Cracks near keel bolts

[babyukalex@yahoo.co.uk]

Dear All, what is your opinion on the following?
This is a Bav 38 2004 long lead keel version.
I have noticed cracks in the bilge near keel bolts  - pls see pictures. These cracks were discovered after marina reported hull flexing while placing boat in the cradle for winter. These are the aft bolts only. The boat was lightly grounded by the previous owner- there is a 2 inch dent in the keel at the very bottom ( off center). Subsequent boat surveys said nothing about these cracks. There are no visible external cracks and the hull-to-keel joint is 100% perfect. There is no water in the bilge, no rust runs on the caulking. All other areas in the bilge have no cracks. Marine engineer recommended replacing washers with SS plates and retightening the keel bolts.

[Happysailor]

Is is difficult to advise on a potential structural issue by a few photos… if you are in real doubt consult a yacht surveyor in the location of your boat to provide you with advise.

About the hull flexing, you will be amazed what happens if a boat is put from hanging in slings to blocks. You will see flexibility in all hulls, first the weight of the keel hanging to the boat en afterwards the weight of the hull and its belongings on the keel. I have had the similar experience with my previous Bavaria as well during the selling survey and the surveyor and also harbour master relaxed me by advising this.

With regard to your cracks, it is a matter if they are only cosmetic in the gelcoat or also penetrating to the hull layers. As said, if in doubt let a specialist help you out…

[JEN-et-ROSS]

The only thing I can add to 'Happysailor' is the presence of the 2" ding at the very bottom end of the keel, and the apparent internal 'cracks' only present at the rear keel bolts may suggest a 'not so light grounding', but one hefty enough to have caused a degree of delamination around the rear of the keel joint......
I would have the area surveyed, partly for peace of mind but also because your insurers could potentially give you grief should a more serious issue arise later and they suspect that an earlier intervention could have saved them a lot of dosh..!!
You never know, they even be willing to pay out for the survey any any subsequent repair that are required now..

[babyukalex@yahoo.co.uk]

Lads, thank you for your comments. The surveyor dismissed the signs of grounding as “old” and “minor” in the pre purchase survey.
Would you still replace those washers with plates or is it irrelevant to hull flexing.

[Happysailor]

With the changing of the washers, very likely the sealant can become detached creating more issues?  Don’t fix what ain’t broken… not leaking, corroding.. would leave it as it is

[babyukalex@yahoo.co.uk]

  thank you for reassurance- that is what I was going to do.

[Yngmar]

What Happysailor said. If you really want to assess the damage, you can carefully grind away the brown flowcoat where the cracks are and expose the laminate. You will then see if there is delamination (white) or solid fibreglass.

Generally, the flowcoat is very brittle while fibreglass is slightly elastic and can absorb some shocks undamaged that cause the flowcoat on top to crack.

The damage doesn't look very large and I agree with the surveyor.

I would also leave the washers and bolts alone, they've never been known to be an issue and no reason to mess with them.

Some hull deflection when shifting weight from a 3 ton keel hanging from the hull to it sitting on the ground with 7 tons of boat pushing down on it is normal. If there's any keel movement (sideways) while in the slings, that would be cause for concern.

[IslandAlchemy]

Looks to me like bits of flowcoat cracking away. This happens because it's difficult to get rid of all of the release agent before painting with flowcoat, so it can come free and once a bit of moisture gets under it, it starts to come off as yours has.

This also happens near the tops of the stringers where the frame has been glassed onto the hull, and then painted with flowcoat.

I would ignore it.  There's no sign of any movement.

[babyukalex@yahoo.co.uk]

Thank you,
For future reference, what brand flow coat does Bavaria use? - my OCD will force me to restore it to the “brand new” condition.

[babyukalex@yahoo.co.uk]

So I will likely grind some of the flow coat ( as per Yngmar’s suggestion)- asses and then repaint.

[Yngmar]

Brands are irrelevant, any polyester flowcoat will do. You may find the RAL code somewhere here on the forum, if not you'll have to do some colour matching.