Ethanol E10 fuel in a 2 stroke outboard?

[joe17]

I usually use the non ethanol petrol in my outboard, but I think I just topped up my tank with 5 litres of E10. Is it a problem? I have actually used the engine a couple of times since and don't remember any differences.

My first thought is just to dilute it down with another 5 litres of non ethanol / higher octane fuel and let it be.

 

[ronsurf]

It depends how old the outboard is - ethanol can deteriorate rubber fuel lines and seals if it's not ethanol compatible. This is over a period of time though.

Another potential is for the engine to run lean - ethanol contains oxygen which can upset the fuel air ratio. Again, this would depend on the age and size of the engine. It's a problem for old two stroke bikes.

 

[sarabande]

in all our small petrol motors we add Briggs and Straton Fuel Additive.

https://www.amazon.co.uk/Briggs-Stratton-Additive-Stabiliser-992381/dp/B003374F9E


Makes a good difference to starting, and reduces the likelihood of carburettor diaphragms and fuel pipes being affected by ethanol.

Having replaced two chainsaw carburettors this year before we moved to B&S fuel stuff, I am also using a premium petrol at about 10p/litre more expensive. If that stop £60 repair bills, I am happy.

 

[joe17]

It depends how old the outboard is - ethanol can deteriorate rubber fuel lines and seals if it's not ethanol compatible. This is over a period of time though.

Another potential is for the engine to run lean - ethanol contains oxygen which can upset the fuel air ratio. Again, this would depend on the age and size of the engine. It's a problem for old two stroke bikes.

Thanks.

It's from the early 90s, so old, but not ancient.

 

[Len Ingalls]

Just use it up within 60days or so-should be ok.
Most of the problems with E gas is that the ethanol only lasts 60days & you end up with low octane fuel.
Also,ethanol causes a build up of white crud in carb if not burned soon.

 

[thinwater]

That may be old enough to be pre-ethanol materials. I am a US sailor, and we have had e10 far longer and are better adapted, but if the engine is not fitted for it, it can be real trouble. There is no additive that will make any difference.

higher octane is irrelevant. Just myth.

Regarding e10 additives, I've done a bunch of testing on US additives, but not much UK. I am working with the standards organizations on standardizing additive testing. The bottom line is that about 50% are snake oil, some of them popular brands. The best advise at this time seems to be either Soltraon (Startron in US) or OEM brands.