Tecumseh hh120 smoking

My ss 12 runs excellent. But lately when I start it it runs perfect for about 30 seconds the suddenly starts smoking and smokes like crazy for about 2 mins. Then goes back to running perfect. It only does it on initial start up when cold. I have no clue what this could be. If it were rings it would smoke when all the time. I just don't understand how it goes from not smoking to super smoking back to not smoking. Does anyone have this same problem or ever had this problem

12, what color is the smoke ? is the crankcase over filled with oil ? if so does it smell like gas ? what oil are you using ? what does the spark plug look like ? check the crankcase vent tube and filter assembly , may be blocked or dirty. is it parked outside or inside ? just a few things to start looking at to begin narrowing down possible cause. > tim