Gasoline / Ethanol

[catchersrock]

Can someone please give me an education on Gasoline, Octane, and, Ethanol? I have been buying ethanol free gasoline from a small, local, non branded station for my 2 stroke outboard. The Octane rating for this ethanol free gasoline is not posted on the pump. It is comparatively expensive. It is more than premium gas. Would I be better off to buy premium from a branded station? I did notice that at a local BP, they have ethanol free at 89 octane. Would that be better for my motor than premium gas? Maybe premium gas with an additive? Assuming price of the gas and additives is not a consideration, what will give me the best performance and the best protection for my motor and fuel system?

Thanks,

[985crabs]

Catcher,

You've got a brand new motor so it may have been re-engineered with materials that are not susceptible to the deteriorating effects of ethanol. However, I think the best bet, for anyone who can find it, is ethanol free fuel at 87 octane or better. I don't know that the higher octane fuels or additive-laden fuels will protect you from your motor dissolving from the inside out if it wasn't built to handle it.

[freezerfiller]

It's not so much your motor, but the wet environment that boats typically like to be in, and the length of time that the fuel sits unused. Ethanol likes water and can absorb it even from the air. when it gets saturated, it separates from the gas into it's own layer, Since ethanol is very high octane, the remaining fuel is much lower octane than it was when the ethanol was in it. So, unless you run your tank empty every month or two, ethanol free is the safest way to go. that ethanol free 89 from the bp is fine and better than the 87 or 89 ethanol versions. Ethanol is also hard on older fuel lines that weren't designed for it.

[Juan]

ethanol is evil and it doesn't burn as well as non ethanol fuel so along with all the other issues ethanol causes, your fuel efficiency won't be as good. I agree with crabs and freezer... use an 87 or 89 octane non ethanol. There have been several studies published lately that say buying higher octane fuel is wasting your money since it has no advantages over lower octane fuels when used in cars... I would guess the same thing applies to marine engines.

[yessnoo]

It is such a shame that non ethanol fuel is so expensive now....not because it is more expensive to make...but because the demand is so high after the government mandated against it. And it is about to go up to 15% ethanol.

Anyways would be interesting if people share where they get no ethanol fuel....in Texas it requires driving an extreme distance unless I just don't know the good spots

[freezerfiller]

go to www.pure-gas.org or get the pure gas app!

[mosquito13]

You got a shop you will have your engine serviced right? Ask the person who will be working on it what kind to purchase. Bet they tell you rec gas, mine did.

[Warpig]

I've used 89 octane ethanol free gas for as long as I've had a boat on Lake Erie. It avoids the phase separation issue. I was always worried about this since the boat is in the dock in a high moisture environment and I store it for the winter for 6 months. Plus the Verado I had on there would run on 87 but the manual always said it would run "better" on higher octane fuel. With running the ethanol free fuel and adding fuel stabilizer (I generally use Startron)every fill up, I never had an issue.

I was an engineer at GM for a while and the Powertrain guys never liked the effects of ethanol. I've always tried to avoid it where possible in the boat.

[Simple Man]

Oct 19, 2018 8:03:33 GMT -6 985crabs said:

Catcher,

You've got a brand new motor so it may have been re-engineered with materials that are not susceptible to the deteriorating effects of ethanol. However, I think the best bet, for anyone who can find it, is ethanol free fuel at 87 octane or better. I don't know that the higher octane fuels or additive-laden fuels will protect you from your motor dissolving from the inside out if it wasn't built to handle it.

Even if it is alcohol resistant it is not alcohol proof. The ethanol will eat it up too just take a little longer.

[tigerhead]

in Texas it requires driving an extreme distance unless I just don't know the good spots

I don't know where you are in Texas, but the pure-gas.org website will tell you if any non ethanol fuel is sold near you.  I'm in the Houston area and the nearest non ethanol to me is sold at a Buc-ee's in Clute. 

The non-ethanol gas situation here is a little confusing. There are a few places that sell non ethanol that they call "racing fuel".  It's very high priced and I'm not exactly sure how they are getting around the EPA rules.  The cost would kill me in my boat.

The non ethanol that Buc-ee's sells is not alcohol free, but it is ethanol free.  To get around the EPA they blend it with isobutanol.  From what I've read, isobutanol is an alcohol, but it is not hygroscopic, which means it will not absorb water from the atmosphere.  It is also suppose to be non harmful to fuel lines.  It produces more BTUs than ethanol fuels, so you get better engine performance.  I usually try to stay topped off with ethanol free regular gas I buy in Louisiana. I actually fish there more than I do in Texas.  But my next fill up will be at the Buc-ee's in Clute. 

[yessnoo]

Good info tigerhead.

Ya I heard that the bucees in katy on i10 sells it also....problem is I live in la porte on the east side. Not sure I am willing to drive 2 hours or more round trip to fill up the boat. My only other real option besides the race fuel thing like you were saying is the galveston yacht basin....unfortunately again unless I am going to Galveston to fish it is around a 2 hour round trip...guess I will just stick to ethanol

We just had to pump one of my coworkers boat fuel tank due to all of the water in it....can't find any leaks so gotta figure between him storing it on the water and running ethanol fuel it must have added up....His motor wouldn't run on it until we pumped the fuel tank and put fresh fuel in.

[tigerhead]

Yessnoo,

Looks like a no-go on Buc-ee's for me too.  I'm right next to you in Deer Park and so it would be a long drive for me also. I would still do it to avoid the ethanol, but I checked the price and they want $3.80 a gallon. That price, along with the long drive is just too much to justify.  I'm headed for Lake Calcasieu in 10 days and I will probably wait till I get to Louisiana to fill up.  I just pumped my tank out in order to do a calibration on a Garmin GFS-10 fuel flow sensor I just installed.  I can buy non ethanol in Lake Charles for $2.69 a gallon. Makes a lot more sense.

[Juan]

Practically every store within a 100 miles of here stocked up on 5 gallon plastic gas cans during hurricane Michael and they have a zillion they didn't sell. I'd buy a dozen or so and fill up with non ethanol when I had the chance. I have 10 and I only have to drive 15 miles to the nearest non ethanol station.

[freezerfiller]

FYI, "racing" fuel is exempt from the ethanol requirement, much like "racing" fuel cans are not required to have the new triple safety check valves and things that make them pour slow and hard to open.

[yessnoo]

Good info freezerfiller. I haven't called yet and got pricing from gyb or youngs fuel yet...but both are pretty far out of the way. I think I could drive the boat to GYB from la porte faster on a smooth day than driving it in the car lol....at least then i wouldn't have to transport the fuel...i could just burn it all up returning to la porte lol.

Honestly I haven't yet had a direct issue from the ethanol...and hopefully it stays that way. I try to use my boat at least twice a month so maybe that helps?

tigerhead we should meet up sometime and compare boats or go fishing or something