If anyone is interested in the oil leak problem i was having with my Optimax 250xl. It is finally solved !!
previous link is
The engine having spent more time being tapped by Mercuy's mechanics, than you could shake a stick at!! is now leaking oil FREE.
The oil leak was due to incorrect 2 stoke oil being used. I was using the Quicksilver DFi 2 stroke oil, my Mercury dealer sold me and it clearly says, that it is for use with Optimax engines on the side.
But it now appears that you have to use the Quicksilver Premium Plus type for 250 and 300 engines.
It has now been running for 2 weeks with the new oil and the leak has stopped :-)
However still nobody can tell me where the oil was coming from and why it was running out in that location ??