I bought an older Stihl 038 magnum off a neighbor who was moving a few years ago and wouldn’t need it anymore. Today, the muffler rusted off. Aside from being ridiculously loud, is there any reason I shouldn’t/can’t run it like this?
Two strokes rely on some back pressure to make them run correctly it could actually make it run lean and have less power
I have more than one vintage saw that has what's called a stack "muffler". Its nothing more than an extension of the exhaust port with some large slits to keep things out. You can see the piston plainly through the end.
This is factory? I'm sure the saw(s) have been jetted/tuned to be ran that way...gotta be freakin loud too!
No it will not hurt it and I see the diffuser is still in place. Then there is the danger of a fire hazard with it open like that. I would try and find another muffler for it if it were mine.
The old saws also ran as much as 16:1 mix also the oils were not as good but it was tough to run lean with those heavy mixes and there scavenging system was not near as good but I know from racing Karts a expansion chamber gave the engines way more torque and power as opposed to just a turn out on the engine I ran mac101b engines and it made a huge difference JB
Lean air fuel ratio and lean oil to gas ratio are two different things. You can lean out an engine and ruin it on any oil / gas ratio. In fact as you go up in oil content, ie, 16:1 vs 32:1, you have leaned out the air / fuel ratio by displacement of some of the fuel with oil. You would then need to richen the jets to account for this. I have several saws that require 16:1 according to the manuals. They all get the same oil mix as my new saws.
This is my Remington SL-9 with its stack "muffler". I have a later model with a box muffler. The unit pictured is the loudest saw I own currently.
If anyone coming to Denny's GTG interested in running a dinosaur like this I can bring it and a couple others I have.
