Do you know your keel bolt details

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BurnitBlue

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I bought a Moody 346 a few month ago. I have previously been a long, encapsulated keel type yacht owner. I was surprised that there is virtually no information on the keel bolts on this yacht from either the designer or the MOA.

Asking around the marinas here I was amazed that I couldn't find one person with a bolt on keel who knew the dimensions of his keel bolts.

Is this information not important? Don't skippers care if there keels are held on with tooth-picks?

How many on this forum know the dimension and nymber of their keel bolts and whether they are adequate for the job. How much wastage is OK for instance.

I am seriously considering getting rid of this bolt on keel boat and returning to encapsulated for my next boat.
 
I think they are M24 mild steel. Whilst there are several threads and articles on the MOA website about checking and replacing of keel bolts I have never read of any keels dropping off or this being of concern.

If you have concerns then a surveyor should allay them. Join the MOA for £20 and enjoy the fruits of other's experience.
 
Can't remember exactly how many I have ?8. I took some out when I got the boat and they were fine. I replaced the ones I took out and I can't tell you what size they were but hefty is an appropriate word. A bit bigger than my thumb in diameter. The boat is 50 years old and they seemed in good order so I can't say I am worried. I wouldn't take it into the open sea until I had checked, however.
 
I changed the ones on my Seawolf 26 because the nuts and the exposed part of the studs had rusted badly. There are eight mild steel studs. I think they were 1" but they may have been 24mm.
 
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How many Moody 346s have lost their keel? How many fin keels have fallen off yachts this year? Statistically your worries are groundless, but if you need something to do why not pull them out and replace them. You can count them while you are doing it.
 
BlueTwo said:
How many on this forum know the dimension and nymber of their keel bolts and whether they are adequate for the job. How much wastage is OK for instance.
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I don't understand your point?

Yes, I know their diameter and how many, and am happy they are adequate for purpose based on common sense and reported experience of the same type of boat over many years.

Why is knowing the 'acceptable wastage' interesting?. I don't know of any owner of an AWB who routinely (ever) withdraws keel bolts to inspect them (I even question if this is practical without dropping the keel(s).)

Vic
 
Bwahahahahahaha!!!!!!!!!!!!!!!!

I have a complete spare set on board, with nuts and washers.

You never know.......
 
Moody keel bolts are a well worn topic. They are mild steel, either 20 or 24mm diameter. They rust at the top because most older Moodys leak through windows and deck fittings, so the bilges are wet. However, once you clear all the crud off there is nothing wrong with the threads or the integrity of the fastening. You might ask Richard1002 about his experience of having drawn a sample - only to find they were perfect.

Moody keels are very secure, so spend some time cleaning them up and repainting - if the nuts or backing plates are badly corroded replace them. Then try and cure all the leaks so that you don't have wet bilges. Also double check the keel hull joint that there is no leakage there - highly unlikely.
 
I know exactly what I have on my boat. None at all the keel is welded to the rest of the boat. At least I know it isnt going to fall off!
 
owen-cox said:
I know exactly what I have on my boat. None at all the keel is welded to the rest of the boat. At least I know it isnt going to fall off!
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The keel falling off Drum England was due to weld failure
The keel failure of the 33' yacht off Falmouth a few years ago was due to weld failure

To the original post:
I understand that the designer of a boat will specify the number, diameter and spacing of the keel bolts and the details of the keel pan/hull-keel joint so that the whole hull-keel system can adequately handle the loads, including B1 and B2 knockdowns (B1 = 90 - 120degree, B2 full 360 roll: check the '79 fastnet disaster report).

EU CE requirements for leisure craft place requirements on the builder to get this right and for racing yachts, adherence to ABS (American Bureau of Shipping) scantlings or Lloyds calssification ensures that a qualified structural engineer signs off the design details, including materials and build method.

I am interpreting your concern is knowing how much reduction in bolt diameter due to corrosion can be allowed, before you have to do something about it. For this, typically the answer is none, and as some of the posts above allude, it is very rare that there is significant corrosion of keel bolts, unless some other factor has come into play:
damage due to grounding
moisture getting into the joint

If you hit the ground hard, normally there a a lot of other signs before the keel bolts snap and usually the front or back of the keel pan gets shattered. In these cases, then the insurance company's surveyor will usually aks for the keel to be removed so that the bolts can be checked and replaced

If there is a moisture in the joint, you usually see the tell tale signs

Not a reason for getting rid of your boat. Try the Moody owners forum for more specific info on keel bolt weakness on the 346 but I suspect your fears are unfounded
 
BlueTwo said:
I bought a Moody 346 a few month ago. I have previously been a long, encapsulated keel type yacht owner. I was surprised that there is virtually no information on the keel bolts on this yacht from either the designer or the MOA.

Asking around the marinas here I was amazed that I couldn't find one person with a bolt on keel who knew the dimensions of his keel bolts.

Is this information not important? Don't skippers care if there keels are held on with tooth-picks?

How many on this forum know the dimension and nymber of their keel bolts and whether they are adequate for the job. How much wastage is OK for instance.

I am seriously considering getting rid of this bolt on keel boat and returning to encapsulated for my next boat.
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Yes, I do.

When we bought our Moody, the surveyor asked for one to be drawn (long story why but not relevant here). M24 Mild steel about 8-10" long (sorry for the mix in units) - in 1999 it was perfect and I have no concerns that it has changed since. They are quite straightforward to get out and if I was as worried as you seem to be, I would do that when next ashore.

Windows can contribute to water in the bilge (although mine don't leak) nor in my case is it leaking deck fittings - the fridge drains into the bilge and the pressure spill off from the calorifier did - now fixed! We also get water in the bilge when fitting/removing the speed transducer each week.

Hope that allays your worries a bit.

As said previously, the MOA is a fantastic place for these sort of queries and at £20 isn't too expensive.

Piddy
 
Tranona said:
Moody keel bolts are a well worn topic. They are mild steel, either 20 or 24mm diameter. They rust at the top because most older Moodys leak through windows and deck fittings, so the bilges are wet. However, once you clear all the crud off there is nothing wrong with the threads or the integrity of the fastening. You might ask Richard1002 about his experience of having drawn a sample - only to find they were perfect.

Moody keels are very secure, so spend some time cleaning them up and repainting - if the nuts or backing plates are badly corroded replace them. Then try and cure all the leaks so that you don't have wet bilges. Also double check the keel hull joint that there is no leakage there - highly unlikely.
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Hi....

In 2009 I was ill in the UK and Rogue, (Moody 44), was in Malta. I had arranged for the boat to be lifted and anti fouled by Boatcare of my Marina, (Portomaso). On lifting, they sent me some hull photos and said the keel was misaligned. This would require them to drop the keel etc. Involving many thousands of euros of work.

I didn't believe them, so arranged for a hull survey by John Ross. He confirmed that the keel was fine, but commented on the external condition of the keel bolts - very rusty and corroded where visible in the bilge. He recommended replacement.

I jetted off to Malta, arranged for the bolts to be replaced, (and anti fouled the hull).

Once they got the 13 bolts out, it was quite clear that the corrosion was fairly superficial, and the invisible parts of the bolts, (behind the nuts and in the hull), were all as sound as the day they were fitted 14 years earlier.

Having said that, as I was selling, and a buyers surveyor would probably make a big deal of the keel bolts, I decided to spend a few hundred euros on having new ones fitted. I'd probably saved the cost by doing my own antifouling :)

As has been said - keel bolts on Moody's cause a lot of concern...... But I couldn't find anyone who had drawn any and found a problem.

I was tempted to keep the old ones and clean them up, just in case...... Eventually decided they were pretty heavy, and cluttered the place up, o I chucked them.

I wouldn't worry about your keel bolts. I had a plan that I never got around to.... This was to clean them up, seal some toilet hose around each one to keep the water out, and fill them with grease.

As it happened, my buyers surveyor still made a negative comment on them - even though I was there to show him the bill from 8 months earlier!! So I think it was money well spent.

Saw Rogue in Liverpool in July, and her keel still hadn't fallen off :)
 
Thanks a million for all the replies that reassured me that I had nothing to worry about.

I guess my main concern was that I know very little about bolt on keels and their bolts and from the replies around the marina it was beginning to look like I would never know.

I am a member of MOA and the keel bolts on my 346 were replaced 5 years ago and I was wondering if this was a regular maintenance chore like rigging replacement. The keel bolts were replaced on the advice of a surveyer for an insurance survey. He also recommended changing the standing rigging at the same time so I thought they were linked.

So. Nothing to worry about. Thanks.
 
BlueTwo said:
Thanks a million for all the replies that reassured me that I had nothing to worry about.

I guess my main concern was that I know very little about bolt on keels and their bolts and from the replies around the marina it was beginning to look like I would never know.

I am a member of MOA and the keel bolts on my 346 were replaced 5 years ago and I was wondering if this was a regular maintenance chore like rigging replacement. The keel bolts were replaced on the advice of a surveyer for an insurance survey. He also recommended changing the standing rigging at the same time so I thought they were linked.

So. Nothing to worry about. Thanks.
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I think I'd rather stick with originals rather than worry about the new ones being fitted correctly and the joint didn't leak
 
Tranona said:
Moody keel bolts are a well worn topic. They are mild steel, either 20 or 24mm diameter. They rust at the top because most older Moodys leak through windows and deck fittings, so the bilges are wet. However, once you clear all the crud off there is nothing wrong with the threads or the integrity of the fastening. You might ask Richard1002 about his experience of having drawn a sample - only to find they were perfect.

Moody keels are very secure, so spend some time cleaning them up and repainting - if the nuts or backing plates are badly corroded replace them. Then try and cure all the leaks so that you don't have wet bilges. Also double check the keel hull joint that there is no leakage there - highly unlikely.
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Agree with the above. I replaced the keel studs and backing plates on our 346 twin keeler. All were 24mm and below the nuts in excellent condition. However, the nuts had rusted and flaked to a couple of sizes smaller. Found the easiest way to slacken was with a combination spanner (ring end) and lump hammer! All studs came out complete with nuts rusted on. Got 1m lengths of threaded rod and nuts from Bearing Man.
 
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