Hi tiger. The best place to start would be a few pictures of your machine, if that's possible. Also the model type and code may be needed to correctly identify the engine. When you said 'reassembled' the engine, did you clean carby like you mentioned before, if not I'll go overit quickly.
You have already diagnosed that it is a fuel issue, by putting some fuel into the cylinder. If you have a pulsa prime carby, firstly start by taking fuel tank and carby assembly off the machine, strip, clean and flush, and replace diaphram and gasket with a new one. This is should fix the fuel issue.
As for the over revving, it is super common on that machine that the governor/throttle plate gets bent. This will either loosen the spring and thus make the engine run at very low rpm's. Or it can bend the other way and put tension on the governor spring, this may have happened to you. Inspect the tabs for any bending, and operate the throttle (when engine is off), and look at the governor spring.
As for the starter cord, it's hard to tell you what's wrong, without a photo. It does sound like something is warped or binding. Make sure not to over tighten it. But we have a lot of knowledgable people here, so maybe they would know.
Good luck mate, I'm sure you will figure it out.
