Chainsaw Repair

Carb screws (H/L) should not be down tight! You should get a small screw driver and slowly turn the (h/l) closed, just very lightly do not go nuts, just seat the adjustments closed. Then open each (counterclockwise)1.25 turns. Then start the saw and let us know the results.

OK, when you turn it on its side and it goes bad. Set it down and open the fuel cap then put the cap back on and start the saw. If it goes great then does it again, open the cap again and see if it starts and runs great. If so your problem is a clogged fuel/tank vent.

OK, it seems that you are getting the same information from this and the other site.

When the saw runs 'crappy', does it appear to be a lack of fuel or an electrical issue? I have just fixed an MS260 that was doing the same thing, it turned out to be a **** plug wire that would intermittently ground out on the cylinder.

I noticed that Dan Henry offered to look at your saw, perhaps you should consider letting Dan have a look.

well just to add an update
 today I had the saw out, was in low 70's all day here
 cut down and up 3 bigger hemlocks, about 300 dam branches per tree LOl
 and then into smaller pieces , as I stacked them to burn, on a safe day, or come winter when there is a lot of snow to prevent a forest fire !
 and the saw ran flawless all day??
 so didn't get to try any of the things to see if they made a difference(like if its vapor locking or)
 NOW I know I am not crazy, as this saw runs good some days, and then others like crap
 but today I couldn't get it to skip a beat
 which makes finding the issue's/problem even harder
 and even worse why I have kept it as long as I did, hard to be mad when it works LOl

 will try again in a few days
 I know last time it acted up it was in the mid 80's
 NOT that I think its temp matters, as it has acted up on me in colder temps as well as hotter, its just you never know what its going to do when you take it out, that is fustrating
 but will keep updated as I go
 and Dan, thanks again, and if I cannot figure it out I would still like to drop it off with you then!