Leak at base of main bulkhead

[RustyB]

I have a strange leak that is showing up as discoloration around the base of the veneer covering the main bulkhead (see pic). I assume it is water coming down thru the mast but I can find no evidence of water at the base of the compression post, under the the cover in the head. There also isn’t any evidence of water on the wiring bundle in the bilge area under the head cabinet. Maybe the water is all being diverted to & soaked up by the veneer. Any ideas on on how I track down the leak would be appreciated. Thanks, Rusty

D2AB0F1C-4190-414C-A7DF-5DFC6B27BE87.jpeg (84.08 KiB) Viewed 2124 times

[Lagniappe]

I have the same thing. Only thing I figure is getting rain water down the mast into the bilge is somehow getting to the bulkhead. Based on other posts I cleaned out the drain holes at the base of the mast (no help) and I am making a Sunbrella cover for the mast roller furling.

[russp]

My totally uneducated guess would be water leaking in through a cabin top fitting or window, and running down the wall. Difficult to see how water could work its way upward when the bilge itself is dry. Can't comment on if possible for water coming down the mast to run horizontally along the underside of the cabin top and thus find its way down this bulkhead.

Russ

[tranquil]

I also have the same thing and appreciate all ideas as to the source and fix.

For that much water-stain it would be a significant leak and uncertain how to determine if it is from a window or something cabin top in that area.....

Thanks

[Guinevere]

Just a thought on finding the source...

I have tracked down a couple of mysterious leaks using newspaper or paper towel taped to different areas above and around the area getting wet.

For example, to determine if water is running down the outside of the veneered cabin wall, I would recommend taping (tight against the veneer with 3M blue painter's tape) a sheet or two of newspaper or paper towel 6-8 inches above this area. If water is running down, you should be able to see evidence of it even if the paper towel or newspaper has dried by the time you get to the boat to take a look.

This even works if you can wad a piece of paper towel into a tight spot where you think water may be leaking (e.g. if it's running in the channel at the base of the veneer from somewhere else and soaking up into it)

I haven't tried it (as our kids are long past the diaper phase) but I see some of the new diapers change color when they get wet. Not sure how much water has to soak into them to get them to change color (maybe too much for our use here) but maybe somebody with small kids or grandkids on the forum can experiment for us.

Bob

[RustyB]

Thanks everyone for your suggestions! I have to believe that it is someway connected with the mast wiring. Just can’t quite figure out how to get up inside there to take a look.

[Olivia Mae]

Last season I noticed a similar stain (though not as large as the one pictured) and wondered if it could be some sort of water leak. We do not have a furling mainsail, fwiw. Our bilge was dry and no sign of any water leaks, so I chalked it up to some old damage from before we owned the boat. Now I'm not so sure. I wonder if it could be caused by water leaking down from the sink in the head somehow. If not, maybe the mast base.

[nybor]

Yeah that is the first thing I thought of also. The other idea is the bilge pump discharge hose is so close to the location. I wonder how often the pump runs?

[modesid]

I had the same issue and found the water seeping from shower pan adjacent the bulkhead wall.
I cleaned out the old caulk and re-caulked which solved the problem

Wind Dancer
Haul 0011

[Olivia Mae]

We could have a winner! Thanks for mentioning that. Last year, I noticed that the shower pan in our boat had sealant cracked along the edge. I resealed it. That could explain why the shadow at the bottom of our bulkhead looked like old damage. No sign of any moisture on the veneer.