So way back when, needed a saw, farm use/firewood too but not then, researched a little, ended up with a Stihl MS 390, this was '02. I'd say after 12 years of use, it's paid for itself, done what I've needed, I'm not a logger, I don't cut daily, so this models description/1127 series Stihl family of saws seems to live up to its name.
Over time, it did not look like it did when new, usually well kept, but hauling in a loader bucket, it took a short fall when relieving an ice covered tree limb over the un-energized power line close to the weatherhead, after an ice storm, I had been meaning to make it right since.
So I started with a new engine housing, handle, flwyheel cover, sprocket cover, fuel line etc. it's been said these are difficult to work on, I did not find that to be true, there are a few things to know, the bar stud has loctite, you have to be creative to get it out, 2 bar nuts or flat spots cut with dremel, on this one I did not have to cut the flat spots for a 10mm wrench. Clutch is left hand thread. With a new engine housing, you have to tap the new holes for the screws, use care on that and it will work fine, common sense, 1/4" drive ratchet or screw driver handle with T-27 driver. Set the flywheel to coil gap with a twice folded 8"x11" sheet of paper, ( as if you were to put it in a standard envelope. New air filter, I've cleaned the old one for 12 years !!!
Boy do chainsaws get filthy, everything is covered with sawdust fines soaked with bar oil, compressed air with a fine stream tip is your friend, so is a nearby garage door to blow off the oil soaked/caked parts. Now I know why I like bar oil, it does not fling as much as other alternatives, besides what it does for the moving parts.
I was able to carefully check the carb boot to the intake, good, same with the impulse and the bar oil line, all looked fine, stretched to look for cracks, holes, carefully cleaned and examined, all pliable, and fine, I was going to just replace all of them, but they felt just like the new fuel line, if any do fail, its not that difficult to change any of them.
I am aware that this engine has plastic bearing races, which can be detected as defected by shaking the engine while out, you can hear the ball bearings moving freely, mine was good on that, the piston and cylinder look fine, still have the machining marks on the piston, I could detect no wear and by feel/listening, seemed like good compression, sure you need to test to be sure. I attribute the lack of wear to using stihl 2 cycle oil, precisely the correct amount of gasoline and oil every time, I even rinse the little jug of it with gas to get the remaining oil out, cleans it for the recycle bin, so a win-win on that LOL !
From what I saw while doing this, the materials the saw is built from are decent, all the parts are marked, there are no real pitfalls, well that's a dumb design etc. I like the brand and of course it could be another, its fun and almost a hobby but there's a few things I own that I will use exclusively, all their products. So on this saw I use nothing but Stihl products. My John Deere lawn tractor the same, these 2 and my Troy Bilt Horse, rototiller get meticulous care, seems to work, and being small its a little bit of fun. Stihl is an expensive brand name for sure, parts exclusive to dealers and probably a lot of stigma, like other brands with the same status. I would never criticize another brand until I used it extensively and took it apart and re-assembled it, knowing whats different, what I like and don't like. I enjoyed this build for some reason and thought I'd share the experience, more important than brand or what have you, it was a fun little project.
Finally time to cut again, may not look as clean again, but I will be a lot more attentive to it's care, use and most importantly its maintenance which I did all along, just did not look it LOL !
PS, I even transferred stickers/decals to make it correct, new engine housing has a blank spot where the serial number goes, so I recorded that took photos, will have to mark it somewhere hidden.
Over time, it did not look like it did when new, usually well kept, but hauling in a loader bucket, it took a short fall when relieving an ice covered tree limb over the un-energized power line close to the weatherhead, after an ice storm, I had been meaning to make it right since.
So I started with a new engine housing, handle, flwyheel cover, sprocket cover, fuel line etc. it's been said these are difficult to work on, I did not find that to be true, there are a few things to know, the bar stud has loctite, you have to be creative to get it out, 2 bar nuts or flat spots cut with dremel, on this one I did not have to cut the flat spots for a 10mm wrench. Clutch is left hand thread. With a new engine housing, you have to tap the new holes for the screws, use care on that and it will work fine, common sense, 1/4" drive ratchet or screw driver handle with T-27 driver. Set the flywheel to coil gap with a twice folded 8"x11" sheet of paper, ( as if you were to put it in a standard envelope. New air filter, I've cleaned the old one for 12 years !!!
Boy do chainsaws get filthy, everything is covered with sawdust fines soaked with bar oil, compressed air with a fine stream tip is your friend, so is a nearby garage door to blow off the oil soaked/caked parts. Now I know why I like bar oil, it does not fling as much as other alternatives, besides what it does for the moving parts.
I was able to carefully check the carb boot to the intake, good, same with the impulse and the bar oil line, all looked fine, stretched to look for cracks, holes, carefully cleaned and examined, all pliable, and fine, I was going to just replace all of them, but they felt just like the new fuel line, if any do fail, its not that difficult to change any of them.
I am aware that this engine has plastic bearing races, which can be detected as defected by shaking the engine while out, you can hear the ball bearings moving freely, mine was good on that, the piston and cylinder look fine, still have the machining marks on the piston, I could detect no wear and by feel/listening, seemed like good compression, sure you need to test to be sure. I attribute the lack of wear to using stihl 2 cycle oil, precisely the correct amount of gasoline and oil every time, I even rinse the little jug of it with gas to get the remaining oil out, cleans it for the recycle bin, so a win-win on that LOL !
From what I saw while doing this, the materials the saw is built from are decent, all the parts are marked, there are no real pitfalls, well that's a dumb design etc. I like the brand and of course it could be another, its fun and almost a hobby but there's a few things I own that I will use exclusively, all their products. So on this saw I use nothing but Stihl products. My John Deere lawn tractor the same, these 2 and my Troy Bilt Horse, rototiller get meticulous care, seems to work, and being small its a little bit of fun. Stihl is an expensive brand name for sure, parts exclusive to dealers and probably a lot of stigma, like other brands with the same status. I would never criticize another brand until I used it extensively and took it apart and re-assembled it, knowing whats different, what I like and don't like. I enjoyed this build for some reason and thought I'd share the experience, more important than brand or what have you, it was a fun little project.
Finally time to cut again, may not look as clean again, but I will be a lot more attentive to it's care, use and most importantly its maintenance which I did all along, just did not look it LOL !
PS, I even transferred stickers/decals to make it correct, new engine housing has a blank spot where the serial number goes, so I recorded that took photos, will have to mark it somewhere hidden.