My engine mount (only one broke) broke in November 2006, after 150 hours in service. And we had sailed in pretty high seas and winds with the engine on for 20 minutes, which I believe its when it broke..luckily never had problems with the saildrive leak...
Anyway, the new mount was installed right then, and since then my engine only worked 50 more hours, most of them sailng the boat to where it is now in July.
So far so good, and I do check them periodically...
Thanks for sharing and explaining your case..I will transmit it to my Yanmar friends.
Why didn't you stop in Portugal to repair?? Yanmar here is very good.