Thanks Bruce.
Carby appears to be flooding as plenty of petrol around where the gasket separating the 2 parts of the carby is. The tickler mechanism releases a lot of petrol and it goes everywhere, hard to tell whether petrol is leaking from gasket or overflow from tickler.
1 o-ring appears to be fine
2 2 holes are clear as they have had carby cleaner put through them as well as compressed air as well as thin wire.
3. Did take the seat out for better cleaning, feels firmly back in but how can i be sure?
4 governor works when i move the vane but when i move the throttle, the butterfly valve sticks, cannot see why, how is governor vane to be positioned?
Any help appreciated as i think i'm close but mower starts and dies after a couple of secs.