When you put Sea Foam in it takes some time for it to work.try again in couple hours,then again,Then in the morning if it doesn't run.If it has a choke put it on 1/2 choke when you give it the gas.

rl it's the ethanol in the gas causing your problem. With luck,the seafoam will get you through but I'm betting you'll have to strip the carb down and give it a deep cleaning. What's happening is the main fuel circuit is clogged and can't deliver enough fuel to match the air when you hammer the throttle. Our techs see that exact issue at least 10-12 times every week on 2-stroke equipment.

I doubt that the carb has a float.  Chainsaws have to run right side up and sideways....carbs with floats can't do that.  The carb has a diaphragm fuel pump and a diaphragm to control the fuel flow with a needle and seat......and these gum up and/or become stiff when the saw sits with fuel in it for extended period of time.

Don't screw around with SeaFoam or even try to run the saw with old fuel and a cruddy carb.  A 2 cycle engine is lubricated by the fuel/oil mix and if you run it lean it will not get enough lubrication and can sieze the piston.

You also don't need to run a 16:1 oil mix anymore.  That was written o in the days that we used to just dump 30 weight non detergent oil in the gasoline and makes lots of smoke while cutting.  Today the modern 2 cycle oils are much improvecd and a 50:1 synthetic mix oil will work just fine in that saw when the carb is repaired.

Listen to ZAR....he repairs these things for a living, and I did the same 35 years ago.  The majority of saw repairs are done because the saws just sit for years between use.  When you are done using the saw and you are not going to use it for a while, dump the fuel out of the tank, then start the saw and let it idle until it runs out of fuel.  The factory manuals advise you to do that if you are not going to use the saw for more than 2 months.

bill67 wrote on 04/05/13 at 05:33:06:

SeaFoam might work to clean up some things - but it won't work on hardened diaprhagms.  Running a 2 cycle engine lean while tryig to clean out the carb is not a good idea, as a lean running 2 cycle engine will not get enough oil and can be damaged.  It is not worth the risk.  Sometimes you just have to do the right thing and make a proper repair.

Dave wrote on 04/05/13 at 05:40:45:

Sea Foam has oil in it and its recommended for 4 and 2 stoke engines. I live in a boating and snowmobile area and a lot of them are 2 cycles and people here use Sea Foam.

rl153 wrote on 04/05/13 at 06:16:24:

Thats about the right amount of Sea Foam,If it says 16-1 thats what I would use.

Don't listen to bill67 on the Snake oil cure all of SeaFoam,  Do the right thing and pull the carb and clean it properly and replace any hoses that have become brittle or are starting to deteriorate.  Your clunk pickup also sometimes it's a stone type filter for the clunk pickup may also need to be changed as well in the fuel tank.

bill67 thinks seafoam and klotz oil will magically cure anything when it comes to engines, he even claims that if you use them you will never have to change your oil.  

If something like that had truly been invented all other brands would now be non-existent and engines would last forever, which we all know is not true.

If after cleaning your carb and adjusting it properly plus the air filter cleaning if it's foam or replacing if it's pleated paper, it still doesn't run properly then your issue could be a little more involved meaning the reed valve has gotten stiff or cracked, which could cause the same symptoms.  I had this happen on a weed eater type engine once that I had converted to glow fuel for use on large scale R/C airplanes.  It's a fairly simple fix but you gotta tear down the engine to replace the reed valve.

R.F.