Gizmo thanks very much for the detailed explanation. I worked my my through your list and number 5 was the problem! The cam was spinning freely which I should have noticed. Gave it a test run tonight and the old girl started first go. She idles beautifully and high speed is smooth. Tomorrow I'll mow the lawn with it to make double sure its all good but i can't see a problem!
All up this mower has cost me $25 with new blades, plug, air filter etc and the actual cost of the mower so m pretty happy.
It's going to one of the girls I work with so I think she will be happy plus I'll get a slab out of it!
Thanks again gizmo.