tgrass462,
I had the similar question. Where is this gasket to get and how to replace it?
On my boat the gasket is leaking. My boat is docked and I made an easy test; pumped with a $10 hose/drill-machine-pump some water out of the ballast tank while the valve was tightly closed. The water came back in a short time to the previous level. The gasket is leaking.
I am going to get soon the boat out of the water for a bottom paint job and to replace the keel control cable. Thought that would be a good opportunity to replace the gasket too but could not find an answer where to get that gasket and how to replace it. Has anybody replaced the gasket and can give advice? Thanks,
Hart