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good01

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The fuel dock where I buy fuel from now has non ethanol fuel. But the guy at the dock says its bad to mix with ethanol fuel. Can you mix these without any issues. I would stay with the non ethanol fuel. Thanks in advance.
 
There is no issue mixing, as long as the octane rating of each meets the requirement of the engine. Most ethanol fuel has a rating of 87, (which is what the vast majority or car engines require), 5% ethanol is usually 89 raring, & no octane makes for 91.
if your engine manual says 87 is required, mix them all you want, as long as you use the fuel before any ethanol can absorb water & phase separate.
I don’t know what engine you have, or it’s age. Older engines can have issues with ethanol fuel, not because the engine itself doesn’t like it, (ethanol is very resistant to knock), but because legacy fuel lines, carb & engine seals can degrade. Alcohols are very good solvents, & are very efficient at keeping internals clean, but they can play havoc with seals not designed to be impervious to alcohol.
 
It is a 2001 Johnson 225hp. It does say in the manual 87 octane is what this engine would use. In Maryland we have never had this choice unless you went to a small airport to get your fuel.
 
Good info. We have covered ethanol quite well here over the years. The other problem that we know with ethanol that as it separates, some of the "octane" gets trapped with the "sludge" which has been created by the ethanol/water mix.....that will settle to the bottom of the tank. The "sludge", which is described as "phase separation", will carry or suspend the water. This mixture is destructive if introduced to your motor. Why? It is corrosive, as well as carrying much of what was supposed to be your octane. Alternatively, if the fuel pickup grabs the main petrol fuel which is lighter....and floats on top of the "sludge", the fuel will have very low octane....also resulting in engine/motor damage. Once this happens, you will wish that ethanol was never added to our fuel. The situation is worsened when fuel is subjected to moist environments.....yes.....like marine, aviation, and humid areas. For this reason, airplanes are not allowed to use any ethanol in their fuel. Also many marine motor/engine manufacturers recommend a max of 10 percent ethanol....and use up the fuel within 3 to 6 months.
 
So timguy you also agree it would be best or ok to switch. I have ran race cars with methanol but we also always ran gas through the engine at the end of the night. I worked hard over the winter to get this engine running really well and it seems to have paid off just dont want to hurt anything.
 
Methanol is a different beast than ethanol. Decades ago, I operated Rolls Royce engines that used methanol & water injection to boost power. Water cooled the air charge, allowing a denser mixture,(more power), methanol allowed the entire mixture to burn. Methanol is a virulent poison, doesn’t have to be a orally ingested, it will penetrate skin.
You are confusing the 80/87 octane aviation fuel with “car gas” 87 octane. The aviation fuel (coloured red), is formulated different, as it has to resist foaming & static buildup in turbulence, & gassing when exposed to lessened atmospheric pressure at altitude. The “regular” fuel you buy at your local gas station is 87 octane, & is fine in your engine, that is what the manual states.THERE IS NO ADVANTAGE, OR POWER GAINED BY PURCHASING 91 octane,(hi-test). By 2001 fuel lines, pumps etc were built to use normal car gas. It will not hurt anything, with one caveat.
As Timguy mentioned, the ethanol will absorb water, & phase separate. All gasoline loses reed vapour Pressures with time. Higher octane fuels can lose some of this, & still run fine, whereas the lower octane (87), may experience detonation once it deteriorates.
This, along with phase separation is not an issue IF you use your boat on a regular basis & the fuel never gets old. IIRC the refineries give it about a 6 month shelf life, but in a marine environment, where it may be exposed to more moisture, i make sure I use it within a month.
Many deride using fuels with ethanol, & that is certainly valid with fuel that may sit for months, or used in older motors. However, there are some very good benefits of alcohol. It is a very good solvent & will keep injectors & carbs very clean. (Look at cars with 400,000km without ever changing an injector), It does not build the varnish to the degree old school formations did.
In short, if you only burn a few hundred litres/year, the extra cost of ethanol free doesn’t amount to much. If your boat sits for weeks at a time, ditto, use ethanol free.
If you are going on a long trip, & plan to fuel several times over a short period, there is nothing wrong with saving $$, & using regular gas.
 
Excellent. You talk about "winter"....you live in a seasonal area that will not let you run your boat for months at a time. I certainly would avoid ethanol. There are other additives that you can use to safely keep your operations clean. Ethanol is a "double edged sword". Besides that.....it produces less power, not significant, but about 2 to 3 percent on E10. Secondly, it is hard on anything with rubber/latex composition.....as well as many polymers implemented in our equipment.
 
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Well the boat I fish in the Bay with it gets hauled out the last of December and put back the first of March. I am out of the water about 3 months and my smaller boat I use unless the river is frozen over. And I use the bigger boat all summer about 3 times a week. I was just glad to see they started carrying that type of fuel. Again thank you for the responses.
 
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