Sooted Muffler

[Moss Man]

I was doing a winter cleaning on my saws today and when I pulled the muffler on the Husky 41 to clean the screen, the whole muffler and the screen were both covered in thick soot. Looked just like the end of a big ole diesel truck exhaust before they cleaned up the diesels. Dry soot, dry as a bone.

It has been running very well and I use Husky oil mixed at slightly over 50:1.

I thought if it was too rich it would have an oily buildup?

 

[rmh3481]

A two stroke chain saw engine does not have any valves like a four stroke engine would have. Because of this, a small amount of fresh fuel and air mix will escape the cylinder during the scavenging phase through the exhaust port. Since this is the way a piston ported two stroke engine is designed your never going to be able to fully escape carbon buildup. The best thing to do is what your already doing and that is to take some time and clean the exhaust out every so often. You can increase the amount of oil in your fuel which will keep the soot from forming, but instead you will get that dark black oily grease that will run down the side of the case. The oil is only part of the problem, carbon also forms from partially burned gasoline. Dont go any higher than a 50:1 mix, in the end you will only burn it down. Use the best air cooled two stroke engine oil that you can find and always use fresh gas. Keep your can capped and out of the sun when you can.

Best wishes,
Bob