Persistent Fresh Water Leak

[Tim2022]

Hello,

I have an intermittent fresh water leak. It is detected by my bilge pump cycle counter. Sometimes the bilge pump will cycle up to 6 times per day and other times it will go for weeks without coming on. The issue only happens when the fresh water pump breaker is on. The pump is a 5pm jabsco pressure activated pump and my hose is connected with barb fittings and heavy duty hose clamps. The hot water tanks a new Isotemp 11. I’ve inspected all the connections I can find and have not found any with signs of leakage.

Can anyone suggest a method of tracking down this leaks ?

Any advice on this would be much appreciated.

thank you,

 

[dlochner]

We have spent the past year tracking down similar leaks and have found multiple leaks. Some things we have tried:

Look for damp areas that shouldn't be damp. Once identified, look for subtle signs, rusted hose clamp, hardened hose, discoloration.

With the system under pressure, wiggle and move suspect areas. Sometimes that will expose the leak. One leak we found was not visible until he hose was move and water sprayed out of a pinhole leak in the hose.

Try to identify whether the leak is on the hot water or cold water side. Pressurize the system, turn off the pump, and wait. Preferably over night. If the leak is on the HW side when the HW faucet is turned on there will be less pressure than on the cold water side.

Tighten all clamps. Over time they loosen due to compression of the hose walls and gremlins.

Be prepared to do a lot of boat yoga searching in hard to reach places.

 

[rgranger]

If you have more than one tank or water source, you can try putting different food color in each and hope to see what color you find in the bilge. That would cut your search in half if you find something.

 

[Johnb]

Never used it myself, but a buddy has employed the food dye method a bunch.

It could also be a slow intermittent leak back through the water pressure pump caused by wear or detritus in the valves.

 

[Leeward Rail]

This dye suggestion made me curious.

Having used UV dye for detecting refrigerant leaks, I wondered if there were edible fluorescent food dyes...
.. There is!

Here is one example:

Colourings

www.sosa.cat

 

[dlochner]

Just what I want in my morning coffee, DayGlo Orange! Yummy!

This isn't really hard, searching for the leak is just about going where no person has gone before, or at least since the boat was built.

 

[Leeward Rail]

Just what I want in my morning coffee, DayGlo Orange! Yum

All the hip kids do it with their hard liquor.

Besides, it is likely just Riboflavin aka Vitamin B2, which is very fluorescent.
Evidently, if you body doesn't need it, you just end up with: Glowpee

Easy enough to drain the tank and refill later.

 

[Johnb]

This dye suggestion made me curious.

Having used UV dye for detecting refrigerant leaks, I wondered if there were edible fluorescent food dyes...
.. There is!

Here is one example:

Colourings

www.sosa.cat

No way going to use their brown dye.

 

[capta]

I would suggest using a pressure pump just like they do on auto radiators. Also, you could connect a hose from shore water. Standard boat water pressure is around 30# whereas household is closer to 60#. You might make some new leaks, but you will also find older ones.

 

[BarryL]

Hi,

Put some paper towels under as many hoses, connectors, pumps, etc. as you can find. Come back a day later and see which are wet and which are dry.

Barry

 

[thinwater]

The OP never said if he checked whether the tank level is going down (if there is enough to trigger the sump it should be).

It is possible it is rain water and the occurrence is coincidental.

He did not say if there is an accumulator tank. If not, I would add one. skipping the tank is just poor design, because a hot water heater (expansion) can easily make the pressure go OVER the pressure set point, causing leaks. Such a system would not me code on dry land.

 

[Ralph Johnstone]

Sometimes the bilge pump will cycle up to 6 times per day

You have one hell of a large leak with that amount of water being discharged from the bilge. Problem is, you've not yet come across the leak because it would be seen as a large, continuous flow of water.

Additionally, pressurize the water distribution system, shut off the Jabsco water pump, and see how fast the system pressure drops. Shut the pump suction valve if there is one. If you don't have a pressure gauge in the system, install one. No one said this was going to be easy.

Good luck and let us know what turns up.

 

[Tim2022]

Thanks for all the input. This is extremely helpful and very much appreciated! I don’t have an accumulator tank and don’t see it happening as a result of rainfall. It is random and unpredictable. The only association I can draw is that it only happens when the fresh water system is pressurized. But even when pressurized it may go for weeks without any bilge pumping and then for no apparent reason starts cycling several times a day. It’s not a false reading on the bilge pump counter as we can observe the water being discharged. I like the suggestion of over pressurizing the system “a little” with a dock hose. Also the pressure gauge idea could work. It’s a 47’ Catalina with a lot of concealed hoses but I thought I could zone off areas with valves and pressure gauges for each zone to hopefully isolate the problem. I also
think the “hose clamp wiggling” could yield results. I’ve have used the paper towels and will continue with that but the wiggling may uncover something that is intermittent. The boat is moored in a river 6 miles upstream from the ocean so surrounding water is relatively fresh so tasting for salt is not a reliable indicator. But given that it only happens with the water pressure on, indicates it must be an fresh water plumbing leak.

I’m new to this form and amazed at how helpful people are here. Thanks again!

 

[Ralph Johnstone]

I like the suggestion of over pressurizing the system “a little” with a dock hose.

Not a good idea at the best of times. Check on the pressure rating of your new hot water tank and ensure it will be able to with stand any dock pressure supplied. In addition, check the dock pressure and see if they are using a pressure reducing valve or giving you full pressure from your utility supplier.

The reason I say not a good idea is because increasing the pressure is not going to make the leak magically appear. It may start other leaks. It's there, you know it by the flow rate you've reported:

Sometimes the bilge pump will cycle up to 6 times per day

It's a big leak, not a slow dripper. You just haven't found it yet.

 

[dlochner]

When the hot water tank is hot, it increases the pressure on the HW lines because the water expands. This pressure increase can cause fittings to leak. The pressure is greater when the tank is heated form the engine as the water temp will be approximately the same temp as the engine's operating temp. Higher temp equals higher pressure.

If a check valve is not installed on the HW tank inlet, the pressure from heated water will go out both the inlet and outlets.

Finally, hot water can soften the hoses a bit which may allow more leaks.

 

[FastOlson]

Speaking of "hoses".... if you have any remaining hoses in the system(s) that are over 20 years old and are not yet cracking or swelling, replace them anyway. These products do have a design life.

 

[Tally Ho]

Have you ruled out the stuffing box as a source of water?

My O’Day 322 only has water in the bilge now when it rains(and I can’t find where it is coming in from) now that I went to a Volvo dripless stuffing box.

I would think your water tank would be empty pretty quickly if the bilge pump is cycling 6 times a day. Are you noticing it going down ?

Greg

 

[Davidasailor26]

I would think your water tank would be empty pretty quickly if the bilge pump is cycling 6 times a day. Are you noticing it going down ?

I’d also expect to hear the pressure pump cycling a lot. That would be a pretty good tell of whether the water is coming from the pressure side of the fresh water system or not.

 

[dmdiehl64]

Do you have a heat / AC system installed? Our bilge pump would cycle a few times a day and it had me boggled. Turns out the condensate tray from the coils led to a hose which went down into the bilge. Just enough "intentional" water to cause the bilge to pump out a few times a day.

 

[Mike8193]

I had a leak on my boat when I purchased it new in 2005. Water would accumulate only when the fresh water pump was on. The system would pressure up and the pump stop but water accumulate. Manufacture reps tried hard to find it and couldn't. One day I laid down in the aft cabin and watched the water accumulate. I then went in the starboard locker and climbed as far back as I could and found the leak, it was coming from the swim platform hand shower. The hose to the hand shower was loose and just needed to be tightened up. It stopped the leak. It was slow enough that it let the system pressure but large enough that water would accumulate. It was in a remote awkward position, to find it was difficult. Hope you find your leak. Please let us know when you solve it.