Link to: Stihl Fuel Article
There are issues being reported, and researched, on the use of ethanol fuels in small gasoline-powered engines.
Stihl provided an excellent article in their “Proline” publication dated Spring 2012, Issue 7 which I have scanned and attached. It contains useful information about the storage and use of ethanol-based fuels in their products.
While the article is specific to Stihl products, the information applies to other small engines as well.
In my personal experience, high-speed, high output 2 cycle engines used in chain saws, trimmers, and other equipment seem to be particularily sensitive to fuel quality, spark plug condition, timing etc. (This does NOT reflect on Stihl branded products, I have found this with other 10,000+ RPM engines).
I just purchased a 1 litre bottle of Stihl two-stroke engine oil. The directions for use in Stihl equipment state: “Mix the oil with fresh premium, or minimum 89 octane gasoline”. 89 octane is mid-grade gasoline in my area, not regular grade, and my understanding is that mid-grade gasoline is often only 5% ethanol so this recommendation gives you less ethanol and higher octane. I have decided to switch all of my small engines to premium gasoline. In my area, three major retailers have confirmed to me by e-mail that their “premium” gasoline does NOT contain ethanol.
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