Chainsaw Repair

bob.........the carb stuff is nothing fancy.  the camera i left at work, will post them tomorrow.  the pics will explain it a whole lot better then i can do with words.

idea is get better mid range and WOT adjustability.  the idle speed screw is turned in on the stock carb say "x"amount of turns, the air goes by the small indent on the butterfly, but quite a bit of the air gets by the butterfly by going around the outer circumference of the butterfly.  the combined air helps set the mix at idle speed.

i turn the idle screw out as many turns out it takes to just close the butterfly completely.  (what that does), now the only air that can get by the butterfly, is going through the small indent.  then i drill a few holes in the butterfly, which will control idle speed air only.  thing is, you have to guess how big and/or how many.  tune the saw as usual, get it hot, then tune the idle speed.

thats the gist of it.  right now, i have too large and/or too many holes.  idle leans out and speed goes up.  plugging the holes one by one, then test/tune, after each plug.  then i'll get a new butterfly.  then tranfer the best final best size hole to it.

right now, it runs very well, except for the idle.  the low speed is more like an intermediate jet, the high is still the high, but the hole is now like an fake idle jet.  hope it makes sense.  if not, the photos hopefully will.  some photos show some mistakes and bad guesses made along the way made as well.  but it's all part of the process.

regards
-joe