Keel / Hull join - cause for concern?

[Plevier]

Looks just like my SO32 (lift keel version) as well. I think these Jeanneaus are quite flexible.
Incidentally my keel bolts are plain steel not stainless.

 

[sailorman]

Hi,

She's been inspected (Owen Catchpole) and scraped, and she is fine. It's just a filler issue. I'm doing the update as a thank you to everyone that offered help but also in case someone in future searches on:

Sun Odyssey 35 Keel Hull Joint

Person from the future this is for you - if your cracks look like ours - there's not much to worry about!


Thanks for the advice everyone.

are you about this w/e
we are based there

 

[winsbury]

The keels on our 1980's Pegasus are mounted in a cavity in the hull so its difficult to see if theres been any movement and the moulding certainly doesnt make for very smooth underwater lines, however the keels have never been removed and as far as I know all the filler currently in there is still original. The surveyor has recommended re-filling and fairing with Sikaflex. The overall gap to fair this to the level of the hull is approx 6cm wide by 2 cm deep over 1m long each keel which is 2.4 Litres which at 300ml per tube is 8 tubes the stuff to fill the gap and make it properly fair, this is silly expensive and surely not needed, I assume he just means scrape out the old stuff and refill as best I can though how on earth to do it is a mystery at the moment given the boat is resting on the keels so will be compressing the old sealant.

PS: our keels are held on with mild steel bolts, something I was very wary of and was planning on swapping them out for 316 steel ones instead, however I spoke to the original boat builder and ran this by him and he explained that they deliberately used mild steel as there is much less corrosive activity when used with properly sealed iron keels in the absence of oxygen than would be present with 316. Hence the keel bolts are encased in epoxy internally. 316 apparently needs oxygen to form its protective layer whereas mild steel uses it in the presence of water to create rust. This is why bronze is used for underwater fittings instead of 316 but either can be used above the waterline. I've been restoring the rudder and interestingly there were some 316 penny washers and bolts inside and below the waterline that were completely sealed by epoxy sealant but these are all corroding badly. One for the chemists to ponder but clearly changing keel bolts to 316 might not necessarily be the correct choice.

 

[jwilson]

Hi,

With the boat out of the water I took the opportunity today to have a good poke around underneath her. I noticed that the joint between the keel and the hull has opened slightly - or more likely, that the filler material has cracked and fallen out.

The discolouration of the hull suggest to me that there is some water ingress which is gradually leaking back out - thought the freezing weather seems to have put a stop to it. Am I right about that?

I will be getting it looked at next month - but in the meantime - should I be worrying about this? Am I looking at a major repair or is it something more pedestrian?

She's a S/O 35 if it makes any difference.

Thanks for any input.

I have the same boat, fin keel Jeanneau SO35. The keel is cast iron, coated externally from new with a thin layer of polyester filler-type material to try and cut down rusting.

I doubt very much that there is anything wrong with the keelbolts, though you can get a surveyor to look if you are worried. On a GRP boat taking out a keelbolt is not always a trivial exercise, and certainly not a first course of action.

There is always some movement at a hull/fin keel joint as boats alternate between being in the water sailing (keel hanging down and trying to go side to side as the boat heels), and when ashore resting on the keel - boatyards normally put the full weight of the boat on the keel, and then the other shores/pads are just to stop movement and to stop the hull bending down too much at bow and stern. As others have said, hulls do flex and keels do move slightly. The flexible filler is to cope with this movement.

My own SO35 has a similar, though maybe a slightly less gap in the sealant: she was surveyed last year for charter coding and the surveyor was happy. As this was the same surveyor who dealt with the similar design SO37 that actually lost her keel a couple of years ago I'm sure he would be concerned if there had been a problem. Over the six years I've had her I've re-sealed this joint twice.

By the way, the one that lost her keel did so as a charterer rammed a rock at speed. It did not just drop off!

EDIT - WROTE THIS BEFORE READING ALL THE WAY DOWN THE POSTS - I just saw someone recommending pulling a keelbolt and wanted to say NO - DON'T