Water in sealed hull?

[Paikea]

I have a problem!

When I removed the existing Transducer bracket from my Tournament 1800 a stream of water came out of the screw holes.

The total volume of water amounted to three buckets. The colour of the water was like tea or tannin stained. Much as you can see in freshwater creeks.

The problem is that I don't know how the water got there. The hull either side of the central well (the well runs full length of the cockpit and carries the 160 L fuel tank and live well) is fully sealed. It has fibreglass stringers and cross braces also of glass that are bonded to both the bottom of the hull and the underside of the floor. the areas in between the stringers/box section are filled with flotation material.

I have gone over the floor of the boat and not found any holes or cracks that may have let the water in. Removed the carpet, again, no entry point for water.

The bottom of the hull looks sound, no apparent cracks or damage.

The previous owner was not aware of the water being there. He operated the boat in freshwater only (Skiing on Lake Jindabyne) and never noticed anything untoward.

The manufacturer was not able to shed any light on the problem other than to comment that once a boat leaves from them they have no control over what is done to drill/seal any holes in either the transom or the floor. Fair comment.

As I have not been able to find the entry point for the water my problem is, can I safely take the boat to Browns on a good day or should I be worried that water will again find its way in the hull and possibly create a dangerous situation? As shown in the picture of the transom I have added a drain plug at a point below the holes where the water came out. Despite the fact that the plug is located below the level of the transducer holes no water came out of this hole. I assume that this is because the plughole is to the other side of the (sealed) area that contained the water.

I would appreciate comments from any experienced boaties, also, if anyone has a pic of the stringer/grid layout of the 1800 before the floor is attached that would be most helpful to get a better understanding of the likely entry point of the water.

Thanks

Paikea

[Geoff]

I.m not familiar with this type of boat but a few comments that may be of assistance.

Did you taste the water , fresh or salt?? I suspect from the colour it is fresh which means the water entered during the previous ownership.

There appears to be no sealant around the tranducer bracket holes. Is it possible the water seaped over a period of time when the boat was just sitting in the water.

I assume all the water has now drained out . Perhaps take it for a run , say for half an hour or so on the plane .

Some times cracks not visable when on the trailer will open up when under pressure on the water.

Trailer the boat & check for water. If nothing then the hull is OK.

Relaunch & let the boat sit near the ramp for a period then retrailer & check for water. If there is water then it's entering around the transom. The question is then where.

Geoff

[Paikea]

Thank you Geoff, the previous owner told me that he only used the boat for skiing, in and out of the water on the day then stored in a garage.

I wondered whether the water may have got in through the screw holes but if it did why did it not drain out during storage?

The whole thing is one big worrisome mystery.

I will try your recommendation as soon as I can, still sporting a "moon boot" as a result of a torn Achilles tendon so it will be another 3 to 4 weeks before I can try it out.

Cheers

Paikea

[brickman]

i feel your pain hears what to do you need a compresser and a spray bottle with 4 parts water and one part dishwashing liquide now hears the important part you need to presserise the hull but be CARFULL!!!!!!!!! get a mate to wedge the air hose in the hole with a wet rag and no more than 5 psi or you could pop the hull spray all over the hull and floor with the spray bottle and look for bubbles a small leak will foam up you can spray as many times as you like and foam[small bubbles will apear] this is how we check fuel tanks for leaks i can't stress how important it is to not seal the air hose in the hole i have seen an aluminium truck fuel tank pop an end off and break the dills arm that was testing it good luck cheers gary

Edited July 26, 2013 by brickman

[a boat]

Hi, for water to get in there it will be from either crack in the hull, which should be pretty visable and you say you can not see one so that is good or from where the tranny screws were not sealed when first installed. The drain hole you have added closer to the keel will be into a different area under the floor and water from there would come from the centre cavity of the hull. Either side of this are sealed (or at least should be sealed) cavities that do not want water in them. When you can seal the old holes, seal the new tranny holes and do what Geoff suggested.

One thing is the boat should ride better now because that is a fair amount of water to come out and having that weight on one side of the hull would not help with the way it rode.

Cheers,

Huey.

[Geoff]

Paikea Huey raises an inportant point,

The drain hole you have added closer to the keel will be into a different area under the floor and water from there would come from the centre cavity of the hull. Either side of this are sealed (or at least should be sealed) cavities that do not want water in them

If the water entered via the screw holes & those holes have a stinger between the holes & the new

drain plug then the water is retained in the "screw hole" section & not migrate to the drain plug.

In respect to your question ,

I wondered whether the water may have got in through the screw holes but if it did why did it not drain out during storage?

My boat is a twin hull with the sponsons fully sealed (air tight) . Each has a bung & regardless of sealing washers or the use of plumbers tape around the thread , a small amount of water is sucked in due to the temp variations, ie on a hot day with the boat on the trailer the hull is hotter than the water. Launch the boat into cold water & the contraction of the air inside the sponson sucks water in via the bungs.

When back on the trailer the temp change is insufficent to force the water back through the bung holes.

I'm not suggesting your boat has a similar situation (air tight) but when in the water , the pressure is sufficent for water to migrate via the screw holes but insufficent to drain out when on the trailer.

Geoff

[Paikea]

Thank you Raiders, your input is much appreciated.

I just cannot get my head around how the hull could possibly be split. The way that boats are built today, particularly by reputable builders like Tournament (formerly Mustang) would appear to exclude that possibility. But, you never know so the bubble test seems like a reasonable idea.

Anyone know what pressure the exhaust from a vacuum cleaner runs at?

Sucking in water through the screw holes that fasted the transducer sounds feasible but 20 Litres through the thread of 2x 4mm screws? That seems a big leap. I even wondered whether it may have been put in the hull by a disgruntled employee (sabotage) but if that was the case it should have run out when the transducer was installed.

The worst part is the uncertainty. On the one hand I hope that the bubble test does not reveal any problems with the hull but on the other hand if we do not find any reason I will always be worried that water is still getting in.

We will keep searching and post results (if any)

Cheers

Paikea

[Testlab]

The reply I posted the other day didn't appear so I'll type it again.

The colour of the water in the bucket is really dark and looks much darker than I would expect from a lake. Having had a similar experience with an old Savage where a lot of water came out of a buoyancy chamber unexpectedly (the water was very dark brown) I tracked it to a leaking joint between hull, floor and chamber. The really dark water was caused by gum leaf tannins from my tardiness in cleaning them away.

In your case apart from sealing the transducer thread holes I would look at all the internal fittings and make sure they are sealed where they penetrate the floor or could allow water to enter through pockets and storage boxes along the side of the cockpit. Seat bases, cleats, rod holders, tie downs may not have any sealing applied or its failed. Since it was used for skiing check the ski pole mount hasn't fractured (if it's the socket type) or there isn't any cracking around it and the screws are sealed.

Pressurising the hull sounds like a good idea and I doubt a vacuum cleaner could generate enough pressure to do any damage but as brickman said don't seal the hose to the hull. I would connect the air source up to your extra drain hole and then see if you feel air leaving the transducer holes to check if they are connected (there might be a stringer that stops water getting to the new drain but doesn't extend full height to the floor). If you've air flowing then do the soapy water test once all the drains and known holes are plugged.

Good luck with it.

[Paikea]

Thank you, I have just contacted Haines the new owners of Tournament and asked them to send me a pic of the stringer layout before the floor is installed. That will give me a better idea as to the size of the compartment that the water came from.

I am also thinking of drilling a small hole in the port side to check if there is any water there.

Finally I may hire an inspection camera to go through the screw hole and see if that will reveal anything. If that does not work because of the presence of foam flotation I may look at installing a 150mm inspection port in the floor to remove the flotation and have a good look from the inside. Driving me nuts!

Maybe sealed hulls are not such a good idea where you are not able to determine whether any sealed section has water in it without drilling a hole to find out ? Maybe there is merit in all sealed sections being fitted with bungs to allow regular checking for the presence of water? Any comments?

Cheers

Paikea

[Testlab]

I thought there were always limber holes or transom drains for the exact purpose of checking for ingress.

[brickman]

i know how this is playing on your mind my first boat had the same drama not a sealed hull but 3 eskys off water after one trip freaked me out if it would help you can bring the boat to silverwater and i'll help you test it, it should only take 2 hours on a saturday your call mate but the offer is there cheers gary

[Paikea]

Brickman

Thank you Gary, much appreciate your offer.

I am not able to drive for a further three weeks (moon boot on right foot) so cannot get over to Silverwater until then.

If I haven't solved the problem in the next three weeks I will give you a call. Thanks again for your kind offer.

Testlab

Re Drains etc, so did I, but apparently some later model boats are fully sealed with no connections between sections and no transom drains other than the central well. My previous boat, a Trailcraft 5.1 Centre Console was self draining and had a sealed section under the floor which all drained via one central bung in the transom. (see Pic)

Maybe Huey can throw some more light on this?

Cheers

Paikea

[a boat]

Hi, it will be interesting to see if Haines emails you this picture-it would be something a lot of glass builders would not want to give to the public. From what I know of Tournament they would have two "sealed" chambers either side of the centre area and really should not have water in them.

Cheers,

Huey.

[boattart]

Also consider the entry point for the cable. When my boat arrived both those domed covers where the cable entered were leaking and taking quite a bit of water when the boat was loaded up.

[Paikea]

Haines who have just purchased the Tournament range of boats kindly sent me a pic of the stringer system for a 1750 Tournament. They did not have an 1800 on the line at present but the system is the same for both. (although the 1800 grid is slightly wider)

To say that I am impressed with the stringer layout and detail is a vast understatement. The whole system is so rock solid that I cannot see a hull ever splitting or being seriously damaged.

So it looks like the water in my boat did come in through the transducer screw holes and possibly screws in the floor holding the battery and oil tank in place. As these have now all been sealed I am confident that the problem will not reoccur. However, after a few runs in the boat I will remove the screws again to check.

Thank you all for your input to solving this problem. Nothing like kindred spirits to look at a problem and offer suggestions. That is what I really like about this site.

Cheers

Paikea

[wizza]

hi Paikea i had avery similar leak.my tradie nephew looked everywhere and found no cracks. He then carefully applied sikaflex around the bungholes and not a leak now for 2 years. good luck wizza

[Paikea]

Geoff made the following observation re a potential source of the leak in my boat:

"My boat is a twin hull with the sponsons fully sealed (air tight) . Each has a bung & regardless of sealing washers or the use of plumbers tape around the thread , a small amount of water is sucked in due to the temp variations, ie on a hot day with the boat on the trailer the hull is hotter than the water. Launch the boat into cold water & the contraction of the air inside the sponson sucks water in via the bungs.

When back on the trailer the temp change is insufficient to force the water back through the bung holes."

Having determined that there are no cracks, splits, holes or other sources for the leak I checked the temperature records for Lake Jindabyne and found that the temperature differential between the Lake water and on land temperature can be as high as 25 degrees.

That differential would certainly be enough to create the situation described by Geoff so I am now much happier that proper sealing of the screws will have fixed the problem. However I will still check by removing the screws once I have some hours up in the boat and reseal them.

Quite a lesson learnt from this problem. In more than 50 years of boating and having owned more than 14 boats ranging from Game Boats to a dinghy during that time this is the first time that I have struck anything like this. Shows you are never too old to learn.

Thank you Geoff for your insight into the problem.

Cheers

Paikea