I have a mcculloch mac 3216 chain saw and have a problem. It will make one cut then boog down, if I open the gas cap it picks up and runs good. I checked the vent in the gas tank clean and clear. pressure is being built up in the tank. I rebuilt the carb and replaced all the fuel lines, not to fix it they were just dry rotted.
Not too familer with this model, however most Macs have a duck bill style breather, this will always create a pressure in the fuel tank, the impotant thing is that it does not have a vacume in the tank, if the rubber tipped needle in the carb is leaking the pressure in the tank may be enought to flood the carb and cause your problem, you realy need to pressure test the carb to check for leaks.
Husqvarna man
January 2010
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