Outdoor Power Equipment and Small Engines - Ariens 10hp Tecumseh revs high and stalls

I have a 6 year old Ariens Sno-Thro that has always started easily and ran great. I do leave some gas in it every summer as I start it in July to run it for a while and have done this every year. Today after it started it would run for 10 seconds and then rev very high and shut off. It did this several times. With the throttle half way and the choke on the engine sputters but remains on, adjusting either of them stalls the engine out. Could I possibly need a needle valve?

May be time to take the float bowl off and check for some build up or varnish inside. At the very least you should check the bowl retaining nut to make sure all the orifices in it are clear. Sounds like your not getting enough fuel to the engine, and if opening up the adjustment is not making a difference, then there is a problem with the fuel supply to the carburetor or the orifices are restricted.