Hey Daniele...or is it Daniel?...
no matter...I've seen similar set-ups on Hallberg-Rasseys, including
the lube resevoirs( on the rudder as well)...but I too have found them
to ocassionally be problematic, and even the smallest flaw causes
leaks...The fact that the grooves were caused by the seal bodies
suggest that there may have been an alignment problem which caused the
failure...so I would check or have it checked at your earliest
convenience to prevent recurrance...One thing I might suggest if you
have the room, next time you have it apart you can double up the "water
out seal", if not ,check with a seal distributor, they have "double
lip"seals available which effectively doubles the seals
abilities...I.ll keep an eye out for some kind of drawing or print...if
you go to my group (link below) you can e-mail me and I'll get in touch
if I can find anything.....
Regards,
markvictor

http://groups.google.com/group/badboatbiz