water in encapsulated keel...

this boat was built with a bulb keel shell, lead ingots down in the bulb and concrete over past the turn of the bilge...sort of a wine-glass shaped plug. as the boat sat for many years, rain water made its way to the bilge and seeped past the concrete and into the bulb separating the fiberglass shell from the concrete. ive drilled some holes and determined the gap to be no more than 1/8". may plan forward is this :

1) air dry with sun on the keel then fill the gap with acetone or alcohol and drain. repeat. and maybe repeat again.

2) fill the gap with low-vis, slow-cure epoxy with some fibers.

3) glass over the bulge to permanently (?) seal out future ingress.

any problems with acetone and polyester? any problems in general ?

thanks again...

 

You might put a vacume pump on the keel and suck the water out.

Best would be to cut a hole , empty the ballast then re ballast.

Obviously you must fix the leak that causes this.



What the story with that bulge on the leading edge ?

 

You can also pour acetone (Better than alcohol) into keel to help draw out the water. Let it sit for a few weeks to dry everything out. Concrete will take a long time to dry out, the more you remove the better off you are. Vacuum pump is a good idea.

 

The problem will these "remedies" is they don't address the two major concerns; first is there laminate delamination from water freezing and thawing repeatedly, within it and how are you going to clean the bond areas between the ballast, concrete and hull shell.

You can hope to get lucky with the laminate and the epoxy pour might help firm things back up, but for this to happen you need a clean, well abated surface for the epoxy to grab or you're just adding another material to the mix of problems in your bilge. Epoxy will not stick to laminate, concrete and lead if they've been stewing in stagnant water for a while. An acetone wash without a scrub isn't going to do much, except sterilize the still contaminated surface.

At the very least consider widening the top of the gap, so you can clean the upper portion of laminate and concrete. This way you'll know the very top few inches are well bonded to the hull shell and concrete.

 

What Par says is true, best thing would be remove everything. Or you can just fix it for now and worry about the rest later.

 

there are low visc epoxies that will bond to wet or damp surfaces, such as "Low V" epoxy. It is often used in rebonding delaminated deck cores etc. You certainly want a solvent free epoxy - no solvent outgassing in confined spaces please!

Bigger voids commonly filled with similar moisture tolerant epoxies mixed with sand (often used for pier/piling repairs) too.

paul
progressive epoxy polymers inc

 

I have removed the water successfully by cutting several holes on the sides of the keel with a holesaw. You can later laminate patches and pour resin from the top to fill the gaps.

 

I was thinking along those line as I typed, Paul, but then also thought of the biological coating that also must be there, if the water has had some duration within the confines of that hull shell.

Pictures would be helpful, but I've seen issues like this before and the usual course is to insure at least some of the concrete/hull shell interface is well bonded. This typically means chipping out several inches around the top of the concrete pour, grinding both the casting and hull shell, filling the lower void as best as you can, then topping it off with a reinforced mixture (milled fibers and silica), that really seals the area. With some luck, very little trapped moisture will remain and the well sealed upper portion will prevent future issues.

A few well placed holes in the hull shell is a good idea sometimes, depending on how much moisture we're talking about.