Mystery Water Leak in the Cabin Top

[Vincentc]

TS Lee brought us about 10" of rain and an awareness that I have a mysterious leak inside and above the window on the stb side of the saloon.

see area in center of photos:

Even after the rain has stopped there is still water leaking in,

I cut away some of the wood to try and see where it was coming from but no help

When it rains the anount of water coming in is significant.

Any thoughts on how to find the source of this leak?

Thanks,

Vincent

 

[TROUBLE]

Vincent,

I discovered the same leak on the same side of my boat. I havent found it yet, but when i installed a cover on my fly bridge it went away. I think I at least know where to start looking when I am ready.

Art

 

[MikeP]

Don't know about your boat but the flybridge on our 1980 53MY has approx 200 screws holding it to the cabin roof. That makes 200 possible sources of water leakage...

Get your power screw driver out and a tube of 5200 and remove/rebed them all. That solved our similar leak problems...

 

[Vincentc]

Thanks,
The flybridge sounds like a good suspect. I know I have a water leak into the engine room in which water travels down the cables between the FB and the ER, perhaps there is some connection into the cabin top as well.

I removed the coverplate over the area under where the mast used to be, and did not see anything helpful, only another puzzle, what is purpose of the now capped copper tubing in the photo?

Regarding the leak, the wiring runs through holes in a stiffener just aft of the opening and those holes are sealed. Water may be running down that wiring and stopping at that caulked stiffener and running to the stb side. The location is appropriate.

Another project!

 

[TROUBLE]

Maybe there was an air horn?

Art

 

[Timeout]

That location on a 43DC looks like it may be from the handrail on the cabin top above. I'd try removing screws and rebedding. I doubt it is coming from the center area mast or horns but I've seen water take some real crazy paths. Other area I would check is lower helm windshield caulking. If you get water inside the lower helm area, I would also check around the compass.

 

[Vincentc]

Regarding the handrail, what is they say about great minds?

My first action was to remove the handrail and drill out the holes with a 3/4" Forsner bit, the core around the aft most hole was damp, but not soaked. The rest were dry balsa, which is pretty hard to find around any deck penetrations. I could not find any other deck penetrations close to and upstream from the leak.

Thanks for the suggestion.
Vincent

 

[Will]

We had a similar leak on our 43DC. It turned out to be from leaks in the pilot station windshield.
Will

 

[Vincentc]

Will,
That sounds plausible. The lower helm stb windshield gaskets do not look very good.
How did you find the leak?
Regards,
Vincent

 

[Timeout]

I don't believe the actual glass area can be at fault as there are no penetrations to below (I've had the glass out). The frame fits to the fiberglass and is bolted from inside the helm area. If any of the bedding or caulk under the frame has failed, water could find its way to the screw holes. I would just try a bead of caulk on the outside and inside edges where the frame meets the fiberglass.

 

[Will]

Vincent,
It was a few years ago but I think I found the leak by removing the overhead access plates in the salon overhead by the gauge panel and for the windshield connections (a few feet forward of the one for the gauge panel). To make sure, I ran some wide, blue masking tape over the joints between the windows and frames as well as between frames for the opening center window. The leak stopped. It stopped permanently when I removed and reinstalled the windows.
Will

 

[Bill Root]

The copper tubes you show under the mast access cover supplied air horns that were mounted on the cabin top of my 1973 43' DCMY now owned by Robby and Bren Bendall.

I agree with previous posts that based on the things you have already eliminated, the water leak is very likely coming from the bolts that hold down the windhield frame. On our 43 water would leak under the bottom of the frame then run through the bolt holes onto a headliner frame and down a side wall. Re-caulking the bottom of the windshield frame cured the problem for us.

 

[Vincentc]

Thanks,
I will take a look at recaulking the underside of the windshield frames. There are some leaks around the window frames as water does leak onto the fiberglass in front of the helm, but that eventually runs off onto the aft deck without any real problems.

The idea of removing and perhaps breaking the winshield glass troubles me.
Regards,
Vincent