I found this stuff this morning. You probably got one of these with the snowblower, which still doesn't answer your question, but makes me feel like I've done something.
I did find this too. It seems to be an exploded diagram of the parts for your engine. I've always found these things helpful in figuring out how things go together, because all the screws, nuts and bolts are shown. Then maybe I can figure out how they come apart.
Seems they're "Powermore" engines.
Found this somewhere along the line too,
..."a joint venture between MTD and Zongshen of China. Clearly no one (sears or MTD) will confirm this, but Zongshen makes MTDs Powermore engines, and it's documented that there is a significant relationship between the two companies. In fact MTD considered trying to purchase Zongshen a few years ago."
In case you want to invest in the company,
This one should make you feel good about that engine.