Re: Measuring Fuel - Oil for outboard???
This boat has a large fuel tank I'd guess at 25 - 30 gallons...So the tank currently has 10 or 15 gallons (guesstimate) in it. What's the best method to make certain my fuel - oil mixture is correct when I don't know how much gas the tank will take at the next fill up?
If the tank is any shape with a flat top and bottom, and you have direct access to the fill hole, you can easily make a dipstick for it and can also calculate capacity. Use a piece of unpainted wooden dowling or other stick of wood.
The easiest way to do the dipstick is to completely empty the tank - either by siphoning or by running it dry or nearly dry. If you don't have a spare tank with you when you run it dry, just bring a gas can(s) with an accurate three or six gallons of gas in them. After you run dry, you can add that three or six gallons and make the first mark on your dipstick before you re-start your engine. If you mark a 6 gallon level, just 1/2 it on the stick for 3 gallons.
Total capacity can be shown by filling full from empty or calculating volume in gallons (convert cubic inches to gallons)
When you get to the gas station, you can complete your dipstick. Fill it up to that first three (or six) gallon mark on the stick. Fill it in 3 gallon increments and note on the dipstick with a pencil where the fuel level is each time. Use a different increment if it makes sense. Then, after the stick is dry, permanently mark it with felt tip marker - it will last forever.
Then, when you later go to fill the tank, dip it first to determine how many gallons of gas you'll need.... approximately of course. Add oil for that much gas. Use a measuring device like recommended above if necessary, or just do it in rough 3 or 6 gallon increments and use pints or half pints of oil. Eyeballing/estimating 1/2 pint is close enough, if you are at all careful. It will even itself out over larger volumes and not be an issue at all. Add fuel on top of oil.
Of course you could use any increment you want, but that would involve measuring ounces of oil rather than "pints" or "half pints". I personally believe that using quart bottles of oil and simply eyeballing half pints and pints on it are accurate enough, and that erring a little on the rich or lean side is good enough if the top-off isn't exactly on a 3 gallon increment. Note I said "erring a
little".
Hope it makes sense. I did that for years.
