Keel Nut Removal in the Water

[waterdancer]

Hi folks
On my C&C 25 the lower washers under one keel bolt are totally rusted out. It is literally in crumbles in the bilge. (There were 2, the upper one seems fine)
So there is a large gap where the washer was. So the nut/upper washer is sitting on this crumbled piece of rust at about 1/4 of the area. That is what is left from the lower washer.

I would like to take the nut off, scrape away the rusty washer, put on a bed oh 5200 and a few new washers and tighten it again.
Just one nut. The boat is currently not taking in any water and has no smile.

Some say I should not do it in the water, many say as long as it is just one, it is no problem
Any words of wisdom ?
Thank You
Ahmet
Boston, Ma

[Stumble]

Absolutely not!

First, if you have a rust problem in your keel bolts you need to drop the keel and find out what's going on, not just replace a bad washer. It may be nothing, but you could be looking at the leading edge of a major problem. There is no way to know without disassembly.

Secondly, if you knew for sure everything else was fine, I still wouldn't do it. Taking off keel bolts places a lot of load on what remains. Likely it would be fine, but depending on which bolts it is, it could also lead to them unzippering. Sure it's highly unlikely, but if you are wrong the boat is now totaled. Just think it thru, if the keel does unzip, the keel immediatly falls off, the boat rolls over (likely breaking the mast), damaging anyone else's boat it touches, then sinks.

Third,

A C&C 25 can probably be lifted by any near by yacht club crane. A simple lift, drop onto a borrowed trailer, then inspection wouldn't take more than a weekend. If you do have a keel bolt problem, then at least you know it's a major issue, and can decide if it's worth it to fix the boat.

[roverhi]

I wouldn't imagine it would be a problem. Not unusual in a flat bilged boat to have the keel bolts live in water. A piece of poor quality stainless, like this washer probably was, would do just what this washer did. The boat has multiple keelbolts to hold the keel in place for the everyday beatings the keel takes sailing and then a big some more as a safety factor. One bolt in the middle would probably suffice to keep the keel attached to the boat sitting in a slip.

Do be prepared for it not to go as easy as you think it will. If the keel bolt is also corroded, you could end up with the bolt breaking off. A close inspection is in order. Wire brush around the base of the bolt to clean it up and inspect. Probably would be a good idea to check all the bolts one at a time. If they look fine, replace the washers and maybe the nuts too and your good to go. If the bolt(s) is/are pitted and reduced in diameter, time to haul the boat, drop the keel and for a bolt replacement, probably all of them.

[neilpride]

The fwd and aft single bolts is a concern if you do it in the water , best with the boat in the hard...

[waterdancer]

The Nuts, visible parts of the bolts and the one washer is in good order.
No way to remove the bolts because it is a lead keel and they are J - bolts.
It seems to have 2 1/2/inch bolts in the outer edges and 2 1 inch bolt in the center. This is one nut in the center. No pitting in the bolts or nuts.

As in all other lists, the opinion seems to be divided.
My cocern is that due to the rust on the lower washer, that particular bolt is really not holding anything.
I was able to "Clean" out the remnants of the lower washer with my finger, and you can see from the picture that the upper washer is pretty much in the air

[Stumble]

The bolt in air is almost never the problem. If there has been enough salt water to destroy the washer then the only thing protecting the entire rest of the bolt thru the hull is whatever sealant was used 30 years ago. If the sealant has let loose at all, then you may have a completely corroded keel bolt with a nice end piece attached.

Below is a nice example of what you may be looking at.

[Adelie]

Another thing to consider is whether the keel bolts are actually bolts or if they are studs.

Studs are embedded into the keel.

If the keel has a flange across the top it may thru bolt thru the flange into the hull. In which case if you pull the nuts off only the sealant will be keeping the bolt from falling out leaving a bolt sized hole for water to get in thru. The Cal 20 is like this and the Ranger 26 or Pearson 26.

[waterdancer]

Originally Posted by Stumble

The bolt in air is almost never the problem. If there has been enough salt water to destroy the washer then the only thing protecting the entire rest of the bolt thru the hull is whatever sealant was used 30 years ago. If the sealant has let loose at all, then you may have a completely corroded keel bolt with a nice end piece attached.

Below is a nice example of what you may be looking at.

Yes that image has been going around the internet quite a bit, explaining crevice corrosion.
There is really not much I can do if I had a problem like that on a $3000 boat. It would probably be indicated by "SMILE", water intrusion etc

[waterdancer]

Originally Posted by Adelie

Another thing to consider is whether the keel bolts are actually bolts or if they are studs.

Studs are embedded into the keel.

If the keel has a flange across the top it may thru bolt thru the flange into the hull. In which case if you pull the nuts off only the sealant will be keeping the bolt from falling out leaving a bolt sized hole for water to get in thru. The Cal 20 is like this and the Ranger 26 or Pearson 26.

Definitely Bolts

[Cheechako]

I see no problem with taking one off at a time.

[chris95040]

Any idea what material the bolts are?

If they are bronze you probably dont have much to worry about, and maybe someone put some stainless washer hardware on there at some point (although, why?)

Otherwise, if stainless, I'd be inclined to start wondering about their condition after this one exhibited this problem. Probably fine, but thats one thing that stinks about j-bolts. Inspection really a pain. Nice that it facilitates retorquing solely from the bilge, though. Which is the bare minimum I'd do here, btw, retorque all the others one by one and make sure they dont snap off in your hand.

[Terra Nova]

The next time you haul the boat do the repair. With the boat supported by the keel, there will be very little movement of the caulked joint to disturb the rest of the seal. Don't take shortcuts where they are unnecessary.

[waterdancer]

Originally Posted by chris95040

Any idea what material the bolts are?

If they are bronze you probably dont have much to worry about, and maybe someone put some stainless washer hardware on there at some point (although, why?)

Otherwise, if stainless, I'd be inclined to start wondering about their condition after this one exhibited this problem. Probably fine, but thats one thing that stinks about j-bolts. Inspection really a pain. Nice that it facilitates retorquing solely from the bilge, though. Which is the bare minimum I'd do here, btw, retorque all the others one by one and make sure they dont snap off in your hand.

They looked galvanized to me. Based ob the hull ID this boat seemse to have been salvaged in 1992. It is highly likely that they put it stainless washers and then galvanized washers with nuts. The Stainless rusted away, tha galvanized stayed.
There was no bilge pump. I installed one, and whatever is left after the bilge pump in the sump, is about one or 2 sponges. So there is no reason in the future for these bolts and nuts to sit in the water.

How can I check what they are. There is no pitting,


Here is another picture.




This picture, (you should be able to zoom in) shows another problem. The keelbolt is hanging off halfway on the sump wall !!!
But the bolt, nut and washer are in good shape. The discoloration is from sitting for years in water that was full of rust.
At some other time, I will glass in the bottom of the bold and make sure that the washer has a good hold.

[waterdancer]

Originally Posted by Terra Nova

The next time you haul the boat do the repair. With the boat supported by the keel, there will be very little movement of the caulked joint to disturb the rest of the seal. Don't take shortcuts where they are unnecessary.

True. I also have the option to careen it against the wall but I don't want to deal with that in the winter.

[chris95040]

On that picture, the top of the bolt looks like shiny bronze, anyone else agree?

If that were all I saw there, I'd say great, verify, replace all washers and nuts with bronze, and retorque.

But that situation there looks worrisome. The nut is sitting on the walls because the shelf underneath it has collapsed, you can see the threads of the bolt peeking through. Is that just a shim piece, or is that part of the hull? It almost looks like possible damage from runnimg aground hard.