Terrifying Keel Bolts !!

[RaymondR]

Originally Posted by jamhass

use a nut breaker:

https://www.amazon.com/CRAFTSMAN-Uni...9407216&sr=8-6

There's seldom enough room in the bilge of a boat to use a nut splitter properly because they generally require horizontal application and hence the drill and cold chisel solution which is applied vertically.

[bil56]

it would still be more reasonable to do this work dry in a shipyard ...
destroy one nut at a time (mini grinder, nut Splitter),
new large backing plates, plates, new steel nuts, paint or other protection (greased cloth strip)
but you also have to be sure that the threaded rods are in good condition ...

[Searles]

It’s a cast iron keel with ,I hope s/s inserts for galv steel or s/s threaded in bolts ,to be changed or at least inspected every ten years ,must be done on the hard for safety , people on the forum will tell you that they have never changed or inspected there threaded in keel bolts ,that doesn’t make it right ,for peace of mind and safety do it right.⚓️⛵️

[capt jgw]

At least the bolts or threaded rod can be replaced cheaply. Probably the only advantage of iron over lead besides initial cost. Lead gets the weight down lower and doesn't rust, but almost always the "J" bolts are cast in and can't be replaced, at least not at a cost that anyone would pay. By the time the boat is old enough to require replacement, the cost to do it could be multiple times the value of the boat.

[boatpoker]

Originally Posted by Searles

It’s a cast iron keel with ,I hope s/s inserts for galv steel or s/s threaded in bolts ,to be changed or at least inspected every ten years ,must be done on the hard for safety , people on the forum will tell you that they have never changed or inspected there threaded in keel bolts ,that doesn’t make it right ,for peace of mind and safety do it right.⚓️⛵️

I've never seen an "insert" in any cast iron keel but I've only closely examined less than 20 when off the boat..

[RaymondR]

It's more likelly that the keel is cast steel than cast iron and that the stud holes were just frilled and tapped in the cast steel (or iron) Mild steel is generally as cast iron which comes out of the ore reduction furnace with a lot of carbon in it. The high carbon content is reduced by blowing oxygen through the molten iron.

[boatpoker]

Originally Posted by RaymondR

It's more likelly that the keel is cast steel than cast iron and that the stud holes were just frilled and tapped in the cast steel (or iron) Mild steel is generally as cast iron which comes out of the ore reduction furnace with a lot of carbon in it. The high carbon content is reduced by blowing oxygen through the molten iron.

It's a 2001 Jeanneau SO 43 DS. It is cast iron.

[Searles]

We have fitted a number of Benny and Juneau cast steel or iron as you will and some Bavaria’s all and I mean all had inserts like helli coils in the keel casting for the bolts supplied some galv steel most 316 s/s ,all these were new vsls ,maybe an Australian thing .⛵️⚓️

[argonauta1]

As far as I know Jeanneau is an operating company with a full after market support capability. Why hoper grope? Go to the source; this problem if it is such should not be new. Incidentally, it might look worse than it is. A good clean up should provide a more accurate picture. Good luck

[Colonel Bob]

This photo doesn't look that much different than the keel nuts and plates on my 42DS. Rust seems to be mostly cosmetic and I had amazing results with a half hours work with power drill and brass wire wheel. I followed up with Derusto, which may or may not be a good idea but they still look great after 18 months.

[gcaws]

Answers.

1. Steel nut material is typically same as keel therefore no dissimilar metal corrosion. This is paramount as your corrosion is visible and not hidden which is much more dangerous. Stainless nuts are weaker and will cause corrosion likely on the threads which is deadly. Ie it looks fine untll all the threads fail and the keel falls off. Generally nut can lose 50% of its weight (as rust it looks much worse as iron oxide expands) and still be fine. Yes the washers will be the first to go.

2. Do not replace the threaded bar. Having done this myself you’ll find it’s in perfect condition for above reasons. If you do, you must match the keel steel. Stainless per above is bound to fail. It is simply dangerous. Don’t be fooled by a little external corrosion as that is a red herring.

3. I would haul to do the work. Safer and no water ingress into bolt holes possible.

- Final Advice - Talk to your factory about replacement. Relying on here-say and social media advice is dangerous and you will not be able to tell uninformed conjecture from fact. The road to hell is paved with good intentions.

[Alita49DS]

The keel bolt nuts and plates on my Jeanneau 49DS also look pretty rusty and the posting reminds me to get them looked at. Sods law of the sea being what it is the boat has just been lifted and splashed!

The point that I would wish to make is that the root cause of this problem is bad design by Jeanneau. Not of the keel fixings. Of the bilge. The boat is nearly flat bottomed and the limber holes are above the hull base. Which itself is not smooth or shaped to flow water into the tiny sump by the bilge pump.

The result is that if there is the slightest leak in the boat a cm or more of water sits in the bottom of the boat. Including and all around the keel fixings. So they end up living a miserable wet existence.

By way of example, even if there is no unintended leak (seacock, shower, whatever) if you take the drain plug out of the fridge the water would simply end up sitting in the bilge.

Maybe the litigous US owners of Jeanneau boats will take out a class action!

[Happ]

Originally Posted by boatpoker

Jeanneau ... Cast iron keel.

I Jeaneau says it’s a cast iron keel that would make sense. The next question is what are the bolts made of? Nuts made of? Most likely the same but, worth the ask. My concern is without dropping the keel you will never know how big of a problem you really have. Is the cast iron keel reacting adversely to the metal of the nuts and bolts? The cost isn’t necessarily going to be cheap but should that be the case an afternoon sail could turn into a rescue for those onboard.

A long time ago there was a known defect in a boat in the design of the keel bolts placement and the stringers. The design was altered to fix the problem. Our boat was 2 boats after the change. We experienced the same problem. So we dropped the keel and discovered a totally different problem. The point is you really don’t know what the problem really is until you really see is causing the problem. That is what you really want to know.

[MicHughV]

A keel bolt usually has a plate, large washer, etc, attached to the bottom of the bolt, so is unlikely to come out. Assume the bolt is embedded 18" or more.

Nonetheless, being a worrywart like me, I'd probably pull the boat to perform any kind of keel work.

[sailorladd]

Looking at your photo, the actual keel bolt looks OK... Can't tell if it's galvanized metal or stainless steel... If it is galvanized, its in very good shape and I would certainly have no problem replacing those "nuts", what's left of them...
I would use 316L for the replacement plates as well as the nuts. Those bolts could also be stainless and I would guess 316 as they show no sign of rust as 304 surely would... and yes, one at a time in the water should present no problem... you might consider putting on a good quantity of sheep fat (anhydrous lanolin) on the threads and new nuts which will make them removable for a very long time