Keel repair?

Discussion in 'Sailboats' started by Goingdef, Oct 21, 2013.

  1. Goingdef
    Joined: Oct 2013
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    Goingdef Junior Member

    Hi everyone this is my first post as I have found myself helping my father with his 40' hunter sailboat. The issue I'm facing right now is the keel was weeping even though it's steel? So I sanded down the area and found a 10"x36" strip of what looks like fiberglass resin stressed with multiple cracks! So I found the slow leak for the center keel bolt:eek:

    So what I'm trying to figure out is how far do I take this area down to fill it back? I realize pulling the keel is the ideal situation but honestly my father is quickly going broke trying to get his dream to come to life, so at this point it has to go back in the water in the next week or so as it's been in the yard for the entire summer and this problem was just noticed by myself so I volunteered to help.

    On the plus side the other four keel bolts aren't leaking and it only seems to be the center one if that means anything?
     
  2. michael pierzga
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    michael pierzga Senior Member

    Dont know the keel details. Sounds like a leaking keel bolt. Take the nuts off, clean up the thread and washer then rebed into sika flex or other compound , then torque the nuts.

    Google keel bolt torque and you will find bolt diameter torque settings.

    Outside on the keel a typical detail is to cover the keel to hull joint with a layer of fiberglass cloth to prevent the joint for showing. This is a cosmetic detail. Identify this joint and layer of fiberglass cloth...grind it back...then replace with a new layer of cloth. Biaxial 45 45 eglass. , medium weight, say 12 inches wide...set in epoxy ...wrapped around the leading edge and mated on the trailing edge is the typical repair

    A weeping keel to hull joint is a very common repair. A weekends work
     
  3. Goingdef
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    Goingdef Junior Member

    Here's a picture of the area in question.


    Once I figure out how to post a pic?
     
  4. Goingdef
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    Goingdef Junior Member

  5. Goingdef
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    Goingdef Junior Member

    We've clean it down about 1/2 and removed all the cracked resin, it looks to be a poorly done repair but it could be factory I'm really not sure?
     
  6. michael pierzga
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    michael pierzga Senior Member

    Not sure what im looking at. The boat has a keel sump ? The keel bolt is located in this sump ?

    If so this sump is a heavily reinforced structure. Is it ? Can reinforcment be added inside ?

    On the last Hunter repair..a 30 something footer, we left the keel inplace, removed the keel bolt nuts, prepared the surface with a grinder and a course wire wheel brush..

    Built a full length backing plate made of glassfiber set in epoxy on the workbench... Fit this backing plate over the keel bolts set in thickened epoxy then tabbed this backing plate in with several layers of 45 45 biax cloth. Backing plate tabbed to the inside walls of the keel sump. The tabbing extended all the way up to the turn in the bilge above the keel sump box.

    About a weeks work.

    The boat had run agound and damaged the area under the keel bolts
     
  7. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    That keel looks to have taken a good hard shot or two and should be suspect for bent or broken bolts and laminate.

    You can do as Michael suggests and reinforce the inside, where the bolt land, though often you don't have a lot of room to bulk up the area.

    If you want to just splash it for the remaining season, tighten all the boats to spec and just fill the outside with bog and paint. You'll still have the problem, but the bog and tightened bolts may postpone, what's going to be an obvious issue in the future. Ultimately, you'll have to remove the ballast nuts, grind the inside laminate back, build up new laminate around the bolts, grind out the exterior cracked and busted up laminate, re-bed the ballast, then torque up the bolts, fair the seam and paint again.
     
  8. MikeJohns
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    MikeJohns Senior Member

    See the attached image.
    This is probably just the fairing compound around the the sump moulding which is likely to be just a low strength epoxy filler mix. It probably cracks because the keel/hull join flexes a bit. Looks like the main problem is sealing the cracks and any gaps to keep the water out. Keel bolts don't go through that part.

    The others can carry on with their good advice armed with this detail.......
     

    Attached Files:

  9. michael pierzga
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    michael pierzga Senior Member

    Ive never seen a keel attachment like this.

    Hmm

    Water could be trapped in the hull liner and weeping thru the bog into the keel sump box
     
  10. michael pierzga
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    michael pierzga Senior Member

    Is the hull core made with Coremat . Pinkish in colour
     
  11. Goingdef
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    Goingdef Junior Member

    So what would be the best thing to patch this with epoxy and glass fill or fiberglass resin with glass fill? I want to say only one can be used but for the life of me don't remember which,
     
  12. Goingdef
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    Goingdef Junior Member

    I believe so.
     
  13. Goingdef
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    Goingdef Junior Member

    Well these help a TON now I know what seems like an endless caulk joint is actually the bed of epoxy the keel was set in. And the area I'm looking at inset in the keel is actually part of the hull. So should I use an epoxy to re seal the bed and glass mat to bring the layup to the height of the keel?
     
  14. Goingdef
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    Goingdef Junior Member

    [​IMG][​IMG]

    Here's where we are, is this material acceptable to begin repair or is there something else I should do?



    Also to everyone helping I greatly appreciate all your effort in walking me through this, as I realize I'm far from experienced in the field of marine repair but thankfully I'm mechanically inclined so a little more studying and I'm feeling confident I can fix this mess!
     

  15. Goingdef
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    Goingdef Junior Member

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