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Keel Bolts and General Topics on Keel - 43/26 keel bolts
10 June 2021 - 11:46
#1
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Dieter
Join Date: 26 May 2021
Posts: 3

43/26 keel bolts

Dear Lars, dear all,

after a few months on the hard doing an osmosis treatment we finally launched and soon detected water in the bilge, and subsequently a crack in the aft keel joint. Above the area, where the trim tap used to be. The water seemed to infiltrate through one (or more?) of the keel bolts in the sump. A few days later we put the boat back on the hard.

Do you know, if my boat (43/26) belongs to the early models, when the bolts went all the way through with nuts on the lower end, or if the keel bolts were cast in? What could be the reason for the leak, the crack, bad/old sealant around the bolts (only on top or further down, if that option applies), a combination of all? There are no other cracks to be seen and the rest of the bilge is dry.

Thanks for your help, all the best
11 June 2021 - 06:22
#2
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the professor
Join Date: 02 January 2008
Posts: 1547

Dear Dieter

Unfortunately I do not know how your keel bolts are anchored, suggest you  uncover the keel lead surface over a suitable area, then you will see if there are pockets for the bolt lower ends or not.
As it seems that just one or two keel bolts are leaking, you could try the following on them from the inside:
Take off the nuts and washers, and with a long hole drill bit a little bigger than the bolt, try to clean out the slot around the bolt right down to the lead surface. If the bolts sit in holes in the lead keel, continue say 5 mm down from the top of the lead.
Check if there is moisture, and dry it out by flushing with acetone. Check if there is corrosion on the bolts, fiber optics are probably needed in the narrow slot
Then fill the slot carefully with a suitable thin mastic (non thixotropic) up to the top of the washer, which should be of the maximum size that fits, and thick enough. Finally tension the nut.
Questions?
Kind regards
Lars
11 June 2021 - 14:26
#3
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Dieter
Join Date: 26 May 2021
Posts: 3

Dear Lars, 

Thank you very much. Will do as you suggest. Because of medical reasons I am back in Europe right now (the boat is in Grenada), so it will be a little while. 

Can you recommend a brand name for the mastic?

Will keep you updated once it's done. 

Thanks again and all the best 

Dieter 
11 June 2021 - 15:00
#4
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the professor
Join Date: 02 January 2008
Posts: 1547

Dieter

3M 5200 should be readily available in the Caribbean
Lars
13 June 2021 - 13:12
#5
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Dieter
Join Date: 26 May 2021
Posts: 3

Dieter

3M 5200 should be readily available in the Caribbean
Lars

Thanks Lars! 
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