Small Engine Parts Specialists
Note: The above video is great for tuning up your lawnmower. The
only thing that I would add is this:

If you don't have a puller you can always use what's called a
flywheel knocker that you screw on the end of the shaft. Be
careful not to damage the threads and make sure you screw the
knocker far enough, almost touching the flywheel. You then use a
pry bar and while you're pulling up on the bar you give a good
whack on the knocker and your flywheel will pop up. Sometimes
you have to do it two or three times. Be careful not to damage
anything with the pry bar.

For more complete instructions on taking a carburator apart check
the video on snowblower tune-up. Most carburators with float and
needle valve operate the same way.