Thanks Max and Norm,
Forgot to mention that at least we have shown that they will run with only 50psi of compression (as measured by my gauge) must admit I was a little skeptical. Would have got this far sooner if I had a little more faith in Max's judgement.
Thanks for the photos Max, unfortunately it appears that I have put the spring on correctly. I have been fiddling with the mixture screw, but it does what it is supposed to (lean/rich) but does not seem to help in terms of starting.
If its cold it will start on the first or second pull, as long as the throttle is only about 1/5 open, if it does not start by than it is flooded. You can see fuel spitting out of the carburetor throat from the first pull of the rope. If you jam the butterfly valve open it will start, (as long as the throttle is only about 1/5 open) The motor will not rev until it is warmed up, no doubt it is a Carby problem. I know 30% less about carburetors than I know about electronic ignitions which is 0.
If I can get a bit of time this afternoon, I will take the carby apart and have a look. I think in my case if a diaphragm gasket will fix it that may be the way to go. As I mentioned earlier when it is running it is never going to be a good mower. The engine runs smoothly but it has a rattle (probably the big end which had more play in it than I would like). A professional person would have replaced the oil seals when they had the crank shaft out, so I would expect them to start leaking. It still needs blades which are an odd size, the mounting hole is D shaped 9.3mm x 7.2mm which does not appear to be on the shelf at that hardware store. And it does not have a grass catcher.
Generally, I don't mess with carbys at all as you can usually get an aftermarket Chinese one off from eBay for $20.00 which is less than the cost of a kit for a genuine one. Note that I don't think I have ever had one that was as good as the original, but they do make things run.
I will let you know how it comes out but if I can manage to start it and mow the verge twice, I think I will be able to happy be finished with it.
