Thanks much for the good opinions and reasoning so far. My only reason for considering not fixing them, but sealing them, is that if this happened once, it can happen again.

I agree that replacing both fittings and hoses, new hose clamps, etc., reduces the risk of another failure, so I will see what it will take to make that happen and consider further.

I am working through multiple issues right now, but a cursory inspection of the geometry involved reveals to me that the cockpit scupper is only about 12 inches higher than the transom drain to which it is connected on the opposite side of the boat. When you do the trig, that means at angles of heel close to 15 degrees, the scupper and drain are at the same level, so no draining will occur.

I do need to make more careful measurements when I can, but now I am back to thinking they serve no real purpose.

Two things:

1. Here are 2 pics showing the external location of the scupper drains on the transom, and the internal pic showing the broken drain fitting.

2. I made more careful measurements today of the height of the scupper in the cockpit relative to the transom drain, and the horizontal distance between them (port scupper connects to starboard drain and vice versa). After doing the trig, I conclude that the scupper won't drain after approximately 12 degrees of heel.

I would love for a skipper with scuppers like mine to review it independently and render an opinion. Thanks!

More updates:

1. The port transom drain is connected solely to the propane locker.

2. The starboard transom drain (the one that broke) is teed to both cockpit scuppers.

I am going to email Gerry Douglas and hope for a reply.

Thanks for your input, Joe. Actually, the bottom of the propane locker is below the cockpit scupper, considering that the cockpit sole slopes up at that point.

The only time the scuppers are useful is when the boat is heeled and there is a small amount of water that cannot easily drain out the open transom. The boat is only heeled to one side at a time, so I am not sure how you double the amount drained through the scuppers.

I was very pleased and grateful to get a reply today from Gerry Douglas (C36 designer and principle at Catalina Yachts).

He said that the scuppers are there solely to drain the small amount of water that might accumulate while you are heeled. If you can live with that small amount, no negatives to removing the scupper drains altogether.

I realize the failure of the transom drain fitting might be a low probability event, and would likely not occur again after replacement, but if I can simply plug the hole to make the chance of failure almost zero, I may choose to do that. Obviously, I would have to plug the two cockpit scupper holes, too.

My wife is a bit distraught over this. Maybe if she makes the decision it will give her some ownership in the outcome and restore some confidence.

Status report:

I obtained a marelon thru-hull fitting from Forespar, and put the system back as it was designed.

Details:
I cleaned out the cracked pieces of the old fitting, only to discover that the nut on the inner surface was not coming off (probably 5200 adhesive). I managed to screw the new fitting into the old nut and sealed it well on the bore and the large mushroom head with adhesive. I know how critical this fitting can be, but i am supremely confident that the adhesive alone will do the job should that old nut pose a problem.

The ridiculous part was the hose. My 102 pound wife crawled into the aft compartment, and with me working from the top, we together removed hose clamps and shifted the hose upward enough for me to handle the T-fitting at the starboard lazarette. I was able to get the old short section of hose off with the broken thru-hull barb, fit a new piece of short hose, and replace all the hose clamps.

All Diane had to do at that point was put the short hose onto the new thru-hull fitting barb and tighten the hose clamps, which she was able to do.

After we were done, however, she said I need to plug it from the outside anyway so if the hose or fitting barb should fail, we will still not take on water. That means plugging the 2 cockpit drains, or else I will have the extra weight of water sitting in the hoses forever and putting extra strain on the fitting.

I guess that won't be too hard to do.

[QUOTE=bstreet;20587]In retrospect though, and since you are plugging them anyway, would it not have been easier to just pull out the thru hulls, hoses, etc. and glass over all the holes?[/QUOTE]

Well, Bud, your logic is sound. I surely would not have gone to all the trouble we did if I had known that the admiral was going to insist on having them plugged anyway. I am tolerating this recent and hopefully temporary extremism on her part only because this recent flooding event really had her scared.

We're going back to the outer Bahamas next spring and for some reason, deep water crossings with a boat that almost sank has her worried. If I can put both a belt and suspenders on this particular issue, then I will do it and hope time eases her worries.

True, these drains exit the transom close to 12 inches above the unloaded waterline. Add the dinghy on davits, cruising gear and provisions, and start moving at speed through the water (so that the stern wave rises under the counter of the hull), and those holes are close to the waterline.

Now, heel to starboard and the drain thru-hull is several inches below the water level.

So, at least she won't sink at the dock for that reason.

Glad my post helped someone else. It is really a difficult area to see, let alone work in.