Join Date: Nov 2004
Location: Cartersville, GA
Husqvarna engines are made to tighter tolerances and are designed to run cooler. This is why the manufacturer recommends running a 50:1 mix. A richer mix of oil (such as 40:1) will run in the trimmer, but it will make alot of smoke, foul the spark plug, and clog the spark arrestor in a short period of time.
I recommend you stick with the 50:1 mix, and use Husqvarna, Stihl, or Echo 2 cycle mix. All three of these 2-cycle oils are a high grade oil designed to run in air cooled engines and they should not be substituted with cheaper brands.