If the engine will turn over without the plug in, it sounds as though you just have good compression. If the plug is out, put it back in. If you have a bench vise, clamp the shaft of the machine in the crook of the vise, ( the part under the jaws ), and try to start it. Keep the head away from the bench. I've experienced a weed whacker that was hard to start, and hard to hold, and that was how I got it started. Just clamped the shaft in the vise and it held the machine while I pulled the starter cord. If you don't have a vise, take the machine outside and lash it to a small tree. Take care to make sure that the head of the machine is away from the trunk of the tree, and give the rope a pull. If it doesn't turn over like that, take it to a service center. There would have to be something jamming in the starter mechanism. That's about all I can suggest.
Lew
May 2008
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