For years I bought the 3.2 oz. oil for my 40:1 chainsaw and 2.6 oz. for my 50:1 blower and string trimmer.
I marked 40:1 on the 1 gal. plastic can for the 40:1 and marked 50:1 on the other can.....easy peasy.
Simple math: 1 gal = 128 oz., 40:1 = 128 oz/3.2 oz and 50:1 = 128 oz/ 2.6 oz.
In a pinch I've used 40:1 in the 50:1
tools, just a tad smokey and harder starting due to less gas/more oil ratio and will likely foul the spark plug but no long term damage. However, using 50:1 in a tool designed for 40:1 for a extended period of time will likely damage it due to under-lubrication.
However, the last year or so I've been seeing these little bottles of 6.4 oz. stating it's for 40 or 50:1 mix, which is true BUT....how many of our current high school grads will get the math, and the mix, right?
![Wtf :wtf: :wtf:](/styles/ipcamtalk/xenforo/smilies/emojis/wtf.png)
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Here's a short sample of the Q & A about the mix and folks aren't doing well. The easiest of course, would be to pour the entire 6.4 oz. into a 3 or 5 gal. can and add 2.5 gal of gas for 50:1 or 2 gal of gas for 40:1. As a homeowner I only want/need a gallon of mix sitting around but I can see where someone cutting/trimming for a living can use 2, 2.5 or more gals of the proper mix with them.
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