Colored dye to trace a water leak ?

T

TJM

Member
Member
Joined
Jan 1, 2000
RO Number
2909
Messages
498
After a few weeks away from the docks on vacation I have confirmed that I do have a fresh water system leak "somewhere". I have three tanks ( 40, 50 and 60 Gallons ). I am loosing substancial water somewhere, they are not isolated from each other with valves, they are daisy chained together, Ugh.

I am positive that the failure is not on the pressurized side after the pump.
Of course they are steel - foamed into the bowels of the hull.
I remember a dye that was discussed to place in the tanks to aid in tracing any leaks.
Being a 30 yr old boat, my bilge has small amounts of water with many bilge pumps to evacuate all water.
 
How will die help since all the pressure lines come from same pump?

Run your hand along the lines. If anything was worked on start there
 
I'm assuming you want to determine which tank is losing water. I had a problem finding a leak in my 2465 Regal and used food coloring to determine the source. It works really well.

The only drawback I can see is if there is more than one leak.

FWIW, I used primary colors that when blended would make a secondary color. That allowed me to find out if the leak was either, or, or both.

As to the pumps, pull the fuses.

Good luck.
 
Don't use food coloring. Next time you wash up you may be a redneck or have an urge to open a casino.
Just fill 1 tank with vodka, 1 with bourbon and 1 with rum . Since the tanks are daisy-chained this won't help a bit but if you keep test-tasting the "water" you won't care about the leak for long.

Are the tanks hard-plumbed together or with hoses and is the daisy-chain(presumably at the tank bottoms) accessible or foamed in as well? Just 1 fill hose for all? Could you you rig a pressure or vac test on each tank?

Are all 3 in the same foamed-in compartment or are there mini-bulkhead separators. If by any chance the latter , could you "drill" , maybe hand turning a long bit , down through the foam to tank bottom level and use a clear vinyl hose as a straw to see if localized water can be drawn up, or use water-indicating paste like Sar-Gel or Kolor-Kut on the end of a thin stick?
 
Let me add some more info.
Tanks 2-3 are plumbed together using clear tygon tubing on the bottom of the tanks, both of the welded fittings into the tanks are visible on three sides (not the bottom).
Tanks can be filled from either of the three deck fills on top of the deck so there are no check valves between any tanks to prevent cross contamination. So the 'drink mix" theory would be fun but the cocktails would all be the same, lol

The leaks are on the non-pressurized side of the pump. When we are on pressurized dock water, we have no issue with a cycling pump or any leaks in the bilge.

Occassionally we get a hint of dirty "rusty" water when using the water from the tanks, leading me to suspect a breach in a welded fitting in the tanks. Yes, the tanks are stainless steel (?), but from a 1981 taiwanese trawler where I am sure they were not passivated or made from 316L.
 
"When we are on pressurized dock water, we have no issue with a cycling pump or any leaks in the bilge."
When you are on pressurized dock water the pump wouldn't turn on anyway.

It almost sounds like you could be intimating the pump ...does... cycle when on tank water(w/spigots closed). But that must not be the case since you have said repeatedly the issue is not on the pressurized side of the pump so it shouldn't be cycling without the demand if the leak is before the pump.
 
TJM said "The leaks are on the non-pressurized side of the pump. When we are on pressurized dock water, we have no issue with a cycling pump or any leaks in the bilge."

If the leak is before the pump it would leak all the time. Are you sure your pump isn't cycling when on the tanks? Could there possibility be a check valve alter the pump prevent dockside water pressure on the pump(I have one on mine). I have a feeling you may be looking in the wrong place.
 
quote:
Originally posted by Ron Dudas

TJM said "The leaks are on the non-pressurized side of the pump. When we are on pressurized dock water, we have no issue with a cycling pump or any leaks in the bilge."

If the leak is before the pump it would leak all the time. Are you sure your pump isn't cycling when on the tanks? Could there possibility be a check valve alter the pump prevent dockside water pressure on the pump(I have one on mine). I have a feeling you may be looking in the wrong place.

Click to expand...


Beat me to it.
 
Can you add a valve in between the tanks?
This would allow you to isolate the leak.
If you don't need the 3 tank capacity, you could
bypass the bad tank, once you isolate it.

On mine I added a T with three valves one on each side of the T.
On the odd side of the T, I have a hose fitting flushing/filling.
 
What I meant to say was .......
We have no issue when pressurized dock water is applied to the boat and we do not have a cycling pump when at anchor when we are using the tank water.
Valves or "shut offs" between the tanks would be nearly impossible. Each tank is sitting on the hull with foamed in sides close to bulkhead panels. The tanks are connected in series and are gravity fed to each other.
Once I find the culprit tank or fitting construction will begin, hence the question of the colored dye.
I may just remove all of the tanks and replace them with custom welded plastic tanks. That would require some serious repair on my floors. Making the tanks would be the easy part.
Is the food dye really a problem ??
 
Blue in the first one, yellow in the second. I can see little downside. It may not work, but then again, food coloring is cheap. Hunting can get expensive.
 
I don't think anyone thought dye was a problem, but maybe wondering both how you will introduce it to just one isolated tank per color , and if it mixes into all 3 tanks how you will determine where it came from if it makes it into the bilge. You have a much better image of how you would go about that on your boat than we do.

If you do end up deciding it's time to replace, I think you will like the poly tanks. There are a lot of sizes available in 40, 50 & 60 gal capacity, so maybe ? you could find usable prefabs. Here's just one of the suppliers: http://www.plastic-mart.com/category/30/marine-water-tanks
 
if there is access to put different colored dye in each tank, then putting a temp plug inside the tanks connecting tubes should be possible. there are devices made specifically for this in plumbing supply house. its a small tube of varying diameter that has a small hose w Schrader valve to inflate after its placed inside the tube.

this would allow the tanks to be isolated and filled with colored water. it would also identify if the tanks or the connecting lines are the source of the leak.

I am questioning the source after reading thru the posts. if there is no leak when the pump is turned off, ie dockside water supply. I am thinking this is not a water tank leak but rather a pump fitting leak. to validate this, plugging the vent line and slightly pressurizing the tank (2-3psi) chain will work.
 
You must log in or register to reply here.
Back
Top