Small Engines (Lawn Mowers, etc.): Snow Thrower Problem, oil fuel mixture, snow thrower

Question
Thanks Marc for such a quick reply. My carb is so difficult to get to, and the weather is so bad right now, would it be safe to try a carburetor cleaner added to the fuel? Also, as long as it runs half-choked, will that do any harm to the engine?

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Followup To
Question -
After just two seasons of successful use my Sears single-stage, two-cycle snow thrower has developed a problem. It will only stay running with the choke half closed and isn't at full power even then. The spark plug is clean and a fresh gas/oil fuel mixture is being used. Any ideas?
Answer -
If it will only run on choke, first try adjusting the mixture screws (initial setting of 1 1/2 turns out from lightly seated.  If the mixture screws have no effect, the carb has an internal blockage and will need to be cleaned thoroughly.  Hope this helps.

Answer
It won't do any harm but try to use as little choke as possible to avoid an excessively rich condition.  You can try a carb cleaner but there's a better chance it won't clear out any blockages, that's why a piece of tag wire (to push through all passages) is needed to clean a carb properly.  Hope this helps.