Old Keel bolt repair

alanr77 · #1 (**permalink**) 08-07-2011

As I am preparing the boat for her trip to a marina for haul out and refit this winter, I am making a list of all the fun things I have to do to her this year. I pretty much have a plan for how I will do everything except for the following;

I have read countless articles on how to repair the keel bolts on a Catalina 30. I understand how to cut out the floor, remove the wood and install a plate to prevent the "smile". However, when inspecting the keel bolts, I am confused as to what action is required to repair my bolts. I have never seen anything like what is on my bolts. It almost looks like someone put welding slag on the bolts. I can't even begin to see how I will put a socket on these. Take a look at the pictures, any idea's?

Catalina 30 tech pictures by alanr77 - Photobucket

deniseO30 · #2 (**permalink**) 08-07-2011

Looks like an extreme example of rusty stainless! Scary! How about a hole saw the size of the bolt and just saw the the nuts off? Hole saw may not be deep enough so the bolt ends would have to be shortened..

LakeSuperiorGeezer · #3 (**permalink**) 08-07-2011

I would get a Dremel cut-off wheel with appropriate mandrel for a size that fits the center hole in the cut-off wheel. The Dremel 456 1-1/2" fiberglass reinforced wheel is an example. It's small enough to get into a tight space and with enough time you can cut through a good size bolt. I would cut the bolt flush and try driving the bolt out with a punch. If that does not work, try drilling it out. First start with a pilot drill of about 1/8 inch and then follow with a 5/16 inch and then whatever the original bolt size. You could also try dissolving the rust with muriatic acid diluted ten to one. You could replace the keel bolts with silicon bronze. Even galvanized works better that stainless for keel bolts because stainless has about the same corrosion resistance as an ordinary steel bolt in an anaerobic environment where air cannot get to the stainless to create the protective coating.

mitiempo · #4 (**permalink**) 08-07-2011

They have to be replaced - cut the nuts off and drop the keel. The big problem is replacing them as they can't just be unwound from the keel due to their shape.

alanr77 · #5 (**permalink**) 08-08-2011

Great...just what I didn't want to hear. I don't feel that I can drop the keel off this boat. That is a huge undertaking that costs far more than the boat is worth. Am I wrong? If I understand correctly, the keel bolts- iron not stainless in a 1976- are installed when the keel is cast. There has to be another way. The boat currently does not show any signs of the C smile. There is no water leaking. Maybe when the boat is pulled next month and I chisel off the rusted mess on the bolts I will be able to see some sort of threads that I can work with. In addition, maybe when I cut off the top layer of fiberglass to replace the wood I will find decent threads. Just trying to be optimistic. I may have to call Catalina and send them some pictures to see what they suggest. Maybe I am making the cost of replacing the bolts bigger than it actually is. And the story continues.......

TQA · #6 (**permalink**) 08-08-2011

Dat NOT good. Dem bolts dey done mon. When exactly they will fail who knows but it looks sooner rather than later to me. You could attack them with a needle gun to see how much good metal is left and paint it if there is some.

If your conscience allows Ebay it for what you can get.

As for removing the keel an expert user with a gas axe and a little custom made thin steel protection could cut through those bolts in a couple of minute. Fire extinquisher to hand of course. Other wise forget the dremel, a three or 4 inch angle grinder with a cut off disc and just grind of the heads.

alanr77 · #7 (**permalink**) 08-09-2011

Update, Catalina Yachts is amazing. I sent them an email and got a response from an engineer in less than 12 hours. P/N's, diagrams and instructions. All this for a 36 year old boat. I guess thats why they have been in business for so long. Anyway, next month I am going to cut away the wood and fiberglass above the keel. Hopefully there are some threads remaining under the mess in the pictures. I will then install 7 12" lag bolts into the keel with stainless steel plates with washers as support. I figure between the original bond between the keel and the hull, the remaining holding force of the original bolts plus the added lag bolts, I should be fine. Having spent a few hours researching this subject, I don't think there has been any documented cases of a C-30 keel falling off. This is somewhat comforting as I was really upset about the serious setback with this boat. Now that I have a plan I guess we will see how it turns out. I will take lots of pictures and video of the keel bolt repair, keel stub wood removal and keel crack repair. I will then save this in a file that I can share with anyone dealing with the same issues.

mitiempo · #8 (**permalink**) 08-09-2011

After you cut out the wood build up the glass in thickness with roving or biaxial, going well up the sides of the keel stub for added strength - to replace the strength that was supposed to be created by the wood layer originally.

CatalinaRob · #9 (**permalink**) 08-09-2011

check out this link for details on this repair:

The famous

SloopJonB · #10 (**permalink**) 08-09-2011

There is a recent discussion of this process in the "General" forum under "Morgan 35...."

Those photos look like you have rusted steel bolts bursting from under resin encapsulation. If that is the case, do you have an iron keel?

An iron keel makes it a pretty simple, albeit big job to replace the bolts. Properly replacing the bolts in an iron keel is a much better way to go than sistering and it is very do-able by oneself - I did it on a 10,000 lb. keel (with help from heavy equipment of course). You are then back to new, not just patched up.

Check out the thread I referred to and get back here with any comments or questions