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  • #7800
    Anonymous
    Inactive

    I’ve got the leak between the gunwale and the rear bouancy chamber that Swiebertje refers to, as does The Book on page 17 (fourth edition). The Book says that if joint has become detached then it will need to be repaired professionally. This seems to be my situation, as there is distinct play between the gunwale and the tank.

    I tried the smoke pellet test, and found that smoke came out round the seals of the hatch and at this weak point on the gunwale. It was impossible to get any over pressure at all by blowing into the rear chamber (even after I’d put the inner bungs in 🙂 ).

    I happen to have some Sikaflex, so I guess I can try your suggestion, Swiebertje, but the surfaces are so complicated that I am not optimistic of fixing the problem.

    There is other correspondence on replacing the seals, and where to get new seal material from. Mine look in reasonable condition – but do they just get tired and go slack? It’s obviouse from the smoke test that when the hatch cover is clamped well down, the join still leaks. Is that proof that the seal has lost its umph?

    #7803
    krgough
    Participant

    Hi,

    Luckily for me I don’t think that joint has failed. Imagine looking into the gutter from inside the boat (looking parallel to the transom) under the side deck. There is a flange from the tank that forms the back of the u-shaped gutter and it joins to the transom as described in the other mails. My damage is in the front edge of the U-gutter. Difficult to describe.

    Anyway it’s a right pain in the wotsit because I only have a small inspection hatch so I don’t think I can reach this from inside.

    My hatch is also leaky but I’m confident I can sort that out with some sikaflex. I can get some pressure but you can hear the hissing from the corner and if I stop puffing it fades away after a few seconds.

    regards

    Keith

    #7858
    krgough
    Participant

    Hi Folks

    I’ve had an interesting day. I think I’ve managed to seal my rear tank. In the photo below you can see a light patch in the gutter. That’s the “repair” to the damaged spot. I also had to remove and re-sikaflex the inspection hatch. I’ll know tomorrow if that has worked, but today with tape over that hatch I counted 30s for 5 inches to 2 inches of pressure so I’m calling that a pass.

    Then onto the front tank. Not able to get any pressure at all, so I knew there must be a leak somewhere. Took out the front benches and crawled in to have a look at the seam along the inside of the hull above the tank. A couple of bits of damage found that look like they match some crazing in the gel coat on the outside. My guess is it’s had a bump there in the past. I put some soapy water on and bingo….

    I’ve poured some resin into these cracks and I’m hoping it will have set by tomorrow so I can try again.

    regards

    Keith

    #7893
    krgough
    Participant

    Hi,

    I’m now legal as far as buoyancy tests are concerned. It has taken about 3 weekends to find and seal all the leaks. At one point I had to crawl on the shelf under the foredeck all the way to the bow. What a grim job. There must be a better way of making something float.

    regards

    Keith

Viewing 4 posts - 16 through 19 (of 19 total)
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