OcFerris
ArboristSite Lurker
Hi, I'm relatively new to CAD and some weeks ago it got the better of me when I bought a Stihl 011AV that looked like it hadn't seen a lot of use. I was told "it had gas sitting in it for a while but should be OK". Fair enough. I think it's one of the older models, all orange, before they changed to white but it does have electronic ignition. Anyway, I checked compression (145psi), flushed the tanks, put in a carb kit, cleaned the arrestor screen, new spark plug (the original looked fine BTW), new fuel line and just gave the saw a general going over and cleaning.
Well, that all resulted in a saw that starts easily but won't stay running. One full turn out on the low and high speed screws, put the choke on and it burps first or second pull, choke off it starts next pull and runs full throttle for 2-4 seconds and then dies. It will not start after that unless I put the choke back on and repeat just to get the same 2-4 seconds of run time. I had repeated this enough at one point that the saw was warm enough for me to start adjusting the low mix screw leaner. I kept leaning it out until it got where I could start the saw and keep it running and idling well enough. I put it aside and when I tried later to start it cold it wouldn't go. I checked the settings and found the low mix screw was only open 1/4 turn and the idle screw was all the way in. I know that's not right and it would not start again until I adjusted the low screw back out to something more reasonable.
I've since double-checked the carb build to be sure it was adjusted properly & none of the passages were blocked, checked fuel flow both with and without the filter, replaced fuel line again and tried running with the gas cap cracked (in case the vent wasn't working). No difference. Thinking the carb was junked I even replaced the original WT21 with a WA99 from an 010AV. That didn't help either. It's weird, the saw acts like it's running out of gas when I cold start it but the one time I got it running it sounded like it was running rich (heavy 4 stroking) but that could just be a high speed adjustment I never had time to get quite right.
I have not done a vacuum test as I don't have the equipment (yet). I do have a set of oil seals on order because an air leak is the only thing I can think of that I haven't tried. From what I've read about the symptoms of an air leak though, that's not my problem. I could be wrong. I have been before and it's likely it'll happen again.
Any direction you can give me would be appreciated. I'm not sure what to do next. Thanks!
Well, that all resulted in a saw that starts easily but won't stay running. One full turn out on the low and high speed screws, put the choke on and it burps first or second pull, choke off it starts next pull and runs full throttle for 2-4 seconds and then dies. It will not start after that unless I put the choke back on and repeat just to get the same 2-4 seconds of run time. I had repeated this enough at one point that the saw was warm enough for me to start adjusting the low mix screw leaner. I kept leaning it out until it got where I could start the saw and keep it running and idling well enough. I put it aside and when I tried later to start it cold it wouldn't go. I checked the settings and found the low mix screw was only open 1/4 turn and the idle screw was all the way in. I know that's not right and it would not start again until I adjusted the low screw back out to something more reasonable.
I've since double-checked the carb build to be sure it was adjusted properly & none of the passages were blocked, checked fuel flow both with and without the filter, replaced fuel line again and tried running with the gas cap cracked (in case the vent wasn't working). No difference. Thinking the carb was junked I even replaced the original WT21 with a WA99 from an 010AV. That didn't help either. It's weird, the saw acts like it's running out of gas when I cold start it but the one time I got it running it sounded like it was running rich (heavy 4 stroking) but that could just be a high speed adjustment I never had time to get quite right.
I have not done a vacuum test as I don't have the equipment (yet). I do have a set of oil seals on order because an air leak is the only thing I can think of that I haven't tried. From what I've read about the symptoms of an air leak though, that's not my problem. I could be wrong. I have been before and it's likely it'll happen again.
Any direction you can give me would be appreciated. I'm not sure what to do next. Thanks!
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