I suggest you look at two things, Pete. First, check that the ignition timing is approximately right. I've explained how to do that in a previous post. Second, squirt a small amount of fuel into the carburetor air intake or the spark plug hole, and see if it then starts and runs briefly until it uses it up.
If it will start when you prime it in that way, then stop after just a couple of seconds, you've proved the problem is in getting fuel into the engine. If it doesn't start when you prime it, the problem is essentially spark or compression.
