stihl 440 carb problem

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If there is a little ledge on the break, do as lone wolf said. Catch it with a dental pick or small screwdriver and pry/tap it counterclockwise. Otherwise small center punch, small left hand drill bit should do it, maybe an extractor if it’s being pesky. But shouldn’t take much to get it moving. I would really inspect the “seat” once you get it out. May be deformed from being over tightened.
 
I picked up a very well used 440, it starts and runs, but I think the low speed screw/fet snapped off? Do you agree? How do I back that out?View attachment 1141560
Carefully tack an appropriate sized welding rod to the stub. Would likely require a jig to hold the carb and rod.

Another option would be to clean it up real good with brake cleaner and glue an extension on it with some stiff epoxy putty.
 
Sorry, one more thing. It does start and run but it almost takes my hand off when I pull it. And I am finding TLC and feeling it out before I pull. I think halfway through the pull the decomp pops out, but it also does it if I don’t use the decomp
 
Sorry, one more thing. It does start and run but it almost takes my hand off when I pull it. And I am finding TLC and feeling it out before I pull. I think halfway through the pull the decomp pops out, but it also does it if I don’t use the decomp
Try pulling it over with the ignition switch off. That will tell you if it’s ignition timing related. Maybe the coil is going bad or the flywheel key has sheared. Excessive carbon buildup or flooding are about the only other two things that will cause it. Sometimes you just need to learn how to start a new or bigger saw. You might have to commit yourself to starting a little harder
 
Vapor locking will do that also from a carb not holding pressure and leaking ito the cylinder- positve pressure tested with a mitivac through the gasline fitting on your carb will tell you- should hold 15 lbs forever - positive pressure only - or it could be timing or both- had an 084 almost rip my hand off once
 
Hey, one more thing. This saw is mostly all there, but I don’t know what parts I’m missing. For example , has a very bent and beat up throttle rod. Is it just that wire or does it usually have the part in this picture that fits Over the carb studsIMG_2917.jpeg
 
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