Small Engines (Lawn Mowers, etc.): snowblower wont run, rubber seals, hello eddie

Question
I have an Tecumsah HSSK50 engine on my MTD snowblower that will only start with no choke and runs for 1-2 minutes then shuts off . I have cleaned the tank , carb (ALL ports and tubes),replaced the float ,seat and needle plastic emulsion tube and seals and had the dealer check my work and float setting . The plug is not wet when it stops and adding starting fluid as the engine begins to slow and stop does not help .Any help is appreciated.

Answer
Hello Eddie,

According to the information I have;  When the spark's DRY-
Check 1. Fuel supply and fuel cap vent, 2.  Restriction in Fuel System{Filter Screen}, 3. Carburetion Problem, 4. Poor Compression.  
Hopefully you didn't use a strong chemical cleaner when working on the carb, since it can act to melt or damage rubber seals and other parts of carb.

Good Luck,
Howard