, you can NOT see the the spray pattern of your fuel injectors. You do NOT know what damage is being done until it makes itself seen. Right?
Let's pretend for a moment that NO physical damage occurs in a non-ethanol rated fuel system running E10. Fact is, until 1996 when GM tuned the PCM for ethanol, running a 10% ethanol blend resulted in 30% lost fuel economy. Get that? 10% less gasoline and a 30% reduction in fuel economy. THIRTY PERCENT! ...do the math and the more expensive E0 saves you money at a minimum. Period.
Indulge a little conspiracy theory for a moment. Adding 10% ethanol to gasoline reduces fuel economy 30%. FACT. That means 30% more fuel is actually used to travel the same distance. This isn't beneficial to the environment, and it isn't beneficial to your finances. So where is the benefit? PROFITS!!! It was G.W. Bush who as President mandated E10. "Renewable Fuels Standard" my butt. Dinosaurs aren't renewable. ...those profits though! Renewed every time you fill up. Remind me what industry the Bush family is in again? No conflict of interest there. Nope! not one bit...
I gladly pay the premium for E0. I run it in everything I own, even in my '96 Corvette that is "tuned" from the factory for E10. In my vehicles I don't have to worry about the fuel system, and my small gas engines are happier for it. As am I. I don't mind the occasional carb clean, but literally every time I want to use the machine? That gets very old really fast. Ethanol has less energy to give than straight gasoline. E10 is 15-30% less powerful than gasoline, and E85 is up to 35% less powerful than E10.
Nasty Stuff...
...have I said how nasty ethanol blended fuels are?
Everyone is free to do as they wish. I have had very bad experience with E10. 6HP, 40HP, 400HP. Small, medium, and large engines. All pre-2004, all affected by E10 in some way. Maybe that is because I'm in Florida and the heat and high humidity affect E10 more adversely? Fact is though, my nightmares with fuel lines and carburetors stopped literally the same night my usage of E10 did. Maybe I did 2 years on Ethanol before I saw issues, and maybe it wasn't the ethanol eating my fuel lines; but I'm of the mind that if it wasn't the ethanol doing what I was told it could do, why did I stop springing fuel leaks when I stopped using ethanol? Over 10 years since the last "leak". Even if you call it a coincidence, there's still proof that it corrodes the metals used in the construction of our old engines.
Just because you can't see the damage does not mean it doesn't happen or isn't happening. Best to err on the side of caution, run only E0, and consider religious attendance at a station that sells E0 as the one of the prices of driving a Classic car. If that price is too high, you're in the wrong car.
...otherwise? Welcome to the club!
Now, E0 is hard to come by at the pump for some folks, but even today, more E0 pumps are appearing than disappearing. If there are truly no E0 pumps at local gas stations, then there are no E0 fill-ups for you. Not your fault, but E10 still isn't your only option. You should still find an E0 pump at a Marina, because 90% of boat engines don't do Ethanol. Marina pricing is very cost prohibitive though, and again, the high price is the cost of ownership. Not OK with it, maybe get a smaller boat or give up boating, right?
Maybe there aren't any Marinas around? There is another way. You can get "pure gasoline" from E10, E15, and even E85. It'll take a little time, minimal effort, and a small one-time investment in materials. The process is wasteful, equal to the percentage of the ethanol, and it can be dangerous if proper safety procedures aren't followed. You can die, you can burn your house down, blow up your dog, wife, children, etc. Try this at home, but don't ever say I said to do it: Buy E10, let it settle, skim off the ethanol. That's it... All done. ...and you're left with pure gasoline.
Ethanol actually does not blend with gasoline. Just like water, it settles into it's own distinct layer after a length of time and can be removed. The 10% loss in volume due to the removal of the ethanol is probably made up for with the cheaper cost of ethanol. It might even balance out financially. I never did the math here. Way back when, the closest E0 pump to me not at a Marina was 21 miles from home. I used only it. Then I moved a mile from it. Then I moved 6 miles from it. Until last year when a closer E0 pump came online, I attended that pump more religiously than a Muslim prays.
One time I bought a tank of E0 from a small Pakistani owned station here in town. You could smell how old that fuel was. Literally smelled like 100 year old farm equipment, and was so orange it was nearing brown. More varnish than gasoline really. Very bad fuel to say the least. ...still preferred to E10 in my eyes. Sure, I never went back to that pump, but I didn't leave that pump for a fresh batch of E10 after pumping a gallon either.
I guess it's that whole "Once bitten, twice shy" thing. I've been bitten by E10 too many times. I'm very shy of it. It's evil in my eyes. I won't use the stuff even in engines explicitly designed for it. I know those engines do not benefit even the slightest from E0 and I'm simply wasting my money there, but still, E0 can't hurt. Ever. E10? ...not so much.
...and just wait. It's not going to be long before E15 is mandated. Pre-2004 vehicles can NOT use that stuff. Even for a minute. It'll do the same damage in months that E10 will in a decade. I think this was discovered in Brazil or some other South American country that uses primarily a 15% blend of ethanol. Tore their vehicles up real bad, real quick. The metals used in our old cars can't stand up to the corrosion cause by ethanol. The more ethanol, the worse it is, and "worse" seems to be an exponential problem. Up to 10% ethanol, results vary over time. Just 5% more, and results are very conclusive, very fast.
Me? I say don't. Just don't. You've got a Classic Car. Find an E0 pump and use it with pride!
