When cold the saw won't hold idle (stalls) and does the WAHHH WAHH WAHH off idle when gassing (like it's running out of gas). Wide open is fine. I tuned it where it was running great, but the saw was warm when I did that. Runs just fine when warm, but when it's cold, nope. By cold I mean maybe 50-60*, not -20*... hasn't been that cold here yet! Also starts and stays running with wide open choke. All the other Stihls would burble and have to go to 1/2 choke for it to fire up. Wondering if I should pull the carb apart and rebuild it or if it's something else? Has 120-130psi compression, not "awesome" but not bad either. I suppose I could put a new set of rings in, the bore looked real nice.
How are the rubber parts? Have you tried changing up the fuel/plug, etc (starting simple). A saw will change tune a bit depending on fuel/temp/air, but it shouldn't be too drastic. It could be an air leak, but I think that would show up when it's warm, too. Does it idle pretty well once it's warmed up? How's the throttle response? Need an IPL?
The choke issue might be a simple fix. Remove the air filter and put the saw into full choke with the master control lever. It's possible that the linkage is bent and the butterfly is not closing all the way. As for the idle? It could also be related to the choke problem (if it's not the linkage). If the saw has an air leak it will not tune properly and also when on full choke, it can still run because the saw is getting more air from the leak (carb boot, impulse line, fuel line). On a saw that is approaching 10 years old, it's a good idea to change the fuel line, impulse line, and possibly the carb boot. Do you have a vacuum tester? (Edit: Buckthornbonnie- Great minds think alike)
If it starts without choke when cold and idles fine when warm. Sounds like it's to rich on the L side .
Yes, I took it off to paint it. I have the IPB most likely, the shop I'm cutting firewood/helping out does saw repair. I'm usually pretty good a sorting things out on small engines but this one it a bit weird. I don't want to just toss parts at it.
Remove the carb limiters.(if you haven't already). Lightly seat both needles and set them at 1 turn out each. Start there. But if you're tuning a carb that has old diaphragms, you're wasting your time. Buy carb kit first. Don't out rule a leaking welch plug especially if it's a ZAMA carb
Check what others said but I think its the carb. I don't think the L screw is adjusted right. Sounds to rich.
