2008 285 CONQUEST: Water Intrusion

[Sandor]

[In August 2019] I purchased a 2008 Conquest 285, and I have discovered a major problem. I bought the boat in Long Island, NY. and shipped it to Southern California where it sat in the boat yard for three weeks getting new bottom paint, a little engine maintenance, and new electronics. During this time I did some deep cleaning and discovered the boat had mold and mildew in all the spaces and voids where wires are run. I cleaned everywhere.

In the forward bilge and storage compartment in the mid berth behind the companion way (as pictured below) I discovered a 10-inch round fiberglass lid that was loose and peeling off. I removed it and the thin layer of silicone revealing the foam core. Apparently this is where [Boston Whaler] injected the foam during construction. [The foam in the interior of the Unibond hull at this location] was soaking wet.

Fig. 1. Wet foam at Sprue hole. There is a gap between the laminate and the foam at one side.

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I thought maybe [the foam had become wet] just from the water I used to clean the area, and that [the wet foam] was on the surface ONLY, of course, because of the closed cell foam. We dropped the boat in the water and put her in a slip. For the last two weeks I have had either a fan or most recently a dehumidifier running right on top of the foam [at the sprue hole] and it is still soaking wet.

Fid. 2. Mid berth storage compartment with dehumidifier.

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Fig. 3. Mid berth area.

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When we first dropped the boat in the water I noticed both fish hold boxes were filling up with water all the way to waterline. I pumped out the water and it would fill up again. I pumped out the water and quickly dried it with a towel to see where the water is coming from. It is not the plug, it is leaking from the plastic through hull fitting itself.

Q: Is [water leaking around the plastic through-hull fittings] the cause of the wet foam?

The previous owner also kept the boat in a slip during the summer. Yes--I had the boat surveyed and specifically asked the surveyor to make sure the boat is dry. The surveyor told me he could not use a moisture meter on the hull because of the bottom paint, but that he would check it above deck. The surveyor did not report any of these concerns to me.

This is my worst nightmare come true with buying a boat. I went way over budget hoping to avoid these kinds of problems. I need to find out if I have any recourse with the seller, surveyor, and Boston Whaler. Otherwise just fix the boat and use it.

My current thinking is to haul the boat back out of the water and remove the two thru-hull fittings from the fish holds, open up a bunch of holes in the hull, and let it start drying out for the next six months or more.

Any experience, suggestions, and support would be greatly appreciated.

Thank You,
Sandy

[biggiefl]

You know the water did not get into that [under deck mid-cockpit] area as it is not in the weather.

Q: Can you take a pic of the area you think the water is coming in from?

Water in fish wells would not saturate your foam, only a major breach in the hull. Usually what people think is waterlogged is just some water on top of the foam or below it. Closed cell foam (for the most part) can not get waterlogged like a sponge and hence its name.

With a 2008 it is probably time to replace the plastic thru-hulls. You need to find out why there was water on top of the foam there and where did it come from and has it stopped.

As far as declaring the boat waterlogged and a salvage vessel is probably not in the cards.

Q: how does it perform compared to other 28's?

If a hull was truly waterlogged at 8-lbs per gallon, you would not be able to get on plane.

[jimh]

The circular cut-out seen in Figure 1 is the SPRUE HOLE. In molding the hull, the sprue hole is typically the point in the molds where the foam is introduced (as a liquid) and then later escapes during expansion into a foam. After the foam has cured into a solid, the sprue hole is capped with a thin laminated cap. This is a feature common to many Boston Whaler hulls. The location of the sprue hole varies from model to model.

I do not think that blowing a fan to move air across the top of the sprue hole is going to be particularly effective at drying the foam, and a de-humidifier probably even less effective.

I recommend you check with Boston Whaler customer service for further advice.

One idea that comes to mind: perhaps a hole of say 0.75-inch diameter could be bored downward for about six-inches into the foam that is exposed at the sprue hole. Be sure to check with Boston Whaler if this is possible, as there could be other elements deeper in the foam that are passageways or shear-tabs for bonding the inner and outer hull together. Assuming the hole is safe to make, then If this hole then fills with water, a hose could be put into the hole and led to a pump. The pump would then pump the water out and overboard. In this way perhaps more water could be extracted from the interior foam.

[jimh]

When we fist dropped the boat in the water I noticed both fish hold boxes were filling up with water all the way to waterline. I pumped out the water and it would fill up again. I pumped out the water and quickly dried it with a towel to see where the water was coming from. [The entry point of the water] was not the plug, [water] was leaking from the plastic through-hull fitting itself.

You describe the through-hull fittings that drain the cockpit fish boxes to the sea as leaking and allowing seawater to enter the fish box. If this is true, then the through-hull fittings must also be allowing sea water to have access to the interior foam of the Unibond hull.

A possibility comes to mind:

Q: is the water that collects in the deck fish boxes seawater?

Q: is the water clear and without an acrid odor?

If the water is seawater (saltwater) and does not have an acrid smell, then the water is probably coming from the sea. I was thinking perhaps the water was coming from water already in the hull interior space, leaking out via the through-hull into the fish box. I hope not.

I recommend the boat be hauled out of the water, the leaking through hulls be removed, and the interior foam of the Unibond hull be examined for water intrusion. If the foam is wet, the boat should remain out of the water an be allowed to thoroughly dry. Once the foam seems to have shed any water--which could take some time to occur--the through-hull fittings should be replaced.

[jimh]

[In August 2019]...discovered the boat had mold and mildew in all the spaces and voids where wires are run.

Generally mildew occurs with fresh water. The boat must have collected some rain water. Add warm weather and you get mildew. My 1990 boat has been used extensively in freshwater and has collected some rain water. If you crawl into the deck fish box and look at the undersides of the deck, you will see some black mildew.

[NLA01]

Sorry to hear about your boat letting you down with the water intrusion but I doubt very seriously your hull is full of water. I would recommend NOT to drill a bunch of exploratory holes all over your boat trying to drain water from it. I would, though, buy yourself a moisture meter and test the fiberglass around the areas you are concerned. I believe you are looking for 10% moisture readings max.

I would pull the boat from the water and pull those through hulls, put a moisture pulling vacuum on those areas (one used for vacuum bagging fiberglass) dry out the foam around and put in new through hull.

I would compare your static trim to other boats with your power and model and see if your boat is lower in the water.

I would NOT drill down into that foam just yet until you know for certain you are not causing unneeded damage.

Is your boat listing to one side?

Closed cell foam does not collect water but water can migrate around the foam and then when it freezes can cause damage to the foam and then allow water in the damaged foam. Repeat this over several winters and now you have water in your foam, but not all of the foam, just what is damaged.

There are some urban myths about whalers and miss information. A hull that is 40 years old that has sat out in the weather just might have foam soaked up with water. But I doubt this is the case with your boat. I would be way more worried about delamintaion and have the hull tapped on with a small mallet looking for delamination area.

I would call Whaler and talk to them about this and I would bring it to a Whaler certified repair shop to look at it.

There is no recourse to your purchase when it comes to the surveyor and the seller. And there is not perfect used boat. I am hoping this is not what you think it is.
Archie

[Sandor]

Thank you for very helpful and insightful information.

The water around the sprue hole seems to be greater in the area toward the bow. When I apply pressure on the forward edge of the sprue hole, water comes up through the cracks.


And I am relieved to report the foam is not nearly as wet as I had thought. There are two cracks in the foam. The water is coming up through the cracks and the surrounding foam appears to be dry. I made small incisions which revealed the dry foam

Q: what caused the cracks in the foam visible in the sprue hole?

Q: how much water is in there?

Q: where is the water coming from?

I did have a hose running in there when I first received the boat to clean out that area. That area was full of funk and grime.

I am going to haul out the boat to replace those two through-hull fittings.

Q: should I sand off the bottom paint and look for damage to the hull?

The paint on the engine gear case skeg is worn off about three-inches up. I wonder if the boat ever went aground.

Maybe the cracks in the foam were caused by the freezing temperatures as Archie suggested.

Again, thank you all so much. In gratitude--Sandy

[Sandor]

The boat does list to port.

A battery and inverter were added in the storage compartment to port adding about 120-lbs. I also added chain to the anchor locker that weighed 45-lbs.

I do not have experience driving other deep-V CONQUEST hulls, but this boat does list quite a bit while on plane. It will list to port, and then if I adjust the trim tabs it may level off and then list to starboard. Judging by the bottom paint it is a little bow heavy. Static waterline is 1-inch ABOVE [I think you mean BELOW--jimh] bottom paint at bow, and about 4-inches ABOVE [BELOW--jimh] at stern.

Fig. 4. [View of static trim at the bow; bottom paint appears to be above the water line. Bottom paint at stern seems to be several inches above water line.--jimh]

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[biggiefl]

Where are your registration numbers?

If you had a hose in there and that seal was not sealed, you just got your answer.

Yes 120-lbs will add a list to one side. Maybe put the 45-lbs of chain on the starboard side. I would inspect the hull but would not sand off the paint. If there was damage and enough of it to let water intrude, you'll see it with the paint on.

Drive the boat, take some numbers on performance and post it and see what other owners think about it. With WOT speed make sure you are trimmed out to the max please.

[Mr 88]

If the boat is documented no registration numbers are required by federal law. Name and home port are and they are put on the stern. Documented numbers are placed in a out of the way location and if removed they should leave a shadow,imprint .

[Sandor]

Yes, this boat is a documented boat.

My plan is:

• to haul out in a few days and remove the through-hull fittings [in the fish boxes].
  
• Then to see if water is also coming from somewhere toward the bow, say from a small hole or one of those plastic through-hull fittings toward the bow.
  
• to tap out the hull to find any delimitation.
  
• to maybe use an infra-red imaging device.
  
• to maybe use a vacuum to pull water out from the hull. I don't think the foam is waterlogged, but there is water in the hull.
  
• to let the boat dry out and fill any voids between the foam and skin with resin.
  
• to replace all through-hull fittings.

GIve me an opinion on my plan.

Q: what through-hull fittings to best to use?

Q: should I use new plastic ones from Boston Whaler?

Q: should I use quality stainless steel?

Q: should I use bronze?

Q: will metal through-hull fittings need to be bonded?

Q: what is a meant by the term "bonded through-hull"?

[jimh]

Q: what is a meant by the term "bonded through-hull"?

Generally all metal fittings that are always submerged in the sea should be part of a fiberglass boat's bonding system.

A bonding system on a fiberglass boat is an electrical circuit that is designed no carry no current from any electrically operated device, and is an isolated circuit that connects all metallic components of the boat fuel system and any metallic components such as through-hull fittings that are immersed in the sea. The bonding system typically is connected to its own under-water electrode to establish a good connection to the sea, or to the boat's negative 12-Volt DC power distribution system at a primary distribution bus. The bonding system cannot be connected to the boat electrical system in more than one place, in order to avoid a loop which might carry inadvertent electrical currents from other electrical devices.

To gain a better understanding of boat electrical systems, galvanic corrosion in water due to immersion of dissimilar metals, and bonding systems designed to prevent electrolysis, I recommend buying a well-written, respected book on those topic.

[jimh]

Re the present trim on the boat compared to where the anti-fouling paint was applied as shown in Figure 4: to make an inference about the presence of water in the hull based on a comparison of the current static trim to where the anti-fouling paint was applied previously is difficult.

As I indicated parenthetically in your comments, the photo of the bow shows the hull is floating higher at the bow and at the stern than the anti-fouling paint line. From that I infer the weight of the boat at present is no more than the weight of the boat in the past when the anti-fouling paint was applied.

If you have a really high-resolution image of the water line, email it to me and I will crop it to show just the water line areas in greater detail.

[jimh]

Q: what caused the cracks in the foam visible in the sprue hole?

The process of making very large, say 28-foot, Unibond hulls is somewhat of a trade secret at Boston Whaler, and the exact process is not particularly well-known.

That the appearance of a crack in the foam at a now exposed sprue hole is evidence of a hard grounding of the boat is very speculative.

Contact Boston Whaler customer support with your question about the appearance of a crack in the foam visible at the sprue hole on your 2008 285 CONQUEST, and ask them if there is anything unusual about it.

[jimh]

In Figure 1 we see a Sprue hole. There appears to be some shrinking of the foam and perhaps some loss of sealant between the foam the laminate, particularly on the portion of the Sprue hole that is at the bottom left of the circular opening of the Sprue hole in the image. I believe this is in the direction of the boat's bow.

It is known that there can be some slight contraction of the foam as it cures. This may account for the slight gap between the foam and the laminate at the Sprue hole, and the apparent loss of a seal at that point. This may have allowed water that was being used to wash down the boat to enter into the spaces between the foam and the laminate at that point.

In your list of planned actions you say:

...to maybe use a vacuum to pull water out from the hull.

Use of a vacuum bag to pull water out from the area at the Sprue hole sounds like a good plan to me.

[Sandor]

I have not hauled the boat out yet. We used a PPM-meter and have determined saltwater is coming out of the sprue hole. I just hope the saltwater is coming from the fish boxes.

[jimh]

What is a “PPM-meter”?

[Sandor]

[A PPM-meter] measures solids in the water at parts-per-million. The water in my boat was 2000-PPM so definitely seawater.

[jimh]

One reference says the salinity of the ocean is "35 parts per thousand" which in units of parts-per-million would be 35,000-PPM.

That your measurement found only 2,000-PPM suggests to me that the water, if originally from the ocean, had become significantly diluted with freshwater.