I have a 71 or 72 snow blower from Ariens with a 6hp Tecumseh engine

Model: 910995 Serial: 013960

Engine model: H60-75343J Serial:1319R

The engine starts up fine and idles decently. The trouble comes when I open the throttle. If open it like normal, It starts backfiring out of the muffler and the carburetor. It will run like this with the choke fully open. I just rebuilt the carburetor and got brand new gaskets, cleaned the mating surfaces and re installed and it made absolutely no difference, It still wont run properly. I can play with the upper screw (not the idle speed adjuster) and the screw at the bottom of the bowl until the cows come home and that doesn't work either.

Last winter I used it like this, and I couldn't get the choke anymore than halfway open.

Some one please help me, winter is on its way to Wisconsin and I am going to be completely screwed without it.

These are amazing snow blowers that power though anything and built like a tank. This, as well as my budget restrictions prevent me from buying a new one.

Any help is greatly appreciated.