Ethanol vs premium

[shoestringmariner]

I have been reading about the woes ethanol can bring, but also too that low octane is better for small engines. I am having trouble finding fuel that is ethanol free, that isn’t premium.

So which should I run??

[outboard315]

Premium, since you will have more of a mess if you go ethanol.

[frankr]

What was the reason they gave for low octane being better that premium? I know of no rational for that. In fact premium MIGHT be better in a very few motors that could be subject to engine destroying pre-ignition. But the general rule is there is no advantage or disadvantage to using premium. Except premium is a waste of money if not needed.

[jerry-ahrens]

I don’t think you need premium [high octane] fuel particularly, just 87 or 88 octane is fine. Here in Missouri. all ethanol free fuel is called ”premium” because is is usually 91 octane. The other pump gas is 87 octane. Maybe that is the question you are asking?

[shoestringmariner]

I had read that premium was a slower burn and that it could lead to more carbon buildup and lead to harder starting.

It seems that around here, only the 91 octane contains no ethanol. I thought Shell fuels were all non-ethanol, but I have since read that that is not the case due to the fact there are only 4 refineries in Canada, so all unleaded and mid grade contain up to 10% ethanol. I dont know if that is accurate or not, but I’ve noticed not all stations list on their pumps whether ethanol is present or not, so I suspect it is present.

For me its not about cost, its about performance and longevity. I assume premium is the lesser evil?

[outboard315]

Typically 87 and 89 octane have ethanol and 91 or 93 is ethanol free. The only down side to running higher octane then needed is you would get slightly better gas mileage running lower octane since the lower octane is easier to burn. But I don’t recommend running ethanol in anything that you don’t use daily. Once ethanol sits it starts gumming up everything and eating certain rubber fuel hose.

[fisherman6]

The only ethanol free fuel in my area is sold as recreational gasoline and is typically 90 octane "premium ". The regular midgrade and premium automotive gasoline all contains ‘up to’ 10% ethanol. I have actually heard it usually runs closer to 15% most of the time. The rec gas sells for about $4 a gallon and rarely fluctuates with auto fuel prices unless they get very high. They just make elevated profits on it. I still buy it to run in all my small engines and outboards though. The ethanol is really bad for them and has caused lots of problems for me before I switched. I switched as soon as it became available to me. MUCH better! Definitely opt for ethanol free fuel, premium or not.
-Ben

OldJohnnyRude on YouTube

[bluehaze]

This is an interesting site. It explains different aspects of fuel. Click on the articles about Octane, specific gravity, and ethanol. Interesting reading, and not just hearsay. 😎

http://www.racegas.com/article/index/tags/Tech

[chris-p]

Scott,

For us if you want non ethanol, buy at the marinas around us. I just buy 87 octane though from the pump for all of my motors.

I have a gazillion motors, and if you have a modern carb kit in, changed fuel lines, etc…., this fuel is not a problem. I have had quite a few guys bring me in motors to repair, that they blamed the ethanol gas on. The real problem was their gummed up carbs, that hadn’t been cleaned in decades. The ethanol cleans, frees up debris, etc… So yes it will gum up a carb, but not a clean one. Not that I have seen anyways. That being said though, I would not leave fuel in a carb for long term storage, ethanol or not. Run stabilizer on your last outing, and you will be fine.

[PugetSoundBoater]

Google pure gas .org.for a list of Ethanol free locations stations and marinas in US and Canada by state and province. Shows which octane and brand the location sells.

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson

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