drip loop in mast internal wiring

[HerbertFriedman]

In this rainy season in the SF bay area, I think I have found a new leak and am asking if anyone else has seen this or, better yet, fixed it.

I notice a leak coming from the head liner where the (keel stepped) mast passes through the cabin top. I do get quite a bit of water in the bilge during a hard rain, exiting the very bottom of the mast (in a bilge area) through a small hole where the UHF antenna wire exits. No problem, the bilge pump takes care of this water.

I had the mast unstepped two years ago to replace the standing rigging and when the mast was re stepped, a cylindrical rubber sleeve was put on the mast and then folded back on itself (hose clamped well) to provide, what I consider is the best possible seal for the mast -to-cabin top penetration. However, I still get a water leak as evidenced by water on the cabin table and sole, not a whole lot but enough to damage the finish.

Under the trim boards surrounding the mast and screwed into the inside of the cabin top, is a terminal strip with wires going to the lights on the mast. I think water is dripping down these wires and since there does not appear to be enough slack for a "drip loop" inside the mast, the water follows the wires and finally end up on the cabin table and sole.

Have any of you seen this and if so, any ideas, e.g. putting to seal the hole in the mast, or lengthening the wires to proved a drip loop, etc??

 

[Loren Beach]

Yup. We had to solve this problem right after we trucked out boat home from SF in 1994.
There is a drilled-out hole in the mast wall, just above your head liner. The 12 volt and wind transducer wiring all comes out there and goes about a foot or so to the side, to a terminal strip, where those wires meet up with the wiring from the panel.

The prior owner had ignored the rain seeping out, and onto the headliner, and running over to the top of the interior cabin side, and down the teak veneer... (sigh).
Once I removed the corroded-out zipper pulls on either side of the mast penetration, and figured out what was happening...... I used some clear silicone sealant globbed/inserted/mashed into the wires and the hole sides to seal it so that future rain water would all fall down to the step and into the bilge where it belonged.

Only ameliorating factor is that blame can all be assigned to the prior owners, those most heinous individuals that we all blame.... !

Betcha that some of the same guys rigged out both our boats, and really, they should have plugged that rain leak before commisioning was completed, and the boat was handed off to the dealer. (heavy sigh)

 

[HerbertFriedman]

thanks for sharing, that is what I need to do, I was not sure I could get to the hole in the mast. Did you use just silicone out of the tube or were you able to thicken it? I was thinking of something like "plumber's putty"/

 

[Loren Beach]

thanks for sharing, that is what I need to do, I was not sure I could get to the hole in the mast. Did you use just silicone out of the tube or were you able to thicken it? I was thinking of something like "plumber's putty"/

I used the sealant as it came out of the tube. Protect the surroundings and maybe wear rubber gloves.
As always....

 

[Kenneth K]

I had a very similar leak in the same area. The culprit was the tri-plex wire going to the steaming/deck combo light on the mast.

The rusty terminal block to port of the mast should have given it away, but it took me 2 years to find the source:



Details here: https://ericsonyachts.org/ie/threads/pesky-leaks-a-little-progress.16373/

 

[HerbertFriedman]

Kenneth, I think you are saying that the water leak from mast wires going the terminal strip under the headliner at the port side of the mast, was from inside the white jacket not outside it. If that is the case, then making a drip loop inside the mast will not help. And sealing the hole in the mast will not help either. If you manage to apply some "goop" to the wires as they exit the white cover, then eventually water will fill up the entire run of that wire bundle and be trapped. Not sure that is bad if the insulation on all the wires in that bundle is firm.

I guess the real fix would be to cut back the white cover so that the water drips into the mast, not the headliner. That water mixes with the water drip inside the mast, then into the bilge where the bilge pump can get to it. But I dont think I have enough access to cut the white cover back that far, sounds like that kind of fix would have to wait until the next time I pull the mast.

How did you solve the this dripping cover problem?

 

[Loren Beach]

Herbert, I really doubt that any water is entering the cable jacket and running down 50 feet to the inside. Trust me, I really did diagnose this one and having the rain water emerge from the wiring opening, just above the headliner, is what happens. If you watch it on a stormy day at the marina you can watch it happening.
Note that the rain is running down from all of the openings in your double-spreader spar and emerges inside at the wiring access hole because it reached that point and followed the wire bundle inside. A surprising amount of water enters that spar, especially when any significant wind blows it at the side of the spar.

That said, one of the several failure points of old mast wiring is moisture slowly seeping/wicking into the cable and corroding the wire, over the years. Same with coax, sometimes. That's why it's good to replace the wiring and coax when you have the mast down for new standing rigging, every couple decades.

Also, we have what appears to be the same terminal block as Ken's boat.

 

[Kenneth K]

Herbert and Loren,

I'm not saying that what Loren describes in NOT happening on your boat, it could well be. I am saying that I definitely had wire coming through the INSIDE of the wiring jacket in this situation. In the pictures I posted in the link above, that is the reason I put two loops of paper towels OUTSIDE the wiring jacket. The paper towels on the OUTSIDE of the wire stayed dry, but water from INSIDE the jacket filled the cup.

I did not do the install on the steaming/deck combo light (mounted mid-mast) that this wire feeds. However, you'll see a lot of jacketed wire installations where the installer pulls/rips the inner wires out of the jacket rather than making a clean cut on the jacket. This creates a wider opening (like a funnel) where the wires enter the jacket near the installed light fixture--I believe this where the water is entering. Once water enters, it's not hard to imagine gravity forcing it downward through 25+ feet of vertical wire.

The real fix would be to seal the area where the wires enter the jacket (or, install a drip loop here), but this requires climbing the mast and removing/replacing the light fixture. I had this on my to-do list all last summer but never made it. In the mean time, I did make an embarrassingly temporary fix that has been holding well for nearly a year:


A drip loop external to the mast, with the outer jacket stripped off to allow the jacket to drain. A syringe-body taped to the mast with a small tube connected to the syringe nipple catches water from the drip loop. The tube drains into the bilge. After the "real" fix, I can tuck this wire back up into the headliner, out of view like it is supposed to be.

You really can't make this sh*# up!

 

[Kenneth K]

I believe this is the wiring hole in the mast Loren is referring to.



Obviously, it would be a likely culprit for leaks in this area. If you compare the scratch marks above (right about the 6' level on the tape) with the those on the previous photo, I think this hole is too high up in the mast partner (on my boat) to be accessible from below, for caulk/sealant, etc. If yours is similar, a leak from here would be tougher to address than a leak from inside the wiring jacket.

 

[Loren Beach]

That water catcher is clever. Learned something new today.

 

[HerbertFriedman]

thanks to you both, I will remove the teak trim boards and see if I can access the hole in the mast. If so, it looks like I have a date to be at the boat during the next hard rain to see if I can tell if the drip is coming from the wires themselves or from inside the white cover.

If the drip is from the wires themselves, then Loren's solution of gooping up the hole in the mast should work. If the drip is coming from the inside the white cover, then I might be able to slit the white cover enough to allow me to stuff the slit cover back inside the mast, but I doubt it. I dont like the idea of gooping up the wires inside the white cover because that traps moisture, probably not a wise rout.

Certainly the next time the mast is pulled I can re string a new wire bundle and make sure the white cover does not come through the hole in the mast. But that solution requires me to remove my stack pack, mainsail and boom plus $200/hr for the crane, uggh. I agree you cant make this sh*t up. Again thanks, I hope this dialogue was of help to others.

 

[Rivergirl7]

To revive an older thread, we are encountering the same issues, water drip down the inside of the mast, with some trailing the wires out above the headliner, as well as water inside the casing of wires coming down inside the mast. The exit hole in the mast is literally at the same height and location as the rubber boot spacer around the mast. The boot doesn’t go fully around the mast so to accommodate the wires that exit through that hole and then splay out across the cabin top, underneath the liner. A very difficult spot to work on. We will attempt the ‘syringe drainage system’ initially, I think. I’ve seen water coming out one of the casings on a slight uphill run., so that’s a given. And we have sealed the cover boot, still intact, up on deck with dreaded silicone and, yes, we monitor the mast base drainage limber hole to the bilge religiously. And we have rebedded the boom vang gooseneck, as well as the stainless plate on deck around the mast, but still get some water inside the cabin on the outside of the mast, though this is of lesser significance's at the moment because it drains into the molded depression the mast step sits in, which drains into the ‘shower’ bilge. If anybody's come up with additional insights, we’ll gladly listen. Thanks.
Jill & Steve
SV Whispering Swan
1986 32-3

 

[Kenneth K]

And we have rebedded the boom vang gooseneck, as well as the stainless plate on deck around the mast,

When you removed the stainless plate around the mast--was that through-bolted or or just fastened with screwed in from above?

I'm getting wet plywood around the mast opening and I'm thinking I may need to remove that plate too.

 

[Rivergirl7]

Just screwed in from the top with those big screws. If you drop that plywood piece, you’ll see the tips of the screws through the deck. A couple needed a little coaxing, but came up pretty easily. We are butyl tape fans, so that is what we used there and the boom vang gooseneck, and with a hose, checked our work, and seems secure. Our plywood has been wet before, but it’s currently laying on top of the liner while we track down mast leaks. Now I believe that water came from leaks on the outside of our mast, and that, I think, is the aluminum extrusion that was fitted to fill the sail track is not watertight. When we spray the mast below the boom, leaks outside the mast track, usually aft to port, has rivulets running. But nothing if it’s dry and we just wet the stainless plate. Did you have to pull your mast to fix the wiring leak? I just brought down syringes of all sizes ( nurse’s benefits ) to see if we can make the leak track to the bilge. And if THAT happens we’ll consider scarfing the top of that port bulkhead/dividing wall. I guess not technically a bulkhead because the way our stays are the wires than come into the salon instead of metal plates attached to formal bulkheads. Good luck, keep us posted?
Jill & Steve
SV Whispering Swan
1986 32-3

 

[Kenneth K]

Just screwed in from the top with those big screws. If you drop that plywood piece, you’ll see the tips of the screws through the deck. A couple needed a little coaxing, but came up pretty easily.

Good to know. I was wondering if I'd have to remove that plywood piece to get to the nuts if it was thru-bolted.

Did you have to pull your mast to fix the wiring leak?

I've neither pulled the mast nor "fixed" the wiring leak. The syringe "collector" is still faithfully doing its job!