Hi all, Our M-17 "Star Cross'd" #357, has the cockpit scuppers that exit below the waterline. The water exits from the cockpit sole into the aft lazerette, where it then drains into two holes, connected by flexible tubing, to the actual drains. I think I remember reading that Jerry M. said they were copper tubes bonded into the hull. Now that I'm a saltwater sailor, I'm paying more attention to this stuff, about keeping the people in and the water out, since the ocean is vaster, deeper, rougher, and saltier than the inland lakes I started on. Has anybody ever inspected these thru-hulls and found evidence of corrosion? How safe are they, and how often should I inspect them? And if or when they do get corroded, what can I do to fix it? Copper is supposed to be a noble metal, but I think it suffers from saltwater corrosion just the same. <Whine on> If they were proper bronze or nylon thru-hulls, with inspectable and repairable seacocks, I'd probably feel a little better. As it is now, once the connecting hose from the locker to the thru-hull is in place, all the pipes are invisible. My biggest worry is that I'll be rummaging about under the cockpit, shoving gear around (oars, inflatable, spin pole, anchors, etc), and accidentally shove too hard on the hose/pipe assembly and crack it without realizing. <Whine off> As an aside, it just shows that you never stop learning about your boat. When we bought Star Cross'd, there were two little corks floating around the starboard gear locker, and I was never sure what they were for. I am now. I was out sailing in Santa Monica Bay, and opened up the aft lazarette. There was about 2-3 inches of water sloshing around in there, with the metal gas can getting a salty bath. And since when you're motoring, the vent hole is open on the gas can, in rough seas there's the opportunity for water to get into the gas. Apparently, the bottom of the aft locker is also below waterline. Duh, now the purpose of the corks becomes clear. I'll use the corks to plug the locker exits, to keep the sea out of the aft lazarette. I'll rig a quick release string so that if we take on water either going to weather or from rain or get pooped going downwind, I'll just pop the corks out and let it drain. Regards, John Fleming M-17: "Star Cross'd"
Hi John, I have the same arrangement on Grace (1983 M17 #400) and my drains failed. She lived in saltwater for 10 seasons before I bought her and corrosion took the thru-hulls out. I read the copper pipe replacement advice but 1-1/2" hose won't fit on 1-1/2" pipe (1-1/2" pipe is 1-1/2" inside diameter). The original thru-hulls appeared to be thin-walled aluminum tubing glassed into the hull. I believe the tubing was primarily the form around which the glass was placed as well as the attachment point for the flexible hose. I chose to replace them with 1-1/2" stainless steel tubing which has a 1-1/2" outside diameter and is much sturdier than aluminum. I ground out the remnants of the aluminum and glassed the ss tubing in place. I am confident that no amount of banging around will damage my new thru-hulls (at least not before the hull itself would fail). I think the original thru-hulls will last for the life of a fresh water boat (but I would still recommend checking them every few years), but they can and sometimes will corrode to the point of disintegration in salt water. I think I'll add some in line one way valves this winter to the hoses to eliminate the occasional backup of water into the cockpit. Your drains may be just fine but it would be prudent to pull the hoses off this winter and check their condition. Good luck. Mark Dvorscak GRACE
participants (2)
-
John Fleming -
Roberta Dvorscak