For the Mike E post, there are actually 10 quarts in 2.5 gallons, which means at 32oz per quart, that's 320ozs. Mix at 40:1 divide 320/40=8oz
For 50:1 divide 320/50=6.4oz
His math is right, but the ratio was wrong. 192ozs is for 1.5 gallons.
Bob J
November 2013
Mcculloch saws were always a 40:1 mix. Good luck with the owners manual!!
b bowman
November 2009
There's 128 onces in 1 US Gal. so find out how mush gas you want too mix then divide the oz's of gas by the Ratio your engine calls for!
Example: A 2.5 Gal gas can has 192 onces and you need a Mix @ 40:1 divide 192 by 40 =4.8oz's
If mix is 50:1 divide 192 x50 =3.84
Mike E
September 2008
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