Mystery leak

Jan 11, 2004
65
Hunter 31_83-87 Middle River, MD
Found wet fabric at the very aft end of the quarter berth (1986 H31). This is usually a dark, damp area with no ventilation, but the water was very noticeable when I peeled up the fabric. I checked the port side cockpit drain hose that exits in this area, but found no leaks. I have checked all around this area, but nothing jumps out as the culprit. Any ideas or similar issues?
 

SFS

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Aug 18, 2015
2,066
Currently Boatless Okinawa
Some ideas:

1) Water can come through cockpit scupper fittings. It drips to the quarterberth surfaces, then migrates to the lowest point, which on my 1983 H31 is the aftmost point of the quarterberth, along the transom at the centerline bulkhead.

2) If the scupper fitting leaks, it can drip onto the top of the false ceiling above the quarterberth and migrate across the boat, down the centerline bulkhead, and ending up in some strange places.

3) The floor of your aft cockpit lazarette likely has one or more hoses coming through it (vents, fills, etc). If water gets in the laz, it just comes through the floor, and ends up in more strange places.

One thing to remember. Leaks can occur a LONG way from where you see the water end up. And water will run uphill, which seemingly contravenes the laws of physics.

Try these threads, which elaborate on those three ideas. The second one is long, but covers a lot of possibilities:
https://forums.sailboatowners.com/index.php?threads/surprise-my-boat-leaks.179496/&highlight=leak

https://forums.sailboatowners.com/i...nt-leak-near-fuel-tank.181234/&highlight=leak
 
Last edited:
Jan 11, 2004
65
Hunter 31_83-87 Middle River, MD
SFS, thanks very much for your help. I have seen water in the lazarette at various times, so I will need to check out that area for potential leak sources.
 

SFS

.
Aug 18, 2015
2,066
Currently Boatless Okinawa
You are most welcome.

On my boat, the water that gets into the aft laz comes thru that laz floor, down the hoses, and ends up in at least two places: a) that deepest pit under the starboard laz (which I call the basement) just aft of the battery tray, and b) the place where you are encountering dampness. The water drips off the hoses onto that centerline bulkhead and runs aft, on both sides of, and under, that bulkhead.

I plan to caulk the hole where the hoses run through the laz floor, but I need to stop water from getting in that laz in the first place. The entry point still puzzles me.
 

Reg M

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May 21, 2016
131
Hunter 31 Montague
SFS - One common way for water to get into the aft laz is under the edges of the aft laz covers when you are hoseing down the cockpit. The lids rest on those rubber bumpers which are about 3/4 of an inch high.
 

SFS

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Aug 18, 2015
2,066
Currently Boatless Okinawa
Reg, good to hear from you. I am aware of that mechanism of entry, and guard against it as best I can. Our problem seems to also include wind-driven rain from precisely the right direction. I am currently thinking about options for a) increasing the height of those "lips" on the laz, and b) sealing the hole in the aft laz floor through which the various hoses run.
 

Reg M

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May 21, 2016
131
Hunter 31 Montague
Steve
You might try some of that thick weatherstripping and stick it to the bottom of the lids between the rubber bumpers. Sorry I did not get to take you up on your sailing offer last winter but due to my Mom's illness we did not get down to Florida until late Dec and then came home mid Apr. The winter just seemed to fly by. Regards
Reg
 

SFS

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Aug 18, 2015
2,066
Currently Boatless Okinawa
Reg, it's a standing offer, though we are getting closer to taking a stab at full time cruising. Sold the last piece of real estate yesterday, and are back to prepping the boat.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Mine water comes through the deck-hull joint from inside the rubrail. Flows down transom locker and finds its way to rear bulkhead (soaking and damaging the veneer) and wet the beddings. Tried Capt Tolley and Sikaflex but only reduces water intrusion, not stopping it. I suppose the rubrail has to come off to fix this. Thats gonna be quite some tough job. :(
 

mr c

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Aug 4, 2010
77
hunter sailboat 31 northport
My leak was from the glassed in tube for the cockpit drains on the bottom of the hull. Half way up the glassed in tube was a hole. Every time the boat bounced water would come in. Took awhile to find that.
 

abinkc

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Sep 29, 2008
21
Hunter 30T Grand Lake
I have a 1991 30T. Water is leaking in so bad on the back wall that I'm getting black mold. Replace the original panel as it was delaminated when I bought the boat. Now the new wall is black from the water leak. Of course, I've removed the mattress and the wood panels. I've resealed the bottom of the pedestal, but that back wall is still wet. The port lazaret does get rain water in it but it drains out the drain hold. I see no solution except to removed the entire rear wall for a close examination of the fuel tank area. Any advice.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Another leak source would be from cockpit mounting screws. These usually penetrate to rear berth or transom storage area below. Leak could travel to rear bulkhead and down to cushion/beddings. That how my rear berth got wet...apart from rubrail/deck-hull joint leaks. So I sealed the screw holes and use plastic steel epoxy to mount the stuff instead.
No more wet berth no more wet beddings.

Ken Y
 
Jun 8, 2004
10,024
-na -NA Anywhere USA
Try pressuring the cabin by closing off everything and then tape a singl piece of plastic over the companionway. Put slit into plastic and slide leaf blower into slit tapping that too and turn it on. Someone with a brush and soapy water brush everything topsides looking for air bubbles should find topside leaks. An old marine yard trick to pressurize the cabin with air trying to escape
 
Jan 24, 2017
666
Hunter 34 Toms River Nj
I had an annoying leak in that area on my h34 which I found from my binical guard and my pedistal bolts.
 
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
Try pressuring the cabin by closing off everything and then tape a singl piece of plastic over the companionway. Put slit into plastic and slide leaf blower into slit tapping that too and turn it on. Someone with a brush and soapy water brush everything topsides looking for air bubbles should find topside leaks. An old marine yard trick to pressurize the cabin with air trying to escape
I actually watched a friend of mine do this with a shop vac, on his 34 footer sailboat. After spraying water and some soapy solution all over the cabin and deck he did indeed find some bubbles emerging from some fittings that he never suspected. Quite a bit of tape was applied around seats, hatches, vents, and etc. He roughed out a replacement hatch board with with a 3" hole for the vac hose.
:cool: