Keel bolt nightmare

[hd002e]

After a few years of pondering I have finally built up the courage to have a go at my keel bolts of my beneteau first 305. I have strong reason to believe they are the original.

I have taken out the floorboards to provide good access to the floor. The boat is getting hauled out tomorrow. I will have to tackle the job by myself and I can use all the advice I can get from the forum.

The original bolts seem to have been encased in some kind of epoxy. I have probed around with a screwdriver and things seek to be falling apart without much material left. I will have to get this done without dropping the keel as I have no means of building a keel support for this job.

I expect the first question I will receive will be “why I didn’t get this done before?” When I hd the survey done on the boat ~8 years ago, I was told that they may look rusty on top but underneath it may not be so bad. I had a qualified yard look at it again 5 years ago and they told me it should be OK for a while. Now, I am halfway around the world where I cannot professionally get it done and I am afraid that the keel is going to snap on me at some point.

I will have the photos speak for themselves.

[two-rocks]

Oops - you were told ‘ok for now’ and went half way around the world?

Must be a fast half way - because now was then.

I thought the first series used lead keels? Then why are the bolts not 316 like a good production boat builder uses?

Good luck, I have no advise. Sorry.

[gonesail]

so they look like SS lag bolts? apparently Catalina uses them on their keels. make sure you have a huge breaker bar and hope the heads don't strip or break off

[Cheechako]

Originally Posted by gonesail

so they look like SS lag bolts? apparently Catalina uses them on their keels. make sure you have a huge breaker bar and hope the heads don't strip or break off

Why do you think they are lags? and SS? Just curious...

[hd002e]

The bolts are mild steel and not stainless. The keel is iron. When I called up Beneteau, they sent me A4 70 bolts as replacement, which I believe are 316 stainless.

[Pete7]

The first thing to do is get an angle grinder with a wire brush attachment and clean up the rust around the bolts, nuts and backing plates so you can see what is going on and give yourself a change to get the right sized socket on the nuts.

Also were is the water coming from, the bilge looks wet.

Pete

[Pete7]

Originally Posted by two-rocks

Oops - you were told ‘ok for now’ and went half way around the world?

Must be a fast half way - because now was then.

I thought the first series used lead keels? Then why are the bolts not 316 like a good production boat builder uses?

Good luck, I have no advise. Sorry.

Why would you use stainless steel bolts in to cast iron? for reference mine are mild steel into cast iron. A little surface rust on the nuts and tops of the bolts but that is after 32 years.

Pete

[Cheechako]

Originally Posted by Pete7

The first thing to do is get an angle grinder with a wire brush attachment and clean up the rust around the bolts, nuts and backing plates so you can see what is going on and give yourself a change to get the right sized socket on the nuts.

Also were is the water coming from, the bilge looks wet.

Pete

Yes, do this. Once you screw those heads up you're in trouble.
-Use a 6 point socket.
-If I were doing it I would use an air wrench that hammers, like a lug nut air wrench. Well worth the rental price if it avoids breaking!
-That hammering will break things free much better than just force which may snap it off. Especially if you don't put the hammer torque on full.

I would put Lanolin on the threads of the new bolts.

[kenbo]

I believe that you'll be incredibly fortunate if you are able to remove those bolts without dropping the keel.

But the first step would be to start soaking them with something like PB Balster, Kroil or ATF with Marvel Mystery Oil. Do this for days. I'd also drill a small hole(s) at a 45° to the bolt to make sure the penetrating oil is getting below the surface of the bolt shoulder. If you have some controllable heat source I'd apply that as well. Tapping the head of the bolt with a hammer occasionally will maybe break some of the corrosion bond.

Make sure you have a well fitting socket, 3/4" drive if you have it and give it a go with with as much steady leverage as you can apply.

If you do get them out clean the threads in the keel as best you can, vacuum and a long tube cleaning brush may help. I'm sure you won't have the correct tap to chase the threads but if you can find a steel bolt with the same threads run that down a few times to help clear things out.

Install the A4 bolts with Never Seize or similar to prevent galling of the SS bolt threads.

Good luck!

[kenbo]

The 6 point socket is a great mention as is the impact driver if available.

How many keel bolts do you have? And have you considered how many you would need to replace to feel secure getting to a facility where the keel could be dropped and the repair done properly?

[donradcliffe]

I watched this project being done on a sistership in a yard in Thailand. First, they removed the bolts and lifted the hull off the keel. Then they took the keel off to a machine shop and cleaned up the threaded holes in the cast iron. Then they reassembled it with all thread rods sticking out of the keel and regular nuts on the inside (you can torque the nuts much more safely than the bolts into the cast iron. When they assembled it, they first put a separating agent on the bottom of the hull and the holes in the hull, then put a layer of epoxy putty on the top of the keel and dropped the hull on overnight. The next day, they separated the hull and keel, cleaned up the epoxy edges, and put a layer of 5200 in and reassembled. Finally, a week later, they torqued the nuts. When they were done, the boat was better than new, and could have gone round the world.

Based on their experience, you may very well find that the threads in the cast iron will be corroded and stripped and the job isn't as simple as putting in new bolts. I didn't see the first disassembly, but they may have tried new bolts and couldn't get them to torque up without stripping out.

[Allied39]

I am going to address one point only.
Building a support for a keel is incredibly easy and requires very few tools.
A hand held circular saw and a cordless drill.
Materials are some 6x2 and 3x2 timbers. Dry wall screws.
The most important thing to remember in designing keel cradle is that you are simply maintaining it in an upright position. You do not have to support it in a 45 degree angle. All weight (force) is straight down.
Two or three or three or four 6x2 flat on the ground depending on dimensions. uprights atatched to the 6x2 and gusseted with 3x2 timbers as needed
Incredibly simple (almost childlike in simplicity) and almost free, especially in comparison to the other expenses you are about to incur.
Have fun!

[sandy stone]

I think all this talk of dropping and rebedding the keel is getting way ahead of the game, unless you know already that water is coming into the boat around the keel bolts. I think that is actually pretty unlikely. Also, I doubt seriously that new keel bolts that you got directly from Beneteau are stainless steel; they are normally high-tensile mild steel for compatibility with the cast iron keel. I have a boat of the same era and construction and my keel bolts look better than yours, but I have seen some that looked much worse and the keel was still on the boat.

I would start with the easiest to access bolt and try the techniques described above - soak with plenty of penetrating oil (Kroil works well for me), wait a while, and use the biggest impact wrench that fits into the space. Your experience with that bolt will give you some idea of what you are getting into. There is no particular reason to haul the boat for this job, if you can replace the bolts one at a time, unless the worst happens and you see water seeping in from a keel bolt hole. Then you probably are looking at rebedding, but I do think it's unlikely.

After replacing the bolts, you should paint them with some kind of primer like Rust-Oleum, especially if you intend to live with water in your bilge. Good luck and please let us know how it goes.

[svHyLyte]

Originally Posted by hd002e

The bolts are mild steel and not stainless. The keel is iron. When I called up Beneteau, they sent me A4 70 bolts as replacement, which I believe are 316 stainless.

A. The bolts are high strength steel not stainless;

B. The bolts are "Dacrotized", i.e. coated with a finish similar to galvanizing but thinner, smoother, stronger and more long lasting which is a European industry standard.

C. The look of your keel bolts is about what one would expect given their age. Note, however, that "rust" is about 600% greater than the volume of steel that has "rusted" or oxidized so looks are deceiving and not an indicator of the condition of the underlying bolt heads. The rust can be wire brushed off, if necessary the sides of the bolt heads can be ground somewhat to get flat surfaces that will accept a socket and they can be unscrewed. Ninety-nine point nine percent of the time they will come out clean and dry in which case the seal between the keel and the keelson is intact. Note that the bolts are torqued to about 150 lbs-ft so loosening them takes some effort, preferably a long "breaker bar". The new bolts should be inserted through new square washers with a modest amount of sealant on the 1/2" or so of the bolts above the threads--Not On The Threads! Once in place a torqued, cover the bolts and washers with a glob of wax from a toilet seal. That replaces the epoxy sealant that Beneteau used in the original build but will last longer as it isn't brittle but can easily be removed if one wishes to inspect the bolts at some future date.

D. BeneteauUSA has a technical bulletin on the replacement of the keel bolts which can be done, one-by-one, in a star patterns, with the boat in the water without difficulty. You can contact Ward Richardson at BeneteauUSA for a copy of the bulletin or PM me and I will email you a copy.

E. This subject has been discussed on the forum frequently. Do a search (above, right) on "Beneteau Keel Bolts" for the various discussions. The job isn't hard, just tedious


FWIW...

[hd002e]

Originally Posted by Pete7

The first thing to do is get an angle grinder with a wire brush attachment and clean up the rust around the bolts, nuts and backing plates so you can see what is going on and give yourself a change to get the right sized socket on the nuts.

Also were is the water coming from, the bilge looks wet.

Pete

I will start doing that as soon as I am out on the hard. The moisture is from the acetone+ATF I am brushing on there in hopes of freeing it up before I give it a go.