# 2 stroke oil ratio question

#### Exhaustgases

On a bottle of Echo 2 cycle oil, it says 2.6 oz to 1 gallon of gasoline is 50:1.
The question is how come they base the ratio to the approximate weight of a gallon of water?
The info I find is water weighs 8.34 pound per gallon, and gasoline is about 6 pounds per gallon.
The oil is a bit heavier than gas. I am a bit sleepy so?

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I’m going to guess it is fluid ounces.

128 oz in a U.S. gallon. It’s based on volume, not weight.

128 oz is not a gallon of gas. It is 96 oz if it is 100LL according to info I found. 6 pounds per gallon.
I answered my own question, it is because the oil is heavier.
Sure based of volume but there is only weight listed on the bottle.

128 oz is not a gallon of gas. It is 96 oz if it is 100LL according to info I found. 6 pounds per gallon.
I answered my own question, it is because the oil is heavier.
Sure based of volume but there is only weight listed on the bottle.
by volume
gal = 128 fl oz
oil = fl oz
2.56fl oz of oil per gal =50:1

or it might be easier to think of it as 1 fl oz oil per 50 fl oz of gas.
so 128/50=2.56
but there is only weight listed on the bottle.
what?? 2 cycle oil is not by weight.
or are you talking about the AV gas. 100LL is not really "low" lead I wouldnt be using that in OPE and breathing it in.

128 oz is not a gallon of gas. It is 96 oz if it is 100LL according to info I found. 6 pounds per gallon.
I answered my own question, it is because the oil is heavier.
Sure based of volume but there is only weight listed on the bottle.
Again, volume. Not weight or mass, it's based on cubic inches. You did not answer your own question.

47 years ago in college a prof shared a simple ratio and proportion formula that I use every month in my pesticide and fertilizer applications.

In this example we are wondering how many ounces 2 cycle oil to add to a gallon of gasoline to get a 1 to 50 ratio, or 1:50.

Always use the same units - ounces, pounds, cups, whatever. 1 gallon = 128 oz.

1oz : 50oz = x oz : 128oz This is the learning point........ 1 is to 50 as x is to 128.

__1_oz___ = __x oz___
.... 50 oz. ...... 128 oz. .................. Solve for x .... 128 oz = x oz. ............ 2.56 oz = x (fluid ounces)
...........................................................................................50 oz.

So simple, we almost forget about it while learning higher math. Forget calculus and analytic geometry!

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128 oz is not a gallon of gas. It is 96 oz if it is 100LL according to info I found. 6 pounds per gallon.
I answered my own question, it is because the oil is heavier.
Sure based of volume but there is only weight listed on the bottle.
Ounces can be volume or mass. There are 128 fluid ounces in a gallon, no matter what it weighs.
There are 16 ounces per pound if you are talking mass.

47 years ago in college a prof shared a simple ratio and proportion formula that I use every month in my pesticide and fertilizer applications.

In this example we are wondering how many ounces 2 cycle oil to add to a gallon of gasoline to get a 1 to 50 ratio, or 1:50.

Always use the same units - ounces, pounds, cups, whatever. 1 gallon = 128 oz.

1oz : 50oz = x oz : 128oz This is the learning point........ 1 is to 50 as x is to 128.

__1_oz___ = __x oz___
.... 50 oz. ...... 128 oz. .................. Solve for x .... 128 oz = x oz. ............ 2.56 oz = x (fluid ounces)
...........................................................................................50 oz.

So simple, we almost forget about it while learning higher math. Forget calculus and analytic geometry!
Yes, same math I learned at school

2.6 fl oz. no weight shown

On a bottle of Echo 2 cycle oil, it says 2.6 oz to 1 gallon of gasoline is 50:1.
The question is how come they base the ratio to the approximate weight of a gallon of water?
The info I find is water weighs 8.34 pound per gallon, and gasoline is about 6 pounds per gallon.
The oil is a bit heavier than gas. I am a bit sleepy so?
Hey Sleepy, You better not do any cooking. A cup of sugar, a cup of flour, a cup of milk, etc. All different weight but VOLUME is the same. (LOL)

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Yes - this illuminates the confusion within the English standards of weights and volumes.

"oz" is both a unit of measure of weight AND volume, but they are not going to be interchangable.

Don't overthink this. Use the little bottle with a gallon of gas; that's the way they engineer'd the package. (they are using volume in this example).

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I thought this was posted in the wrong forum ! but i guess he is serious in his question.

Mix ratio's are calculated by volume not weight in this situation.

Its the mind blinders on, about fl oz, deal. I missed that and just saw OZ, just asking and not thinking or studying, its like that when you get older. Its something I should have known better. Totally missed an ML on the one I have. So thanks for the enlightenment.

Gotta stop breathing in that exhaust gas
Thats what my mom used to say, or was it gas fumes?

Or if you are in a metric country, 1 litre of oil in 50 litres of gas or 100 ml in 5 litres of gas. Adjust accordingly to match your gasoline volume.

by volume
gal = 128 fl oz
oil = fl oz
2.56fl oz of oil per gal =50:1

or it might be easier to think of it as 1 fl oz oil per 50 fl oz of gas.
so 128/50=2.56

what?? 2 cycle oil is not by weight.
or are you talking about the AV gas. 100LL is not really "low" lead I wouldnt be using that in OPE and breathing it in.
My Stihl fs38 trimmer goes like a scalded cat on 100LL.

My Stihl fs38 trimmer goes like a scalded cat on 100LL.
Didnt say it wouldnt run, I dont like to breathe in lead fumes.

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