OK well I know have do it this time.After just taking a step back from it I had a good think as to what might be the problem.Then like in those Warner Brother cartoons the light bulb was above my head.So I pulled it apart for the third time.I even pulled the plate off and then started making up a new gasket,as the theory was the gasket I put on the first time wasn't doing its job.I don't even know where I got it from.My theory was replace the gasket as maybe there was a vacuum leak through that gasket,as that is what started this hole problem.So I got (Prum Prum) back together.Now I did cheat and added a little spray of start you bastard.On the first pulled it was alive!! I ran it for a few seconds,then stopped it.Primed the carby and started straight away.Them mowed most of my lawns (just lazy so I didn't do it all).Waited a few hours and started it again,all good.So mystery solved it was a vacuum leak through the first gasket I put on it.The second gasket is all good.Once again thanks for your help we got there in the end.
great to hear it doing the job again 
