So I still do not see the central question that SFS and Adelboat asked -- Where? JosefR - how did the project turn out? Pictures?Did he tell you WHERE on the boat he would put that clamshell vent?
I've disconnected the stanchion vent on my Catalina 36 (MkII) and will seal the through-deck hole which has caused some water intrusion to the deck (repairing that following Mainesail advice). Currently, the 3/4" vent line runs forward from the saloon waste tank, and up in cabinets behind the head. I could just bend the vent hose 90 degrees and drill a hole inside that cabinet (option 1). With a bit more work I could backtrack the line back into the saloon area, then go through the forward cabinet on the port side, but that would mean drilling through a teak finish on the back wall of that cabinet (option 2). This would shorten the vent by 3-4 feet, but also lower it on the hull below the sealed ports which I occasionally splash for failure to reef, and I don't want to ingest seawater through the vent. Is shortening the run by 1/4 going to increase the tank aeration? Anyone with a C36 have some advice? I don't see the need to increase the size of the vent to 1" as I have no tank smells following Peggy's excellent guidance and a shot of CP at the end of each day.
Also, for those who have done this modification, did you buy a new stanchion to replace the "vented" one, or can I just use a hacksaw to remove the through-deck vent?