Water in hull - 9 months later

[Ally S]

I sent a post at the end of last summer about a problem we had with our redbay and got some helpful responses, but sadly we seem to have failed to solve the problem. Any clever ideas would be gratefully received as we're now at a total loss what to do next!

We found a lot of water in the hull after our rib had been out of the water for a few weeks and we couldnt drain it through the drain plug in the transom. We assumed the drain holes in the stringers within the hull had blocked and therefore, following advice from Redbay, we drilled two further drain plugs either side of the transom, which successfully got the water out.

Having emptied the hull we had to find out where the water was getting in..as it seemed to be fresh water, with a bit of a fuelly tinge to it, we assumed it was getting in from the deck. We therefore filled the boat up and blew compressed air through the drain plug. We saw air bubbles coming through the elephant's trunk attachment, where it is cut through the transom. Joyfully thinking we had found the issue we went to work with the sikkaflex and looked forward to a summer of hassle free boating!

Sadly it wasnt to be. Water still seems to be getting in and we tried the compressed air test yesterday but could see no air bubbles. Strangely the boat was dry having been on land for a few weeks (although there has been v little rain up here), we then put her in the water for a wee burl and when we took her out there was some oily water again. So now we are wondering if it is actually getting in through the deck or through the hull.

Basically we now have no idea who to turn to or what to do!! Has anyone experienced similar problems or got any clever ideas?

Many thanks
Alasdair

[jwalker]

I don't know the structure of your hull but could the last water have been trapped behind obstructions and simply made its way to the drains while the boat was in use?

Why would it be oily? It may smell of fibreglass catalyst though; it takes a few years for the catalyst to be eliminated from the laminate.

I've said it before on ribnet but I don't consider elephant trunk bailers which are just held in place and sealed with sikaflex to be satisfactory. Any leakage there will risk water ingress to the transom wood.

[Chris]

Originally Posted by jwalker

I don't know the structure of your hull but could the last water have been trapped behind obstructions and simply made its way to the drains while the boat was in use?

Why would it be oily? It may smell of fibreglass catalyst though; it takes a few years for the catalyst to be eliminated from the laminate.

I've said it before on ribnet but I don't consider elephant trunk bailers which are just held in place and sealed with sikaflex to be satisfactory. Any leakage there will risk water ingress to the transom wood.

That's a really valid point, I had to tip my old RIB right up on the trailer to get water to drain out as it seemed to get trapped further up the Hull. You may well have. sorted the problem already its just getting the last remnants of water out that will take some time.

The place I found some water could come in is via the opening to the cable ducting in the rear transom boxes. The ducting then goes under the deck and Osprey drill holes in the bottom of this to allow any water to drain into the hull as its better there than pooling in the bottom of the ducting.

[Hugh Jardon]

Originally Posted by Chris

The ducting then goes under the deck and Osprey drill holes in the bottom of this to allow any water to drain into the hull as its better there than pooling in the bottom of the ducting.

my understanding is that mike is very reluctant to drill holes in that ducting to let water out and will typically only do it under strong request

[Bigmuz7]

Cant speak for Redbays only.. but the principals are the same, most ingress I have encountered are via deck mounted structure. (take it your Redbay stuff is bonded though) If your gonna blow air up the under deck.. you need to have 5 peeps with soap on hand to see all the air come out !! 1 wont do . As JW said trunks are a pain too, most of mine have not sealed but they are quite easy to spot so I doubt thats your problem. More than likely its a small deck hatch somewhere,or something similar.. sealed though they are supposed to be.. have you got any of them ? Im always surprised at how small a leak can gather a lot of water, particularly if its in a path of water getting shedded by a console for example..Or its some other fitting you got added perhaps by a third party, who didnt seal it correctly,. or does you fuel tank sweat on the outside a lot ?

Best of luck though as I know how annoying this is

[Chris]

Originally Posted by Hugh Jardon

my understanding is that mike is very reluctant to drill holes in that ducting to let water out and will typically only do it under strong request

It was Mike who told me they always do it so maybe they have changed their ideas on that?

It would strike me as the better option.

[Ally S]

Thanks for the advice - appreciated

We dont have any deck hatches etc and the jockey seats are bonded onto the deck, so we are hoping that it was indeed just the remnants of previous water coming through having been freed up when the boat was more tilted on the trailer - i guess time will tell.

Still not entirely sure that there isnt some water getting in through the elephant trunk, and this would explain the oily water as there is some oil / fuel residue in the bilge. If the problem does persist our next idea is to fill the bilge up with water with a few drops of food colouring..if the water getting through into the hull is blood red then we know the leak is coming from there!

Cunning, but hopefully its just residue.

Thanks again
Alasdair