Keel Bolt / Stud Leaking

[Paul J. Nolan]

Back in the day all keel bolts were bronze, though I suppose in prehistory iron bolts may have been used on iron keels. A long time ago I read somewhere the reason why stainless steel was never used in that application, but have long since forgotten it. I'd appreciate it if someone knowledgeable about the subject would comment.

Paul

[Paws]

Harry:

This thread has spiked my interest as something just isn't right. I look at the pictures and, well, I don't see it.

How much water are we talking about?

I'm assuming this is a deck stepped mast - please correct if wrong.

If the boat just sat in the slip for a week are we talking a sheet of paper towel will take care of it or are the bilge pumps running?

If you went sailing in 15-20 knots and a moderate chop for 4 hours - paper towel, bilge pumps or somewhere in-between?

Have you grounded the boat?

Just trying to help.

John

[Harry Brown]

Boat has not been grounded. It is a keel stepped Mast.
A 5 hour sail, in very calm conditions, produced about a quart of water in the bilge, maybe less.
Standing still in the slip produces no water at all.
I have caught the beginning on the leak thankfully!

[oldvarnish]

I've just had the keel removed from my Victoria 38 in the UK (Morris 38 hull in the US)

You can read about it here from post 718 - it was written by the guy who did it.


What lessons for this week - Page 5

[Kenomac]

Originally Posted by Paws

Harry:

This thread has spiked my interest as something just isn't right. I look at the pictures and, well, I don't see it.

How much water are we talking about?

I'm assuming this is a deck stepped mast - please correct if wrong.

If the boat just sat in the slip for a week are we talking a sheet of paper towel will take care of it or are the bilge pumps running?

If you went sailing in 15-20 knots and a moderate chop for 4 hours - paper towel, bilge pumps or somewhere in-between?

Have you grounded the boat?

Just trying to help.

John

It doesn't matter how much water is coming in, the bigger concern is corrosion of the bolts due to salt water intrusion.

[ontherocks83]

Originally Posted by Kenomac

It doesn't matter how much water is coming in, the bigger concern is corrosion of the bolts due to salt water intrusion.

Ding ding ding!^^^^^^^

It's what you cant see that would scare me. Here is an example of how the threads in the boat look great but let it go with out a proper repair and this may happen.

[Harry Brown]

Well, the picture above doesn't help! ;-)
Especially after I have had this response from Bavaria confirming my questions about the 360 torque setting and the sealant/compound to use, this was the response. I have also attached a link to the Installation Manual below

https://drive.google.com/file/d/0B0T...ew?usp=sharing

"It is 360 Newton Meters (Nm). Yes the right sealant is Plexus MA 310 (incl. Metallprimer).
Attached you find a Manual to install a keel which I found in our data base.
If there is one bolt leaky only normally it is enough to loose the bolt, clean it, grind the laminate around the bolt and make it tight with Sikaflex, Epoxy or Plexus."

So, they seem to think if it is just one bolt leaking, and I assume because of the age of the boat (2007), I'm good to clean and reseal.

I'm sure some people aren't going to be happy about this!
Thoughts?.....

[monte]

Interesting problem Harry. I wonder do they mean the perimeter of the keel is also sealed with plexus, or just the keel bolts? I also wonder if having a watertight void between the keel and hull is necessary or normal. I would think it's preferable but what do the experts say...are they usually watertight or do you often see weeping from the join when hauling ? Miranet's idea of holesawing around the bolt seems like the most effective/non obtrusive fix and maybe reseal with a more flexible sealant.

[ontherocks83]

maybe it's my inexperience with removing keels (read none) but it is weird to me to not see a keel stub.

[Charlie]

I had a similar problem on my boat. It is a 1981. I also had a smile on the front of the keel to hull joint. The boat had been on the hard for months and was weeping water from the bilge. I ended cleaning the smile out with a hacksaw blade and then blew it out. Afterwards I used acetone from a spray bottle to clean out any residual dust. From there I packed it with thickened epoxy.

This part applies more directly to your problem. Maine Sail recommended this method of sealing the keel hull joint. Carve a channel all the way around the joint. I went at least 1/4" deep and wide (though some places it was more) I filled the channel with a sika flex product known for high elasticity though I don't remember the number. I then removed and torqued thee keel bolts and bed them in sika. Since then I have had a dry bilge. This included sailing in 40 + knots of wind with choppy seas. My boat has stout bolts for its size so I wasn't too worried.

[Muckle Flugga]

Originally Posted by neilpride

There is no shortcuts , so your only option come from drop the keel, inspect and check the whole set of keelbolts, clean and remove the old caulking, clean both faces , top of the keel and hull , the best stuff used this days to seal the joint is 5200 from 3M ,, and ask Bavaria for the keel bolts torque when you are ready to tight the keelbolts ,,, others i presume can say that with just a retorque in the aft keel bolt is ok,,,, if you got a leak in the aft keel bolt the joint is compromised...

Without any doubt. 100% agree.

[minaret]

Originally Posted by monte

Interesting problem Harry. I wonder do they mean the perimeter of the keel is also sealed with plexus, or just the keel bolts? I also wonder if having a watertight void between the keel and hull is necessary or normal. I would think it's preferable but what do the experts say...are they usually watertight or do you often see weeping from the join when hauling ? Miranet's idea of holesawing around the bolt seems like the most effective/non obtrusive fix and maybe reseal with a more flexible sealant.

Have done it many times before. For keels with no stub (usually a recess instead) and bonded on, the only way you can drop the keel is to hole saw around every bolt and then hammer thin steel wedges into the joint until it pops. The "deep socket" version of a hole saw works wonders, usually doesn't even need to be that long.

[neilpride]

If you seal , fix the leak at the bolt inside, you stop the leak at the bilge, ok, but how you fix the leak at the hull keel joint? caulquing the joint at the exterior, or injecting plexus at the joint my guess... i mean your biggest worry is corrosion at the aft keel stud by seawater intrusion, and trust me , that bolt is not cosmetic in any way.. you need to check how wide and deep is the gap at the aft trailing edge of the keel, by travelift i think... you need to be sure the keel is firmly attached to the hull, if by chance with the boat resting in the chocks , jackstands ,you try to retorque the bolt and you found it tight in first instance or you reach the torque setting by Bavaria without much effort i will very cautious if the gap still is open with the boat in the travelift, stud elongation, a quart of seawater in calm conditions is to much in my eyes, just my opinion,, be sure the keel hull joint is solid and healty...

[minaret]

Originally Posted by Muckle Flugga

Without any doubt. 100% agree.

For the record, in this instance I probably don't agree (hard to say for sure without being there in the flesh). Removing this keel would probably cause more damage than is there now. Should be an easy fix without going that route.


Also for the record, 5200 is Of the Devil, and should never ever be used unless you are putting two pieces of wood together you don't want to ever come apart; it's an adhesive not a sealant IMHO. 4000UV and 4200 don't have enough open time for keels IME. I like to use Sikaflex LOT (long open time) for keels. Works great, zero failures, loads of open time, easy cleanup, and you can still remove the keel down the road without too much trouble. NEVER bed a keel in 5200! Unless you want someone down the road to curse your name...

[minaret]

Originally Posted by neilpride

If you seal , fix the leak at the bolt inside, you stop the leak at the bilge, ok, but how you fix the leak at the hull keel joint? caulquing the joint at the exterior, or injecting plexus at the joint my guess... i mean your biggest worry is corrosion at the aft keel stud by seawater intrusion, and trust me , that bolt is not cosmetic in any way.. you need to check how wide and deep is the gap at the aft trailing edge of the keel, by travelift i think... you need to be sure the keel is firmly attached to the hull, if by chance with the boat resting in the chocks , jackstands ,you try to retorque the bolt and you found it tight in first instance or you reach the torque setting by Bavaria without much effort i will very cautious if the gap still is open with the boat in the travelift, stud elongation, a quart of seawater in calm conditions is to much in my eyes, just my opinion,, be sure the keel hull joint is solid and healty...

You run the hole saw till it hits steel.



Pretty often I finish a job like this with an exterior tape on the keel/hull joint as well.