Wet cored hull?

[maineguides]

I'm looking at a boat that had a survey in 2010. The survey stated that the rear spray rails had been ripped off and the screw holes had allowed water in the core (balsa. H&H Built in 1994). Moister content was higher below the water line than above. I'm guessing this is a big problem. Or is it?
Is there a fix? Any thoughts or advice would be greatly appreciated?

 

[F/V First Team]

Can you get to it? If so slice the inner skin, yank it off, tear out the core, prep the area and re-bed new core in the void, glass over, enjoy a cold frosty beverage of your choice.

 

[jerseysportfisher]

one of the problems with the cored boat in the north and water intrusion is the freeze. water freeze turns to ice, expands, delaminates. Once it delamininates the panel looses its strength. Another problem, is rot if it has got that far. gravity, is why you will find more water lower in the hull, and balsa does a good job of moving water. is there a fix yes, but this is a job you will want to pay someone to do. So factoring that in, the boat should be quite cheap on purchase.

 

[Dr Dude]

wet cored hull

I'm going through this now.
I bought a 30 yr old beauty that I had seen in the water. I had a survey, engine check, two test runs and bought the boat. I was there for the survey and watched as the surveyor banged all over the hull with his hammer just as it was lifted out of the water. I live 800 miles away and had the yard haul and cover the boat and launch in the spring. It was in the water when I saw it again.
To cut to the chase I never saw the boat on the hard but took the word of the surveyor that he found no moisture in the hull.
I had the boat hauled last week and after a few days I went to putz with it and noticed a wet spot on the bottom of the hull where a thru hull had been removed and the area patched with some kind of epoxy (maybe they used Bondo---I hope I'm kidding) when a new engine was put in 15 yrs ago.
A moisture meter was used and it showed a good amount of saturation.
This hull has Airex coring and we are using a gasoline powered vacuum over a ground out portion of the outer hull. This will be done for a few days and left open to hopefully drain and dry. In the spring (when it's warm) it will be filled and repaired and hopefully good as it can be.
There is a ton of info on this problem but it can be "fixed". Hopefully, in your case, it will go smoothly and quickly (and not deplete your bankroll).
Good luck with your project.

 

[Downeaster]

I'd categorize it as a big problem. In my opinion, it would be a very unusual downeaster to warrant the expense of correctly righting this if the soaked core was anything more than localized. Whether it is insurable is another issue to think about. I'd recommend your moving on.

 

[maineguides]

Thanks for the replies. I'm going to call the boat yard that does the work on this boat to see if they dealt with the problem or if it was covered up. Ill let you know what I find out

 

[captainlarry84]

Both First Team & Jerseysportfisher gave very good assessments. Water in coring is always a problem. Fordecks, hardtop & gunnels are all easy repairs. The hull is another story.
The job should be done from the inside as stated by 1st Team. Most likely it would require deck & fuel tank remove to cut the inner skin. A very invasive repair. Once opened up you need to remove all damaged coring which could take you well into the keel as the water will seek the lowest level.
Next was there a freeze which could have damaged the glass layup of the outer skin. If that is the case you may want to walk away.

 

[maineguides]

This boat sits in the water year round. Only comes out in the spring for maintaince In the survey the hull doesn't have any signs of delamination.
I was thinking that if its in the water all winter than it's never had a chance to freeze. I worry if I put it in my yard his winter it could freeze. Ughhhhh

 

[F/V First Team]

Couple of ways to deal with that,
1: a heater
2: yank them open from the outside and shove some antifreeze solution down into the core with a syringe
3: yank the inner layer off of the affected area &/or cut some holes on the exterior skin so that any moisture can migrate out, just be careful not to poke a hole through into the interior skin/fuel tank/holding tank/etc

Just because it's winter time and water tends to get hard doesn't mean that the moisture within the core won't leave, don't your lips get chapped during the winter months? That is because the air is removing the moisture, same works on soggy core. Any photos of this jewel with the areas in question? Yarning up a deck is one thing, moving tanks is another - but depending on how they were installed can be a saving grace for the project or the straw that broke the financial camel's back.

Situations like this is exactly why I don't like to suggest cored hulls to owners.

Remember: Nothing is impossible, you just need more preparations.

 

[jawz]

Couple of ways to deal with that,
1: a heater
2: yank them open from the outside and shove some antifreeze solution down into the core with a syringe
3: yank the inner layer off of the affected area &/or cut some holes on the exterior skin so that any moisture can migrate out, just be careful not to poke a hole through into the interior skin/fuel tank/holding tank/etc

Just because it's winter time and water tends to get hard doesn't mean that the moisture within the core won't leave, don't your lips get chapped during the winter months? That is because the air is removing the moisture, same works on soggy core. Any photos of this jewel with the areas in question? Yarning up a deck is one thing, moving tanks is another - but depending on how they were installed can be a saving grace for the project or the straw that broke the financial camel's back.

Situations like this is exactly why I don't like to suggest cored hulls to owners.

Remember: Nothing is impossible, you just need more preparations.

cored hulls scare me !
few people take the time to correctly install ANY thru hull - meaning,if anything's installed on a cored hull,the core must be protected.

balsa turns to saw dust when it gets wet,we all know this...

 

[BillD]

I'm looking at a boat that had a survey in 2010. The survey stated that the rear spray rails had been ripped off and the screw holes had allowed water in the core (balsa. H&H Built in 1994). Moister content was higher below the water line than above. I'm guessing this is a big problem. Or is it?
Is there a fix? Any thoughts or advice would be greatly appreciated?

Question?
Would the guys up @ H&H layed up a balsa cored hull as late as 1994?

 

[MASTERENEGADE]

My 35jc is cored. Coring can be a big issue if not properly maintained. My transom was soaked when i was looking to purchase the boat. I originally told the broker no thanks. In a contract agreement, they had eli laminants cut the outter skin of the transom and remove all the wet coring, then recore it with i believe nydacore. While this whole project was being done, part of the agreement was for my surveyor to be able to see every step of the job to inspect the work and inside of the transom. They did do a beautiful job.

When i replace my thruhulls and seacocks this spring. Every hole in the hull i dug out the coring about an inch and repacked them with fiberglass dust and west system this way the coring was now protected from potential moisture coming back in.

The other downside to a cored hull that is wet is that it may get heavy.

This is just my .02

 

[cardinal0128]

Hi all, I thought I'd post in this thread vs. starting a new one. In my cored-hull Sisu 22, I last year had a survey that showed the hull sound. It was previously and in-water boat, but it has been on a trailer for about six months and is only in the water for the day when it is used (2-3- times per month out here in CA).

Upon one recent haul out, the boat yard crew didn't line up my trailer perfectly and one of the rollers was out of alignment, causing a bolt to puncture the outer layer of the hull and expose the balsa core. Total size of the hole is maybe 3/8". Since then the boat has spent maybe 12 hours in the water, total.

We don't deal with freezing here, but I'm wondering what steps I should take from this point - just patch from the outside with a dab or 3M 5200 or West System epoxy? Is there some kind of moisture reading that I can have the boatyard undertake to see how much core got wet?

We don't have freezing here and again the boat lives most of it's life on a trailer, but I respect the danger that any exposure to water can mean for balsa coring.

 

[Brooksie]

Hi all, I thought I'd post in this thread vs. starting a new one. In my cored-hull Sisu 22, I last year had a survey that showed the hull sound. It was previously and in-water boat, but it has been on a trailer for about six months and is only in the water for the day when it is used (2-3- times per month out here in CA).

Upon one recent haul out, the boat yard crew didn't line up my trailer perfectly and one of the rollers was out of alignment, causing a bolt to puncture the outer layer of the hull and expose the balsa core. Total size of the hole is maybe 3/8". Since then the boat has spent maybe 12 hours in the water, total.

We don't deal with freezing here, but I'm wondering what steps I should take from this point - just patch from the outside with a dab or 3M 5200 or West System epoxy? Is there some kind of moisture reading that I can have the boatyard undertake to see how much core got wet?

We don't have freezing here and again the boat lives most of it's life on a trailer, but I respect the danger that any exposure to water can mean for balsa coring.

I have owned a cored DE for many years and have had a few wet core issues in that time most on deck or overheads and all were easily fixed. If I were you, I would tap with a small hammer/mallet around the hole to see if the core is wet, you will hear a different sound. Mark the area. Then drill a series of 3/16" holes around the marking thru the outer skin and coring to but not thru the inner skin, and make sure the core is dry there by feeling looking at the drilling "dust" that comes out. If wet drill further out. Then set up your shop vac on the original hole and pull any water out for several hours (sometimes days) until no more water in the hose. Let it dry as long as you can then inject epoxy into each hole with a plastic syringe starting at one side, plugging each hole as epoxy emerges from the next hole as you go across the drilled area from hole to hole. 1/2" #12 tapping screws are good to plug the holes. After the epoxy cures, remove the screws, fill the holes with thickened epoxy. "Sound" again with the hammer making sure all rock solid.

 

[cardinal0128]

OK thanks. Will a shop vac hold up that long, or is there some other kind of vacuum pump that should be used for this purpose?

 

[Brooksie]

OK thanks. Will a shop vac hold up that long, or is there some other kind of vacuum pump that should be used for this purpose?

I have run mine for days but if you had access to a vac pump, that would be better. And the neighbors would like it better.

 

[cardinal0128]

Got it. What is the best hammer to use for sounding? Ball peen, brass, plastic of some sort?

 

[Jangles]

Hard rubber mallet... smaller is better.

It's not an exact science, much like moisture meters, you will probably fool yourself quite a bit. The sound will change if there is a stringer or bulkhead tied into the area as well as layup thickness changes and de-lamination/voids. Making small holes is really the best way to be sure, though it does require patching.

Along with the vacuum idea, you can tent it and apply low heat which will also dry it.

One of the common issues with end-grain balsa is if the kerfs weren't fully saturated with epoxy, it can create little highways for the water to travel.