How do you remove the butterfly valve from a small engien carb?

I have a stihl FS-85 string trimmer with a zama CQ1 carburetor on it. How is the butterfly valve for the throttle removed? Mine is stuck and I cannot get it to move for anything. So I want to try removing the butterfly valve and can't get out the shaft that the valve screws into.





Thanks|||On most of these small engines, the screw that holds the butterfly sticks through the shaft a little and is "spread" after installation to keep it from working loose and getting sucked into the engine.


The PROPER WAY is to grind off the protruding screw shaft first, VERY CAREFULLY so you don't damage the shaft, then use a penetrating oil if it won't come out to loosen it.


Use a NEW screw when you reinstall it the butterfly, and spread it after installation.


Since the head is on the side toward the engine, you will need to remove the carb.


IF the shaft is "frozen" use penetrating oil to loosen.|||Usually one or two screws hold it to the shaft, (takes a small flat-blade).|||Squirt some Kroil on it and let it soak. In a day or so if it doesn't come loose try a little bit of heat.