Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

tore the carb off a friends 35 yr old chain saw and cleaned  and reinstalled it because it would quit when the throttle was returned to an idle. ended up being the vacumn tube at the back off the carb was bulged at the fitting and leaking air.installed new hose and put back together. set the mixture screws each to  1 turn out(couldn't get it started) and then to 1 1/2 turns and it finally did start. once running i adjusted the low and high speed to mid point of lean and rich rpm drop and it starts and runs great,only problem is it will not idle down like it should.it runs slow enough to keep the chain from spinning but the rpm's are a bit high.i can back the idle speed screw out so the throttle plate is completely closed and it makes no difference. i can slow the rpm's by leaning the slow mixture jet  so i beleave they are not damaged or the problem. that's about all i know how to do! anyone have any ideas why it won't idle down like it should?