It doesn't appear that bell is from JFKs' boat (or if it was in the past, that photo shows it's now on a different boat).
Perhaps further research is needed.
You are likely correct on the bell...
Entirely possible. Both boats were heavily rebuilt and refitted several times since Kennedy's era. The Manitou has just gotten a complete refit and is now up for sale for $1.3 million.
I had the thought that perhaps JFK had donated his bell from the Manitou to the school ship . . . but that ship went down in 1961, so it's unlikely. However, it may have inspired it, as one of the people on one or the other may have either crewed Kennedy's boat which needs thirty crew for racing, or trained on the Albatross and suggested the bell's motto for the Manitou. Which came first? Who knows.
The odd wording of the phrase suggests an antique English and I have been trying to find where it may have originated in English Literature and getting nothing. . . it sounds Shakespearian.