My quest to stop deck leaks

sailnc

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Sep 6, 2014
30
Hunter 37C New Bern, NC
Greetings from New Bern, fellow Cherubinians!

I’ve been making slow but steady progress in my quest to eliminate deck leaks on our 37C. I've tightened all of the toerail bolts, rebedded the chainplates, and replaced gaskets and lenses in the portlights, and this has helped significantly. I no longer have to leave an array of pots and pans to catch drips when we are away from the boat.

The remaining leaks are more sneaky. For example, a bit of water comes in behind the breaker panel. It gets there via a hole in the ceiling where some wiring is run (to cabin lights etc.), so water must be entering via the cabinhouse deck. It also drips through the aft cabin ceiling light fixture. Some candidates, based on my reading here, would be the companionway cover or the teak grab rails. Rainwater is likely entering one of those areas and following the cabin ceiling to its escape route.

So where exactly is the leak-prone area of the companionway cover? Is it in the track on which the plexiglass slider moves? Or the fixed fiberglass hood that goes over it? If I remove the spray hood will it be pretty obvious?

Another minor leak source is the small Bomar overhead hatch over the galley. I think this is simply needing new gasket material… it appears to be a foam rod maybe around 1/2” diameter (hard to tell, as it is deteriorated). Any thoughts on finding replacement?

As always, thanks for your help and motivation!
Tom
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
No experience with your particular model, but ours had leaks under the traveler supports. I had to use an impact driver to loosen the screws, then used butyl tape to seal it. Our job tracks also leaked, it was the same story. We also had leaking jib tracks. On each of these, there is an aluminum piece buried in the fiberglass that the screws thread into. Once again an impact screwdriver to break them loose, then I used a cordless drill to remove the (seemed like thousands of them) screws. I had to use a tap to clean up the threads before resetting the screws. I also used anti-seize to reduce galling due to stainless screws threading into aluminum. I also used a countersink to enlarge the pocket for sealant.

Here is a link that Main Sail was kind enough to post for us. He's right on this.
https://marinehowto.com/bed-it-tape/

Ken
 
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Likes: kloudie1
Jun 8, 2004
994
C&C Frigate 36 St. Margarets Bay, Nova Scotia
You are certainly nailing the major sources. The dorade boxes are a known source, as is the wood surround around the companionway (where you slide the weather boards in). If you have a later H37C with the traveler on the cabin top, I would also suspect that. The chainplates and the ports (where bedded in the cabin sides) are a major source of leaks, but it sounds like you are on those. And anywhere a screw penetrates the deck - handrails, eyebrow trim, mast partners, etc. - is suspect.
 
May 27, 2004
1,964
Hunter 30_74-83 Ponce Inlet FL
Not sure of the term "Rod", but if your hatch is like my Bomar hatches, the foam wx stripping/gasket is available here at the SBO store.
 
May 31, 2007
758
Hunter 37 cutter Blind River
My quarter berth cabin light would also flood after a good rain. Was worse when the dodger wasn't installed. Then I removed the handrails for refinishing, inserted teak plugs in the screw holes before varnishing then reinstalled with screws from beneath, through the liner. So far, after three seasons, no more aft cabin light leak!
 

sailnc

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Sep 6, 2014
30
Hunter 37C New Bern, NC
Very interesting- thanks!
I haven’t tackled those handrails yet. Just looking at them it is hard to imagine how any water would be getting in through them. But I can’t argue with actual experience! So
I’ll take a closer look on next visit. Did you have to drill out the bungs to get access to the mounting screws? Are they just screwed in with wood screws or are there backing washers and nuts?
 
May 31, 2007
758
Hunter 37 cutter Blind River
The original screw holes from the top now have teak bungs epoxied in. I removed the original bungs with a 3/8" forstener bit to access the mounting screws. After refinishing, I refastened from below. Using the existing screw holes, I first drilled through the deck straight down through the liner for the shank size of the new screws. I then drilled up through the liner if memory serves a 3/8" hole, big enough for the screw head and a washer to pass. These holes were later covered by plastic plugs (which will determine the liner hole size) that the local chandelry ordered for me from their primary distributer. It took two to complete the install - one driving the screws from below and one on deck aligning the screws with the holes in the base of the rails. It was certainly far less messy using butyl tape for this process than 4200 or similar.
 

Spazz

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Oct 9, 2016
11
Hunter 1978 cherubini 30 shoal draft Little Falls
We are having the same problem with leaks behind our electrical box. Discovered the it was coming from the job tracks. We actually decided to remove them all together; epoxy the holes, and apply non skid over the top. I have a 1978 and their is no way to run the sheets on the outside of the shroud if you have more than a 100% (Which we do), So why have the tracks anymore; plus removing them adds more deck room.

I am curious if anyone can explain to me what you mean by "reseat". I am new to sailboat maintenance and do not want to learn this one the hard way. I have to reseat my stanchions and my chain plates. I haven't noticed any leaking from the toe rails (and can only imagine how time consuming of a job that is).
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
I used food coloring to color 5 gallons of water in a bucket. Put a white towel in the area of the leak. Slowly poured some colored water on the suspect source and waited for 30 minutes. No color stain. Move to next spot.

I found 100% of all my sources.:clap:

Fixing them was easier then.:)
______
I am curious if anyone can explain to me what you mean by "reseat"
I had to lossen my stanchions, Put in the butyl rubber and the tighten them down again or "reseat" the sealing. I made sure NOT to remove my screws, since it is much easier to "reseal" them since they have backer plates.

Jim...
 

sailnc

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Sep 6, 2014
30
Hunter 37C New Bern, NC
:plus:For the colored water idea. Gonna try that myself for my remaining mystery leaks.