gas/ oil mix.

I have finally found the correct gas/ oil mixture for my old Evinrude, but now I have another perplexing question. Having first hand knowledge of what ethanol tainted gas does to an engine, should I try to find regular gas without the dastardly agent, or use premium gas and go a little heavier on the oil? I going to have to buy a new gas tank as it is, and I was just wondering if the higher octane would harm my motor.There was a station in my area that used to carry reg. without ethanol, but I don't know if it's still open or if there are any others. I am deferring my concerns to you folks, who may have already had this issue and can help me out.

i would do my best to find pure gas. check this website out:
https://www.pure-gas.org/

The way I understand it you want De-Oxygenated Gas. Period. Anything else will just gum up the mix. However I would wait for guys with much more experience to weigh in.

lovedr79 said:

i would do my best to find pure gas. check this website out:
https://www.pure-gas.org/

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Thank you for the link sir. I looked it up and was extremely surprised to find out how many places close to me carried pure gas. I am forever indebted to you. Now to get a new tank and try it out......after some new spark plugs and a way to get a barrel of water to set it in. Again, many thanks to you.

AnglerC said:

The way I understand it you want De-Oxygenated Gas. Period. Anything else will just gum up the mix. However I would wait for guys with much more experience to weigh in.

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Thank you for your answer. I have one from a member who gave me a grand tip that may fix my problem. I do appreciate all the input.

My Mercury Optimax says to use minimum 87 octane fuel. Would it be better to use fuel without ethanol?

birdsnest4ever said:

lovedr79 said:

i would do my best to find pure gas. check this website out:
https://www.pure-gas.org/

Click to expand...

Thank you for the link sir. I looked it up and was extremely surprised to find out how many places close to me carried pure gas. I am forever indebted to you. Now to get a new tank and try it out......after some new spark plugs and a way to get a barrel of water to set it in. Again, many thanks to you.

Click to expand...

there are more out there than most think. i have several that i didnt even know about in my new neighborhood.

My manual specifically says in relation to fuel the following:

Preferred Fuel: Any regular unleaded, regular leaded, or premium unleaded gasoline having the recommended octane rating, and not extended with alcohol.

Acceptable Fuel: Any of the above gasolines with up to the following percentage alcohol by volume: • 10% ETHANOL or • 5% METHANOL with 5% cosolvents.

My motor is a 1994 Johnson. Not sure how long alcohol extended fuels have been around, but it looks like it's something that outboard manufacturers at least had in mind and accounted for when building their engines at least back as far as 1994.

BUT, my manual also says the following about alcohol extended fuels:

OMC products have been designed to operate using the Preferred Fuel or Acceptable Fuel; however, be aware of the following: • The boat's fuel system may be different regarding use of alcohol fuels. Refer to boat owner's manual. • Alcohol attracts and holds moisture which may cause corrosion of metallic parts of the fuel system. • Alcohol extended fuels can cause engine performance problems. • All parts of the fuel system should be inspected frequently and replaced if signs of deterioration or fuel leakage are found. Inspect at least annually.

I don't have the luxury of any alcohol free gas available in my area. So I use premium gas with the appropriate amount of Stabil in my tank and haven't had any issues thus far.

As far as higher octane fuels, my manual goes on to say this:

The use of premium grade fuels is specifically encouraged. Most national brand premium fuels ~ contain detergent and dispersant ingredients advertised to reduce intake valve and fuel injector deposits. These ingredients also remove and prevent carbon buildup on pistons and rings. These ingredients can extend engine life while maintaining a high level of performance.

Now all of this is obviously coming from the manual for MY specific motor and model year. I'd encourage everyone to read up on what THEIR engines manual recommends and make the best decision based on the manual regarding fuel grade and alcohol extended gas.

When getting the new gas tank, might spend some more to get new fuel lines from the tank to the motor that are rated for ethanol just in case you find yourself using ethanol.