keel bolt leaking.

[aquapore]

Hi Guys

My BAV 41 (2003) has developed a leak around one of the keel bolts. I confirmed this by sealing a short length of pipe around the suspect to isolate and capture any water that came from that bolt.

The leak occurs only when the the keel is being stressed. No leak during mooring.

The volume of the leak might be about 100ml per 6 hours.

Would appreciate advise of remedy, the seriousness of the problem and the urgency of the remedy.

Regards


Aquapore

[Symphony]

The only way water can leak out of the top is if the seal between the keel and the hull is broken. Unusual to be just one bolt. First test it is definitely seawater. If so then the boat needs lifting and the joint between the hull and keel inspected. It should be obvious if the seal has failed because there will be rust stains, and probably water running out.

Only long term solution is dropping the keel and then resealing. Depending on how long water has been getting in you might have to replace at least the one bolt because there is probbly crevice corrosion where the bolt meets the keel.

[aquapore]

Thanks Old Salt.

The leaked  water is definitely sea water.

I will check other bolts but the bilge was generally free from salt water although I was tracking down deck fitting leaks when I conducted this investigation.

When the boat was lifted last year there was no evidence of hull/keel seal failure.

I will keel the forum informed.

Regards

Aquapore

[Sen Mora]

I can suggest tightening all keel bolts once the boat is on hard. In the mean time just watching it that it does not get much worse.

[Harry Brown]

I thought I had this problem early last year. Fortunately, it was not a leaking stud, it was a rain water leak that tasted salty. I was adamant at the time that it was a stud leaking, it turned out thankfully, I was wrong.
The way the water collects around the bolt/stud is very deceiving. I took a video of the water gathering and slowed it down to actually find it was coming from a bilge drain hole adjacent to it.

Here are the threads I started here and over on YBW when I thought I had the problem. I hope they help.

http://www.bavariayacht.info/forum/index.php/topic,1216.0.html

http://www.ybw.com/forums/showthread.php?448651-Keel-Bolt-Stud-Leaking&highlight=

I hope you find out like I did that it is not a stud/bolt after all.

Good luck.

[aquapore]

I read the links from Harry. It talks about "withdrawing" the bolts.

Are the retaining buts arrached to bolts or are they studs cast into the keel.

Also my boat suffered a grounding on rock which I refloated after several attempts with the engine during which I managed to "pivot" the boat causing the stern to rise up pressing the bow into the water and off the rock. It may be that  event has given rise to the present problem.

Anyway it appears to be a serious and expensive problem.

Regards

Aquapore

[Symphony]

They are studs. You don't say which bolt it is, but if it is towards the end, particularly the aft end, the grounding may be significant as the keel tends to depress the hull immediately aft, or pull the keel down forward. This is a common cause of breaking the seal between the keel and hull.

If it were my boat I would lift it immediately. If the grounding was an accident you may have luck with a claim on your insurance.

[aquapore]

Thanks for your input.

Boat to be lifted next week - insurance claim.

Will post result if interesting.

Regards

Aquapore

[Harry Brown]

Definitely would be interested in your findings.
Good luck.

[aquapore]

Hi Guys

Insurance claim accepted. Boat lifted yesterday.
Seal between the hull and keel broken as evidenced by air bubbles coming out of joint when keel wobbled by hand Hull and keel were wet.

The rudder leading leading edge also cracked from impact.

Surveyor reports only one keel bolt leaking.

As part of the operation the mast also has to be removed because of stability problems when keel removed.

Insurance company and its surveyor have taken the damage very seriously to my pleasant surprise.

Will have standing rig replaced while mast is out.

I will send pictures when the keel is remove.

Thanks for your interest.

Regards


Aquapore.

[Craig]

aquapore,

Have a read of the annexures of the MAIB "Cheeki Rafiti" report, in particular the repair methods for the Hull- Keel join.

I would recommend that additional reinforcing be done in the area as the repair method may not be able to identify or fix the problem properly.

Craig
"Shirley Valentine"
Gold Coast
Australia

[Symphony]

While that is a useful report in many ways, it highlights the fact that there is no agreement on the "best" way to repair such damage, if only because the damage is not always the same in each case. Add to that the grid construction on the First is different from that on a Bavaria. Much more important is that the surveyor and repairer have experience with Bavarias.

[aquapore]

Thanks for the advice.

The report from the ship wright is there is nothing too see at the joint. He has taken photos which I have yet to see.
Read the report into "Cheeki Rafiti" which is a Beneteau First 40 which has a structural floor bonded to the hull to provide the reinforcing beams. The Bavaria is different having its structural beams moulded integral with the hull which I believe is more secure.

It is noteworthy that the crew of "Cheeki Rafiti" in communication with their support base were unable to find the source of the water ingress for at least two days before the catastrophic failure which cost them their lives. They did not have time to launch their life raft.

I might well be that the root cause might be that the bond of the structural floor might gave been compromised leading to a series of further damage hull at the location of the bolt supports.  The report does not speculate as to the cause but the photographs of the upturned hull is not what one would expect of the keel bolts simple failed.

Regards

Aquapore

[Scotty]

2 years ago my keel glanced an underwater object off the coast of Italy. Small amount of water ingressed around keel bolts. Had the boat lifted immediately and found keel/hull seal cracked. Subsequently keel was dropped, not a pleasant procedure to witness,(mast remained standing). The hull adjoining keel was rebonded, epoxied and sealant applied before attaching keel. Keel bolts were in good order. Good job done and paid by insurance too. Over 2000 miles sailed since no subsequent problems experienced.