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Ethanol..... again. Useful tips here.

DO NOT USE !00 octane! It's made for Nascar and race boats, not something that will run on 87 octane. Will do more harm than good.
 
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The only 87 I can get has ethanol in it .
 
Ok....guess I was wrong about higher octane burning hotter....it's actually the exact opposite:


Race gas is for race cars, period! Street cars usually have static compression ratios of between 8:1 and upwards of 11:1, and usually in the 9:1 and 10:1 area on most performance "street" engines. The problem running race gas is that if you don't have the compression to compress the fuel and air enough, you'll actually run SLOWER! I see this happen all of the time at the race track where during the Wednesday night drags, people with bone stock cars will go fuel-up with 110 or 114 octane race gas and wonder why they aren't running as quick, or as fast, as usual.


Contrary to popular belief, the more octane in gas, the COOLER and SLOWER the burn is, and more importantly, the more compression is required to get that fuel to release its energy. What happens to regular gas if you have too much compression or too much timing? You ping (detonate). How do you remedy that? You use fuel with a higher octane rating to get that uncontrolled burn back under control.


When gas becomes unstable in a burn, it goes from a "push" on the piston top, to a slam, like hitting it with a sledge hammer! Go push a car 10 feet. It isn't that hard if you just lean into it and give it a steady but sure push. Now stand behind it and hit it with a sledge hammer. You hit it really hard. MUCH harder than you could with your hand, but did it move? Nope, but you sure as hell just destroyed the trunk! That is the difference between a controlled "push" and an out of control "slam" or "detonation". It breaks pistons, blows head gaskets, cracks rings, hammers bearings, stipples the piston top and combustion chamber surfaces, and a few other undesirable things as well. To keep higher compression race engines under control, a higher octane fuel is used to keep that "push" from becoming an out of control "slam". Without the higher compression, race fuel doesn't burn real well. Alcohol is no different. If you light a teaspoon full of gas, it flashes up into a pretty big, bright flame. If you do the same with alcohol, it barely lights, has a clear / bluish flame and doesn't throw much heat. It takes more alcohol "volume" to make power in an engine to the tune of about 2.7 times the liquid volume over gas, but with that 2.7 times more fluid, it brings more power with it than gas does when compressed, and alcohol, much like race gas, likes higher compression ratios to release that energy. Typically, alcohol engines start at about 12:1 compression and go up from there to upwards of 16:1. Do that with pump gas and it will knock itself apart, literally.


I guess a good analogy would be how people refer to "jet fuel" as if it is somehow super hot and volatile, almost explosive, when in fact, all jet fuel is is Kerosene. Do you consider Kerosene a scary fuel? hell, we used to use it in camp lanterns and stoves and you'd pump pressure into the tank with a little hand pump. They called it "white gas". Not so scary sound now is it? High octane race fuel is sort of the same way. Nitro won't even burn unless it's compressed. You can literally put a match out in it, but under compression, it's a whole other story!


So, the moral of the story is; unless you have at least 12:1 compression (of more), do not run any 110 octane or higher race gas in it or you'll go slower. If you have 10:1 - 11:1, you can run up to about 100 octane and be fine, but if you have in the 9:1 area, don't even bother.
 
I just checked 6 different websites and every one of them said the same thing....that higher Octane will NOT hurt your engine...it's just a waste of money and might even get WORSE fuel mileage.
 
Now I have an interesting question . Other than the cost ,am I better off burning 90 octane no ethanol or 87 with ethanol ?


My thought would be the 90 no ethanol .
 
I agree with the worse mileage
 
Honestly as long as you add the marine stabil or Mercury additive (or similar) to protect against the ethanol you're fine with the 87.
 
Even with the ethanol free ,I use the Quickare and Quickleen . You never know what may have been or is, in the tank .


For 60-75 cents a gallon I'll stick with the Ethanol free. 
 
Well I suppose I don't blame you for doing that Jack with being up north but if you can find a gas station that pumps a lot of gas you don't need to worry about that.
 
They way they gouge us ,I just dont trust them .No reason for us to be paying 30-40 cents a gallon more than downstate .There is a fuel depot on Lake Huron less that 25 miles away .
 
I just remembered ,when it was announced in the local paper ,that they were going to open a Meijer up here .The spokesman from Meijer was asked if they were going to sell gas for less than the local stations. They said it would be the same price as downstate . That lasted about a week ,
 
My understanding of the ethanol debate is:if you have been running ethanol free fuel in your boat for a long time. You should keep running ethanol free gas,because the ethanol will react to the gum deposits that ethanol free fuel creates with in the fuel system. It just so happens that I run regular with ethanol in my E-tech. Evinrude  just states that all fuel should be treated with a ethanol treatment .I've never noticed any performance issues, therefore I 'm planning on using the regular with ethanol. Just my 2 cents.
 
A friend of mine runs ethanol ( dont know if he treated ) just paid $650.00 to have his carbs  rebuilt 
 
Jack M said:
A friend of mine runs ethanol ( dont know if he treated ) just paid $650.00 to have his carbs  rebuilt 
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As I said,if the boat was run on ethanol free fuel previously.The ethanol will release the gum and plug up filters and carbs.My E-tech has fuel infection and never seen non ethanol fuel.
 
Mine never has and never will .
 
I just ordered two 5 gallon cans of non-ethanol fuel through my hardware store supplier and plan on diluting the E-10 in my Yamaha, and my Honda 5hp on my dingy.  $55 per can.  (actually 4.5 gallons)  No other options nearby me here in Mass.  Both boats barely go thru a tank per season, so the shelf life of non-ethanol is important.  Especially when sitting over the winter in the barn....  Plan on running the non ethanol in my snowmobiles too now.....
 
Evanyj350 said:
I just ordered two 5 gallon cans of non-ethanol fuel through my hardware store supplier and plan on diluting the E-10 in my Yamaha, and my Honda 5hp on my dingy.  $55 per can.  (actually 4.5 gallons)  No other options nearby me here in Mass.  Both boats barely go thru a tank per season, so the shelf life of non-ethanol is important.  Especially when sitting over the winter in the barn....  Plan on running the non ethanol in my snowmobiles too now.....
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$12 per gallon for non-eth gas?  Good gosh. Does it come in gold plated cans?
 
Evanyj350 said:
I just ordered two 5 gallon cans of non-ethanol fuel through my hardware store supplier and plan on diluting the E-10 in my Yamaha, and my Honda 5hp on my dingy.  $55 per can.  (actually 4.5 gallons)  No other options nearby me here in Mass.  Both boats barely go thru a tank per season, so the shelf life of non-ethanol is important.  Especially when sitting over the winter in the barn....  Plan on running the non ethanol in my snowmobiles too now.....
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Is that engineered/synthetic fuel? I have seen that at the local lawn care dealer, they swear by it.I have not tried it because of the cost.
 
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