On Dec 14, 3:21*pm, Jay Chan wrote:
What is going on here?

You are seeing the engine's GOVERNOR in action. The governor senses
load on the engine, and opens and closes the throttle to maintain a
constant RPM.

When the RPM goes up, the governor closes the throttle.
When the RPM goes down, the governor opens the throttle.

It will run at "full speed" with the throttle 80% closed if you are
not blowing snow. When you start pushing through a snow bank, the
throttle opens up to wide open.

Is the carburetor needed to be cleaned one more time?

Probably. Some things need to be cleaned again, and it needs to be
reassembled correctly. From the sounds of it, the engine is not
getting enough fuel. That's why you have to choke it. Choke reduces
the amount of air coming in and brings the air/fuel mixture back into
balance.

Pay specific attention to the float, needle valve, and seat.