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?
stihl 440 carb problem
- Thread starter david newbie
- Start date
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small left hand twist drill
If you feel lucky, maybe tap it counterclockwise with a pick.
#2 take a dremel tool and the narrow cutting wheel. Cut down through the aluminum and down to where it puts a slot in the broken screw. Turn it out with a screwdriver.
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.
#3 go on Ebay and buy a cheap carb.
SteveSr
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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.
#4 send it to Steve
Thanks everyone. I’ll let you know how it came out (hopefully)
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
Check the metering lever height inside the carburetor. Common issue of them being too high. Adjust to even with top o carburetor body. Might be doing one today.
#5 send it to Stihltech
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 studs
