Our 1996 SM153 has a seawater valve for each of the toilets. Has anyone with these ever had either the valve or the thruhull fail? A surveyor just told me that he has inspected the same valves/thruhulls on other European boats like a Hallberg-Rassey where they had a failure. Ours are in good shape so I am inclined to keep them with a wood plug nearby in case of a problem. But if there is anyone here on the forum that has experienced an issue, I will change them out. Many thanks. 

Ian Townsend
Loca Lola II
SM153
On the hard in Maryland