Water system leak

Feb 14, 2023
1
Hunter 336 Grand Pappy point Marina
I have a hunter 336 . I failed to winterize the water system and have a leak in the water line. any sugestions on how to find the leak and maybe where to look first?
 
Jan 11, 2014
13,013
Sabre 362 113 Fair Haven, NY
Welcome to SBO.

Finding leaks can be challenging. Look for the lowest points in the system first and recognize you may have multiple leaks. The worst place to have leaks is at the tank fittings because they will be difficult to repair. It may be easier to simply replace all the plumbing as Murphy will predict the leaks will be in the most inaccessible places.

Good Luck. :beer:
 
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Likes: NYSail
Dec 2, 2003
764
Hunter 260 winnipeg, Manitoba
If you can drain any remaining water you might be able to pressurize the lines with low pressure air (somewhere around 25psi) using a compressor. You should then be able to hear the leak.

The one spot I would always check is right at the potable water pump - amazing how often they seem to either develop a leak or have a fitting that’s not quite tight!
 
Jan 19, 2010
12,593
Hobie 16 & Rhodes 22 Skeeter Charleston
If you can drain any remaining water you might be able to pressurize the lines with low pressure air (somewhere around 25psi) using a compressor. You should then be able to hear the leak.

The one spot I would always check is right at the potable water pump -
Yep!!! A freeze busted my galley pump once.
 

LloydB

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Jan 15, 2006
927
Macgregor 22 Silverton
If you're as deaf as I am trying to find the low air pressure leak by ear you could also take a bottle of bubbles and a paint brush and hit each junction in your water line to see where it is blowing bubbles.
 
Dec 14, 2003
1,433
Hunter 34 Lake of Two Mountains, QC, Can
You might want to fill the system with some food dye in the water. The now colored water will be easier to see and hopefully your leak will show up.
 

MitchM

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Jan 20, 2005
1,031
Nauticat 321 pilothouse 32 Erie PA
A lot of leaks occur where the pipe or hose bends 90 degrees, because there is increased friction as the incompressible liquid tries to pass at the bend. I ve seen a frozen radiator system in a couple of houses where the copper pipes actually burst only at the bends , making it a pretty easy diagnosis and fix. I d put paper towels below the water pump and at each bend, then throw some potable food colorant into the water tank . turn the pump on and watch for any colored drips onto the numerous paper towels.
 
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Likes: Parsons
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
Welcome to Sailboat Owners - hell of a way to start! Most probable places for freezing expansion leaks are hard joints and pumps, rather than flexible tubing that may just expand with the ice. It's also convenient as there are far fewer hard joints and they typically are not behind a bulkhead. The downside is that tubing is cheap and pumps are not.

Good tricks above. Another one is that kid's watercolor paints are always water soluble after drying. You can paint lines downhill of your water system (towards the bilge), let it dry, and running water will draw lines through the paint. It's not the answer, but it may help you find the direction and rule out whole areas that are not leaking.
 
Sep 24, 2018
3,438
Catalina 30 MKIII Chicago
If you don't like the idea of potentially dyeing something with food coloring, you can buy non-toxic dye tracer that glows under blacklight from most hardware stores or plumbing supply houses
 
Oct 26, 2008
6,295
Catalina 320 Barnegat, NJ
I'm assuming your boat is in the water over the winter on Lake Texoma? If that's the case, I have a hard time believing that you actually have damage from a freeze. But if you did have freeze damage, I can't imagine that you wouldn't be able to identify the leak simply by pressurizing the system. A freeze damage would usually be enough to find water literally spraying out. But you haven't described any symptoms. The simple answer is look where it's wet! It's normally pretty easy to find. Don't forget to look at your transom shower fitting, if you have one. That's a common location for leaks.

I typically find problems at the fittings where the lines come together from 2 tanks in front of the pressure pump. I've been able to reconnect lines to stop leakage only to find it re-occurring months later. :facepalm: The other location is at pressurized fittings right after the pump. There is a slight difference between 1/2" PEX tubing and very similar 15 mm PEX tubing and people have mixed and matched those fitting components incorrectly, which can also lead to leakage that isn't apparent at first.