Keel to hull joint

[Geoffreykwright]

The hull-joint caulking on my 2000 Cat 34 Mk II (Hull 1494) seems brittle.  There are only a couple of spider cracks in the caulking - so it still looks sound - but seems to be getting brittle.  Is removing the caulking and re-caulking with something like Sikaflex 291 the way to go?  Is this easy to do?

Thanks in advance.

[not_yoda]

curious to see who else has seen this...  have my boat on the hard redoing the expoy bottom...  it looks like i'm not the first one to "fix" this crack, etc...  any thoughts on what i should do or how i should handle it?

thanks in advance!

[Jeff Kaplan]

My '86 has the same crack every year, the Catalina smile. Sometimes the crack is straighter, sometimes it looks like yours.  Each spring, I sand down both sides, usually take a philips screwdriver and open up the area slightly and fill with a 2 part water tite filler. I never get a leak into the bildge, nor does the smile get any longer or wider, just a yearly maintance issue.  I had a C27 years ago and it had the same issue. Good luck.

[waughoo]

I would also add torquing your keel bolts to the list of to dos.  I found my forward most bolt to be quite loose (1 full rotation) when I had a similar crack.

[scgunner]

That's the much storied "Catalina Smile", there are a number of ways to skin this particular cat. How you handle it depends on how much it bothers you. It's mainly a cosmetic issue that's common with these boats. As you can see it's been fixed before and looks ready to get fixed again, think of it as one of the things on your to do list when you pull the boat out for bottom paint.

What I do with my smile is when I haul out I open it up, clean it up and let it dry out for a day or two. Next I fill it with West Systems epoxy, sand it smooth, prime and paint and it's good to go until the next haul out when the process is repeated.

[DaveBMusik]

Older boats used plywood between the bilge floor and hull through which the keel bolts pass. I'm not sure when they stopped using wood. Any water leaking in through the crack can deteriorate the wood and potentially the keel bolts.
After digging out the compromised wood and building back up with glass, I dropped my keel, inspected the bolts, rebedded with 5200 and glassed the seam. No issues after 5 years.
FYI, the bolts looked new.

[Geoffreykwright]

My bolts are good - its just the caulking getting brittle.  and my 'smile' is not as advanced as the images posted.  I am guessing I should remove the old and replace with new versus putting a new layer of caulk over the old?

[Ron Hill]

Not : I assume that you have a wing keel??

A thought

[Geoffreykwright]

Ron - yep - wing keel.  I've seen the 'traditional' Catalina smile and this is not what I have - just some mild cracking in the caulk.  Best thing to do would (I think) would be to remove all the caulk and re-caulk - but wondering if I might get away with a fresh layer of Sikaflex 291 on top of the old layer to get me thru the season.  I've got a lot of work to do and just under 3 weeks to launch.