Bulkead leak

homerjack · Posted: Tue Dec 15, 2015 10:17 pm Post subject: Bulkead leak

Every time my cockpit accumulates water (rain), I get intrusion into cabin (a lot) thru door bulkead seam. There is a hairline crack there which I have sealed with heavy beads of 4200/5200 to no avail. What will it take for more permanent repair?

lloyds · Posted: Tue Dec 15, 2015 11:37 pm Post subject:

In my case, (although mine never leaked) the paint over the caulking used on that joint wasn't very well bonded and water could get under it. I would think if you removed all the paint you could see where the intrusion is. Maybe jack up your trailer pretty high and put some water on the inside against the bulkhead and see where it leaks out.

Sunbeam · Posted: Wed Dec 16, 2015 1:22 pm Post subject:

I can't speak directly to an '88, but I would think it might be similar to my '02, in that we don't have the "false" flat sole that is caulked in as the later boats do. Instead, at least on my boat, the cabin/cockpit bulkhead is fiberglass tabbed to the top of the cockpit "floor" which is also the upper skin of the actual hull. So no caulking is involved on mine.

If mine developed a leak there, therefore, what I would do to fix it on my boat would be to clean the area, sand/grind down to bare fiberglass, and then repair with biaxial fiberglass tape and epoxy resin. I would likely use the plain biax tape that does not have mat attached to it to reduce bulk, but as always, would have to decide for sure based on "being in there" and seeing it. I would not use any caulking at all.

Your boat may not be the same, but it seems it might be. If I come up with a photo of mine in that area, I'll come back and post it so we can compare/contrast.

Okay, here are a couple of photos. On my boat there is/was an installed drain right in the center/low point beneath the center of the cabin door. This simply connects the cabin to the cockpit when a plug is removed. The original one was a bit ugly and the fasteners were not the greatest, so I removed it and installed a new one. These photos were taken when it was out. So the "seam" you see just below the hole is the junction of the cabin/cockpit vertical bulkhead and the "sole" of the boat (which is the top skin of the actual hull).

The first photo is the cockpit side of it. The white stuff that looks a bit like caulk is a topically applied gelcoat to sort of hide the tabbing. The second photo is the cabin side. The bulkhead in this area was "hard" all the way through (i.e. all glass or gelcoat, no caulk or coring). Are yours similar? (You may not have that hole.)

homerjack · Posted: Wed Dec 16, 2015 6:26 pm Post subject:

Thanks so much for your post and pics Sunbeam. Yes my bulkhead is similar and does have the drainhole plug under door. Using FG tape and resin makes sense and doable. Will get to it this Spring. Thanks again.

Moxieabs · Posted: Wed Dec 16, 2015 8:45 pm Post subject:

Widget leaked from the cockpit to the cabin through the drain plug. This was because the screws and housing of the drain were not bedded/sealed with any sealer.

capt. meares · Posted: Wed Dec 16, 2015 9:51 pm Post subject:

I have the same exact problem right now. I also suspect it is an issue related to the drain plug. Is there balsa that I should be worrying about water intrusion in this location?

Sunbeam · Posted: Thu Dec 17, 2015 1:41 pm Post subject:

There was no balsa in this area with mine. As I remember (not at boat right now), you can see the "bulge" where the "wall" balsa starts (further up/over), and this did not connect with the hull balsa.

I didn't like the way my original plug looked and was mounted (and I wasn't sure at the time what was in there, core-wise - thought it might be an entry to the hull balsa), so I removed it and noodled some options. One was just eliminating it, two was a better/different plug, and three was a new version of the same plug but better installation.

1) I decided I like having the drain there.

2) Every new/different plug I tried had issues (because of needing to be so close to sole). I do think maybe a shaped fiberglass opening with a "Thermos plug" like on the transom might work and be slightly more elegant, but decided not to go through with that.

3) Ultimately I bought a new one of the original plug and did a better job of mounting it (3M4000 adhesive caulk, plus 316 stainless through fasteners with acorn nuts on the inside of the cabin).

But anyway, the upshot is that - at least on my boat - there was nothing there but fiberglass, so no "secret problem" occurring with the old/meagerly caulked plug.

capt. meares · Posted: Thu Dec 17, 2015 3:11 pm Post subject:

Good to hear there is no balsa there, i suspected there wasnt. The pictures above appear not to have balsa as well. I am cosidering removing this drain plug and sealing it completely, and move on.

Sunbeam · Posted: Thu Dec 17, 2015 3:18 pm Post subject:

capt. meares · Posted: Thu Dec 17, 2015 5:39 pm Post subject:

All good points sun beam. You've convinced me. This drain plug is the one and only area on the entire boat that has water or moisture collecting against the outside of it nearly 365 days a year. So why have something so vulnerable to leak, in this one area, if you never will even need it? I am glassing it over next week.