Not sure why this little rototiller is 24:1, but that is what it say's.

So I am thinking about taking a 2.6 oz bottle this is for 1 gal. at 50:1 and using 1/2 gal. which should be 25:1 then,right? maybe use just a tad less than a 1/2 gal. maybe like .48 Gal.?

Any help

Sounds right to me. I think the older engines used 24:1 because the oil wasn't as good back then.

You have the math close enough 2.6 oz of oil in 64 oz of gas is 24.6:1.

24:1 is 2.66 oz of oil
25:1 is 2.56 oz of oil

To make 24:1 with 2.6 oz of oil is 62.4 oz of gas. I can't believe the rototiller would be sensitive to .1 oz oil or 1.6 oz of gas. I wouldn't bother as your measurement error will introduce as much variation - unless you are NIST exactly measuring everything.

Close enough, it doesn't have to be exact. If it comes into question err on the side of a little more oil, rod and crank bearings will thank you.

Thank you a lot guys.

You're over complicating this. Just mix 1 gallon of oil with 24 gallons of gas.

quote:

Originally posted by cas:
You're over complicating this. Just mix 1 gallon of oil with 24 gallons of gas.

Oh, sure. Post the easy way....

(So, smart guy, how much rototilling could be accomplished with 25 gallons of mix????)

You may want to use non ethanol gas, if available in your area.
My Mantis prefers this fuel.

I don't know that I've ever used it, at least for it's intended use, but a buddy gave me a mini-mizer, I think that was the label on it, a couple years ago, said that he saw them on sale someplace so got one for him and one for me. Have since seen them at the auto parts store and I think maybe at TSC. Anyway, it's a suction tube, sort of like an oversize hypodermic needle, with marks on it for just this type of measuring.

Walmart carries such an item. I bought one a while back... and haven't had to make a mix since of course.

For other mixes use a Ratio Rite.

https://www.amazon.com/Ratio-R...s-come/dp/B000I1YLGK

had one of these for years. It has always worked well.

quote:

Originally posted by Alpine79830:
Close enough, it doesn't have to be exact. If it comes into question err on the side of a little more oil, rod and crank bearings will thank you.

Back when I was a certified arborist, they had a chainsaw maintenance seminar put on by representatives from Stihl at one of the conferences I had to attend for continuing ed. While it may seem like more oil would be a good thing, they said the opposite is true. More oil makes the engine run hotter. Let's say you have 2 pieces of equipment ... one runs a 40:1 mix and the other runs a 50:1 mix. They said it would be better to mix at 50:1 for both than it would be to mix at 40:1. It seems backwards, but the guys from Stihl said they saw more 2 cycle engines fried from too much oil than not enough (I don't think they were counting someone who ran straight gas in one in that, though).

quote:

Originally posted by DougE:
More oil makes the engine run hotter.

With out a jetting change - more oil, from recommendation, is leaning the fuel mixture. Two strokes rely on the cooling from the incoming fuel charge. Too lean, too hot, piston seizes to the cylinder.

quote:

Originally posted by craglawnmanor:

quote:

Originally posted by cas:
You're over complicating this. Just mix 1 gallon of oil with 24 gallons of gas.

Oh, sure. Post the easy way....

(So, smart guy, how much rototilling could be accomplished with 25 gallons of mix????)

25 times as much as with one gallon of gas.