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Can I use fuel prepared for a 2 cycle engine in a 4 cycle engine? Answered

I wonder if it is safe to use the fuel prepared with the 2 cycle engine oil in a 4 cycle engine lawnmower.



Best Answer 8 years ago

I do it frequently.

I use a 2 cycle weed eater but not often enough to burn the gallon of gas/oil I've mixed up in less than a month.  And I've found that after a month the old mix doesn't burn as well in my weed eater.

I also use a 25 hp riding lawnmower that burns plain gas.  What I do is pour the rest of the gas/oil in the tank and it gets diluted in the 6 gallons of gas.   I've been doing that for several years and no problems.

Probably not the best thing to do but then neither is pouring half a gal of gas/oil mix on the ground.

.  Yep. Dilution is the key. The more you can dilute the 2-cycle oil the better.
.  It's not the best idea to run oil through the carburetor, but, as Re-design points out, it's better than pouring on the ground or down the drain.
.  You may encounter a plug fouling problem if you don't dilute very much. Most modern 2-cycle oil is "ashless" which helps lessen, but not necessarily prevent, this.

You can, but you shouldn't: it won't burn right. One-off would not be much of a problem if the thing ran OK. If it didn't you'd have to drain the tank and re-fill...