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like everyone else my 1983 13 foot Whaler has wet foam, I would like to use it this summer and do maintenance on it this winter. My plan for the summer is to cut a six inch hole in the floor about 2 inches in from the stern on the starboard side and put a watertight deck plate on. I would remove a six inch foam core down to the hull and when not in use remove the cap and allow things to drain naturally. Over the winter while working on the hull I would put about 100 lbs of Calcium chloride in various plastic containers and seal them in the boat while working on the hull. My questions are: would a six inch foam core being removed from that location adversely affect the hull integrity to a large degree (how thick is the hull?) while using the boat till winter? Has anyone had experience using Calcium Chloride to help with removing moisture from the foam?

Any thoughts would be appreciated

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The calcium chloride effort would be a complete waste of effort. How much water is in your hull? A few gallons won't hurt anything. How have you determined your hull has such a large amount of water as to necessitate it's removal?

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Thank you for the quick reply. I removed the screws that held a small bilge pump in place in the stern water trap that the previous owner had installed and water started coming up through the inadequately sealed holes. I use 10 pounds Calcium Chloride in my 34ft boat over the winter and all of it gets used up so i figured it would be a very affordable attempt at removing some (not all ) of the moisture in the foam. I have also read about an individual that routinely uses calcium chloride the dry out boats (Boston Whalers) that he restores and confirms this by weighing before and after. What is your opinion on the effect of removing a core of foam on the structural integrity of the hull?
Thanks again for the feedback

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Calcium chloride will absorb water from the atmosphere. The only proof it is getting water weight from the hull is to weigh the hull before and after.

As for removing the foam down to the bottom, you will be dependent on a 1/8" thick layer of not great fiberglass in the event of an impact on the bottom. Whalers are not strong because of the lay up of glass, it is the solid backing of foam that make them stiff.

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Recommend when you lay up your 13 for winter you elevate the bow as much as practicable. Remove the screws from the sump and any in the transom below the waterline. Use a sponge weekly to remove any water from the sump. Next spring you will probably find that the sump remains dry for several days. Use a good below the waterline caulk to reseal the screws removed earlier. Enjoy your 13. If doubts remain contine the following fall.

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I have used calcium chloride in measuring the moisture content of concrete slabs. It gets sealed onto the concrete floor. If you can reasonably enclose it for access to the hulls foam.....I could see the advantages for moisture removal. A very inexpensive and simple method for placement....leave it alone.....empty and refill the plastic trays/buckets. Do not use metal buckets, the calcium chloride will eat up the metal.

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I agree with the "complete waste of effort" crowd. This has been a bane on boaters for decades (wet foam) and attempts at drying the foam out have been futile in the short term. It is closed cell foam, and your hydrophilic material wouldn't have access to anything but the superficial moisture.

There was a guy that tried to save a 13 that was used for a mailbox for awhile. It weighed 800 pounds initially, and four years later still was wet even though in a heated garage.

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Are you saying that once BW gets saturated with water there is no way to dry it out? Did anybody else had that problem and how did you deal with it? You would think that putting some sort of hole, opening, drain plug in the bottom and keeping the boat in dry shelter would solve the problem???

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Hey chawk25,
This problem is not unique to Boston Whalers by any means, but what is unique is that the foam is a structural component to the hull strength hence the unibond design so cutting out the floor, removing the foam and refoaming is not going to work. How much water is in the foam? When I bought my 1968 13 to restore, my first concern was the hull weight since mine had all the classic signs that the foam could be wet but to my delight was dry as a bone. I borrowed a scale from work for weighing machinery, picked up the hull with an engine hoist connected to the scale and she came in at 280# without any interior which is where it should be. So weigh the hull first. Verify from the Whaler specs for your model and see what she weighs. If she's heavy, look at drawing 15013300 which is the wood locating diagram and look at the transom end view that provides the sectional view of the foam and transom wood configuration. Now this is what I was going to do if my hull foam was wet; above the hull bottom and below the floor I was going to drill a 1" diameter hole above the strakes on each side of the transom wood trapezoid, jack the bow up high or stand the hull up transom down of course and let gravity drain the foam over some period of time. I also considered drilling a 1" hole up in the original fill port where the foam was injected originally to allow air to enter as the foam drains. The holes can easily be filled and reglassed after the hull is drained. This process to me was the least invasive way to dry the hull out, it's just an idea that made the most sense that I was going to do if I had to.

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I was just curious. I've heard that is a problem with BW. I just got me an older (1986) 18' Outrage and got little wetness by the bottom of the transom where previous owner had transducer mounted. I removed the screws and stuck piece of wire in those holes. It came out little damp - but no water gushing out. I put a fan against it and will let it dry for couple days before filling the holes.
Watch this YouTube video!!!!

https://www.youtube.com/watch?v=bYizHBT5S5Q

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If you watch that video closely, you will notice that that boat has a drain hole made at the bottom of the transom. My boat doesn't. Even thou he has the drain hole notice how much water comes out when he drills additional holes!

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Any waterlogged Boston Whaler hull can be made perfectly dry. The question is, at what cost? If a hull is so waterlogged that it is no longer safe or capable of reasonable performance all the foam can be removed and replaced with new foam. This has been done and documented.

Most people would prefer to avoid buying a waterlogged hull. I would not accept one as a gift as I have neither the time, dollars nor skills to restore it properly.

Virtually every classic Boston Whaler has some water in it. If the water is not causing problems it is probably best left alone. To avoid additional water entering the hull it must be properly sealed. Every hull penetration including through hull drains or transducers must be proper caulked and any mounting screws/hardware well sealed and seated.

To avoid problems don't buy an overly wet hull and seal any hull you buy.

If the seller allows it remove one screw that penetrates the hull skin on the transom at a low point. A transducer mounting screw comes to mind. If water drains out for more than a few seconds a little suspicion is reasonable.

Lets assume you are going to do a little on the water test before buying a boat. Look closely at how deeply the hull floats. If you are unable to check the boat in the water try lifting the boat while it's on the trailer. Take a friend or two to help. Generally the smaller hulls can be lifted by hand by a couple of able bodies men. If you cant lift a 13 at the bow and at each corner of the transom you may want to reconsider the purchase.

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Chawk,

Did I understand correctly that your Boston Whaler does not have a garboard drain?

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My 18' Outrage does not have a drain plug at the bottom of the transom. I do have a drain in little bilge pump compartment, where all wires and cables come out from under deck, going towards motor. I don't think I have a water problem. As stated - I removed couple of old screws and noticed little moisture but there was no water coming out.

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Damp rid worked for me, I had a decent hull to start with, and it had access plates cut into to deck for a trolling motor, and I removed the through hulls. Put two big gallon buckets near each major opening, and sealed the top with plastic. Rolled it out in the sun everyday until the condensation inside stopped. Pulled about 14 lbs of water out, and everything was bone dry where we drilled. Works like a charm if you have patience. Took a few weeks. So those who say it doesn't work have no idea what they are talking about...

http://s1320.photobucket.com/user/jam...7.jpg.html

I've seen so many ways people have tried, including removing the foam and attempting to replace it, the issue is that when it's done, it can not be possible to replicate the curing density and adhesion to the glass, simply because you can't replicate the jig BW used to create these. My way seemed the easiest, most effective way.

I have a large scale drying I've I used on my 9' tender restore, it warped the glass. I wanted straight sides on the black one so it was my only alternative. Good luck.

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The key to any success using desiccant to dewater a Boston Whaler hull is sealing the space. If ambient air enters the space where the desiccant is located it will rapidly be dehumidified thus interfering with the hull drying process.

Certainly a 13 can be sealed up using plastic sheeting and, perhaps,
Gorilla Tape. You'll need to remove the engine and seal every hull penetration for this to be a decent seal. But, if the moisture egress is solely through screw hole the process will be excruciatingly slow. The larger the surface area of the wet foam the more efficient the process therefore for the process to be efficient any wet deck foam must be exposed.

Angus told us water started coming up in the bilge trap (sump) when he removed the bilge pump screws. He certainly has some water in the hull and it's likely to be found in the general area of the garboard drain. Whether or not it's worthwhile to Angus to open up the deck and later reseal it we don't know. If he is only able to remove 14 pounds of water I would not think it was worth the effort but he may believe otherwise.

Before taking on a project I would want to know if there is a significant problem.

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Has anyone though of vacuum bagging?

I would think it would work.

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Make friends with a carney. Put the 13 whaler on one of the spinning rides with the transom pointed out.
Pay for a 24 hour ride. Drill hole at the outermost and lowest point of the hull. Collect water.

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There may be a simpler method that I have been teasing to do myself. I had my hull surveyed and water intrusion (measured with the moisture meter) that was located by my drain tubes. My drain tubes have been out for a season air drying the area (I have been sidetracked working on a commercial salmon boat). As stated I have used the calcium chloride in the past. Sealing the area is the key. With my drain tubes out I have air access to the foam. Where convenient, this winter I may plug the hull side of the through drain and enclose the area on the deck side/cabin side (I have a 1979 22' Revenge) with plastic and a tray of calcium chloride and see if I get any type of moisture collection. This it the method used when measuring the moisture in concrete (you need a moisture reading in concrete for some staining and overlayments). I am pretty certain there will be a water collection. Before I start I will get the boat surveyer out here again to see how well the foam did with the drain tubes out. Calcium Chloride is the active ingredient in most moisture collecting products. You do have to seal it off from atmospheric intrusion to work. If a seal was broken with my concrete testing (I did several on the same slab) the results are thrown off. If moisture can be drawn from hardened concrete I do not see how foam with air access would be of any hindrance.
Garris

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I got a better idea: you ship that puppy to Arizona, leave it in the desert for a week and ship it back. I guarantee it will be bone dry. LOL

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I just bought a 1980 13 sport with a corroded drain tube - the outside 3in was gone. The foam at that point is damp- not soaked. I'm thinking of removing the entire tube and rigging up a pressure blower and blowing hot air through the hole. The air will dehumidify the foam. Not to get technical but once the edges of the tube hole dry out, the moisture further in the foam will diffuse towards the dry areas and be removed in the air stream. Even though the foam is closed cell, diffusion will move the moisture towards the drier parts. Worth a shot- the blower can run for weeks if needed

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Hi,
I was reading about this on another forum where one contributor said that blowing air in could cause delamination. I was going to rig a compressor with fittings to strategic places and a couple of holes in the bottom stern to let the moisture out, but now I'm not sure it is a good idea...

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You may be referring to a post I made. I was using a fine tip and an air compressor and inserting the tip into old screw holes to blow random water out. I was not attempting to dry foam. I did separate the foam from the inner deck, but was able to reattach it by drilling some holes and injecting epoxy.

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I'll be using a low pressure (<0.3 psi at the hole) blower but throttling it before it goes into the drain hole to get the heat of compression and warm the air stream. It's a warm mild breeze into the drain hole but it should dehumidify the transom somewhat over the many hours of running I plan to use. I'll report back when it's done, but it will be hard to tell how effective it actually was.

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Have you considered an electric leaf blower? Lots of volume, low pressure, etc.

Still a lot of effort for little return and probably not anything that will improve your boat in any measurable way.

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I agree that this may yield minimal results but it can't hurt. I'm using a blower capable of 15 psi and will throttle it to the low pressure- that way I will get the heat of compression and a warm air flow. A lot quieter than a leaf blower as well!

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You can also find a wet vac / shop vac with a set up where the hose can be plugged to the exhaust and used as a blower. A cheap hair dryer can be also easily converted to that purpose. I wouldn't leave any of the tools mentioned, run unattended.
Let us know how it turned out.
I haven't gotten any suggestions from anybody on putting a drain plug on my 18 Outrage. It came without one and I'm debating whether to put on? Or I'm I inviting trouble by having extra screw holes in the transom and allowing moisture in?

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A properly installed garboard drain is often useful. I recommend brass or marelon. I believe marelon is used on current production Whalers. Consider generous or possibly copious amounts of cauking to ensure positive sealing and protection of the foam and/or plywood from any possible water intrusion. FWIW, every modern Whaler I've seen has a garboard drain.

IMO, the brass tube and rubber stopper is not the best way to go.

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Thanks for the input. I've already have the brass garboard drain plug with 3 mounting screws and 1/2 drain plug. I was reluctant to install until I got second opinions. I have seen couple of older Whalers with drain plugs installed. The brass tube and rubber stopper would not be an option - you can't install them because there is a compression/ flaring toll required and you need access both ends with a wrench. You can't get to the inside of the transom at least on my boat. The same tubes are used in the splash well (access on both ends). Speaking of which, I think BW company didn't think this one out when they install those brass drain tubes in the splash well using O-ring as a sealant. These O-rings disintegrate quickly and allow water into transom. Better way is to put 5200 marine sealant and compress/flare the tube.

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Chawk25.....in agreement minus the use of 5200. That is an adhesive. Using it for brass tube replacement on the older hulls would trash the gelcoat. I used a more than generous amount of BoatLife LifeSeal in case I need to get in there again.
Garris

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Why would 5200 trash the gelcoat?
If you're worried about water intrusion I'd use the strongest stuff possible!
TP

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If you had to remove the tubes again they would be glued in place not sealed in place. Saving the through hull hole was delicate enough with the O ring design. A couple of my brass tubes failed from the foam side and the interior of the tube looked good with a visual inspection. If my tubes were 5200 in place I do believe I would ruin the surrounding area removing. The gel coat on my boat only a healthy 1/8" +- thick. The flange of the tube holds it in place. I do not believe the tubes were designed to be permanent. I do LifeSeal the heck out of it with the O ring. The water side of the tube gets installed first with generous sealant. I then flange the interior with as much sealant as possible without distorting the O ring. I found the sealant kinda acted like lubricant and the O ring would wander if I was not careful.
Garris

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http://i1320.photobucket.com/albums/u...fa42d9.jpg

The drains were my leaking culprit, and the first thing we addressed for restore. The holes were reamed, foam removed, and filled with the material you make transoms from, then they were drilled, and stainless thru-hulls. The stainless thru-hulls are for decoration.

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5200 and only 5200 for under water applications!!!
It can be removed, scraped off. Acetone will soften it up.

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I've also replaced my drain tubes with thru hulls and caulked with tons of 5200. One in anchor locker and one in the bilge hole where the wires come out. The nice thing about the later is that I can use that thru hull as hook up for a live well. Both of them are caped of with solid brass threaded cap. Another little trick you can try is to get rid of the awkward ground wire in the transom and hook it up to that thru hull. It grounds the fuel tank. Little tricky but it has been done. They use to make thru hulls with bonding screw but they are hard to find now. You can use ss clamp on the shaft of thru hull to clamp the ground wire. That way you have one less hole in the transom and one less wire hanging out there.

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For winter storage and to keep mold away, I know folks use Damp Away. I've also heard that some people use kitty litter as an alternative when storing the boat for the winter. Does this work and if so is it better than calcium chloride?

Assuming one of these methods work, could you reasonably expect to "dry" a completely stripped hull void of all hardware and drain tubes over the course of a winter if sealed in plastic and stored indoors?

One other though comes to mind in addition to all of the above is setting a dehumidifier in the boat with a hose drain coming out of the boat. Would this work?

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Other than stripping out the decking and replacing the foam nothing will COMPLETELY dry out an old Boston Whaler hull.

Since some water will remain in the hull no matter what you do short of the huge job mentioned why bother UNLESS you have so much water in your hull that it affects safety or performance.

I'm a pretty anal kind of guy and want everything in my life to be perfect but even I know when I'm spinning my wheels.

If you have a smallish amount of water in your hull it will not hurt a thing. Relax and enjoy your boat.

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Have any of the fellows using the 5200 ever removed the tubes after installed with that method? I base my opinion on seeing pictures of trashed transoms from motor mounting with the 5200. Quite a bit of discussion on the site on the use of adhesives vs sealants. Whalers original design was "O" ring only. I have also seen postings of using fiberglass tubes vs Whaler brass as well as closing off the holes entirely. I prefer factory original with this particular feature with the sealant as an upgrade.
Garris

Calcium Chloride is the active ingredient in many of the mold/moisture removing products. Keep it away from any metal. No longer being used as a concrete accelerator because it destroys the rebar.

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New Whalers use some kind of plastic, perhaps Marelon(?), hull and locker drains. They seem to function as well as brass tubes, don't use O-rings and are very durable. From what I can tell just from looking the drains appear to be seated in/sealed with a marine grade, below the waterline caulk such as that marked by 3M and Boat Life.

I believe the new drains are certainly equal to if not superior to the old. I am no longer able to do demanding hand work so have to pay someone if our boat's drains need replacement. Being a light spender I want the simplest least costly solution so will use the new style if they will fit our Sport 13. Purists will demand brass.

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I love these discussions, but if you tried my drying method in the beginning of the this conversation your hull would have the majority or all of the water out, and it would have only cost you $60.

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Removed the long drain tube and found free moisture in the foam. Not dripping, but wet to the touch. I've been running the blower for a while now with it blowing into the inside hole - the air is about 100F and I'm getting a high velocity air stream out the transom hole. Good conditions for the diffusion of the moisture into the air stream. The foam is now totally dry to the touch. The technique seems to work quite well. I'll keep running the blower to further dry the foam because it will be very effective in scavenging moisture. As I said earlier- it's virtually impossible to quantify the results but it does well qualitatively.

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An effective way to quantitatively know the result is to weigh your boat before and after some length of time. We know the weight of water and truck scales are quite accurate.

May I suggest, in the interest of saving energy, that you turn off the blower for a couple of days and check for wetness. If the area is wet resume the treatment until it is dry again, repeat until no moisture shows at the drain area foam. You will then know that you have dried your foam as much as possible without using more electrical energy than needed.

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I found quite a bit of water seeping from the corroded thru hulls of the 18 Outrage I am restoring.

I Used a number of approaches to dry the hull.

Since I am completely restoring this boat everything was removed, all screws, hardware, floor, gas tank... everything.

Then I weighted the boat to determine as I proceeded if indeed I was making progress.

I have access to an industrial air compressor system with an air dryer which removes the moisture from the air down to a -40 degree dewpoint (a very low RH or very very dry air). I sealed the boat with plastic and introduced the dry air (regulated to 2 psi) thru one of the thru hulls and allowed the interior to dry over a week to ten days. During this process I added a small heater in the interior to keep the air warm. So effectively the interior of the boat, all open screw holes (and there were lots of them) and the thru hull fitting were bathed in dry air. I do have to admit that while this approach seemed great, it only dried the surfaces.

Next I reamed out the foam from around all of the thru hulls. This I did to remove the foam which was most saturated and to provide space to seal these opening independent of the metal sleeve to be installed later. I then rigged a plug on one side of the thru hull and a second plug on the other side with a 1/4" poly tubing coming out of it. With a little silicone this sealed the interior of the thru hull and created a chamber into the foam layer between the hull and the interior FG. I applied a vacuum to the poly line and installed a "knock-out" bottle between the plug and the vacuum pump. This worked well and while I did not measure the water that came out, I did measure the differential weight which was 40#. That's 8 gallons.

I then centered a teflon rod thru the thru hull opening and injected heavy epoxy into the voids created by the removal of the foam. This created a complete seal of the thru hull openings and the metal sleeve will be added in order to keep the boat original.

Was it worth it? Well it does give me peace of mind that I'm working with likely the driest hull I can have and it won't happen again.