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bdbFC
08-13-2016, 08:27 AM
I've been scratching my head over this one.

In the deepest part of the bilge, I have a slow leak somewhere (probably from the garboard, I think) that will add about a quart of water over the span of about a week. However, once it reaches that level (roughly an inch deep in the lowest bay), it will stop coming in and then skim over with a funk if I leave it. It never reaches the level that the bilge pump will kick in. If I sponge it out, over the next week or so, it will fill back to the same level. No big deal, but it's annoying. When I haul out again, checking the caulking will probably take care of it.

BUT - the weird part is this is about 2 feet below waterline. I don't get it. Why is the inflow stopping?? Shouldn't it continue unabated until the boat is a submarine? What am I missing? I've triple checked to make sure it's not just back flow from the bilge pumps which was my first thought - even removing them altogether as a test. It's definitely not that. I'd love to hear ideas of what could explain this.

rgthom
08-13-2016, 09:36 AM
Is the bilge open enough that it could be evaporating to the outside? If the surface area of the water is large enough a quart per week of evaporation is sure possible. Evap rate also increases with higher temp and lower humidity.


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wizbang 13
08-13-2016, 10:28 AM
Spilled beer?

Raven12
08-13-2016, 01:32 PM
The surface area of the newly formed "pool" is sufficient to equal the force of the water coming in(?)

auscruisertom
08-13-2016, 05:45 PM
Are you sure it is not dripping though your stuffing box gland?

Phil Y
08-13-2016, 06:00 PM
I think your neighbor is sneaking aboard and putting some water in your bilge just to mess with your head.

bdbFC
08-17-2016, 07:33 AM
I don't think that evaporation is a factor as it's always pretty cool here with moderate humidity from the fog. And it is possible it's leaking in through the stuffing box and not from the garboard, although it seems like it's coming from below the bilge and not above it. It's such a small inflow, I can't see where it comes from, but in either case, the fact that it stops is still puzzling. Crazy neighbor is a possibility, but unlikely. I'm absolutely positive it's not beer, as I would never allow that travesty to occur.

I'll keep searching.

WoodyHuscarl
08-17-2016, 10:29 AM
Could be that the weight of the water in the bilge is closing the leak. Kinda like a finger in a dike. Does it leak more while you are in motion?

Rapelapente
08-18-2016, 02:23 AM
Did you taste the water ? To be sure it's not fresh water coming from a tank or condensation, or any deck leak?

Redeye
08-18-2016, 07:52 AM
It's obvious what's happening. There are two holes, the water flows in through the bottom one, and when it reaches the top one it flows out again.....

WoodyHuscarl
08-18-2016, 09:12 AM
One more thought, could it be that when the leaked water reaches depth X, it swells a board juuuust enough to close the leak? Might want to try the famed sawdust trick.

Canoez
08-18-2016, 09:30 AM
I've been scratching my head over this one.

In the deepest part of the bilge, I have a slow leak somewhere (probably from the garboard, I think) that will add about a quart of water over the span of about a week. However, once it reaches that level (roughly an inch deep in the lowest bay), it will stop coming in and then skim over with a funk if I leave it. It never reaches the level that the bilge pump will kick in. If I sponge it out, over the next week or so, it will fill back to the same level. No big deal, but it's annoying. When I haul out again, checking the caulking will probably take care of it.

BUT - the weird part is this is about 2 feet below waterline. I don't get it. Why is the inflow stopping?? Shouldn't it continue unabated until the boat is a submarine? What am I missing? I've triple checked to make sure it's not just back flow from the bilge pumps which was my first thought - even removing them altogether as a test. It's definitely not that. I'd love to hear ideas of what could explain this.

Condensation on the inside of the hull accumulating in the bilge?

bdbFC
08-24-2016, 01:51 PM
One more thought, could it be that when the leaked water reaches depth X, it swells a board juuuust enough to close the leak? Might want to try the famed sawdust trick.

I wonder if it's this. I'm sure it's not condensation or fresh water. But I guess it would make sense if a tiny hole is squeezed in some way when the pressure of the water in the bilge reaches a certain amount. It just seems to me that the pressure outside the boat would still be greater since it's below waterline, but clearly some equilibrium is occurring.

David G
08-24-2016, 01:57 PM
I think your neighbor is sneaking aboard and putting some water in your bilge just to mess with your head.

Spoken with the sure, concise, clarity of one who is quite familiar with this stunt... <G>

breaker
08-25-2016, 12:08 AM
do you have a fresh water tank ? I'm thinking that if the tank is topped off and the weather warms up the water expands a bit and vents out.??? Plumbing leak from galley or head?

Don MacLeod
08-25-2016, 06:09 AM
Bail it out so the bilge is dry.
Then take the boat for a sail in a brisk wind, full sail up, hard on the wind.
And go down below on both tacks and check the garboard plank joins.
The aim is to strain the boat as hard as you can and hopefully that will open up the weakness and make the leak very obvious.