Rusty Keel Bolts

A_Sails_Pace

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As an update to this - I followed the advice and started to clean up the worst looking bolt with a chipping hammer and Dremel with wire brush attachment.. after probably no more than 10 minutes of cleaning up, I hit what felt like pretty solid metal and I am already more reassured!

Matt, can I ask, did you have any hull/keel joint corrosion at the same time? I'm experiencing the same issue as you appeared to have had, only additionally I have a little corrosion around the keel/kull joint. My survey stated that all I needed was to clean up and re-paint the bolts and to sand back the keel/hull corrosion and to flexi mastic it. My worry obviously is that the two are connected? My bilge is usually nice and dry and the bolts are boned as well.

I hope I'm just overthinking and over worrying.

ASP
 

Richard10002

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Matt, can I ask, did you have any hull/keel joint corrosion at the same time? I'm experiencing the same issue as you appeared to have had, only additionally I have a little corrosion around the keel/kull joint. My survey stated that all I needed was to clean up and re-paint the bolts and to sand back the keel/hull corrosion and to flexi mastic it. My worry obviously is that the two are connected? My bilge is usually nice and dry and the bolts are boned as well.

I hope I'm just overthinking and over worrying.

ASP

I had a Moody 44 with similar symptoms. When the keel bolts were removed, the were all fine. I'd had new ones made so they were replaced, but a clean up and paint would have been fine. Similarly, the hull keel joint needed a bit of a scrape and sand. I think I filled it with some kind of Sikaflex. Coat of primocon then painted the whole bottom.

If your surveyor has said that that is all that is needed, that's what I'd do.
 

Tranona

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Matt, can I ask, did you have any hull/keel joint corrosion at the same time? I'm experiencing the same issue as you appeared to have had, only additionally I have a little corrosion around the keel/kull joint. My survey stated that all I needed was to clean up and re-paint the bolts and to sand back the keel/hull corrosion and to flexi mastic it. My worry obviously is that the two are connected? My bilge is usually nice and dry and the bolts are boned as well.

I hope I'm just overthinking and over worrying.

ASP
The corrosion on the keel is highly unlikely to be connected with rusty nuts. The corrosion occurs when the sealant fails and even a small crack will allow seawater to get to the unpainted top face of the keel. If there were any leaks through the keel bolts it would show through streaks of rust coming down the keel in line with the leaking bolt. Follow the surveyor's advice.
 

Elemental

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If your surveyor has said that that is all that is needed, that's what I'd do.

Agreed

If you search this forum for posts about rusty keel bolts, you'll find lots of (understandably) concerned folk with similar issues. I've yet to find a post whereby someone pulled their bolts and found them in a poor state.

On my previous boat (1993 Beneteau) the heads looks like the picture in this thread. The bilge doesn't have a drain hole where the bolts are so any water that falls there can stay a good while. The surveyer looked at them and suggested a wire brush and Galvafroid. I did what he said and the heads cleaned up superbly with very little residual visible damage (I was easily able to get a socket head to seat onto the hex...). Galvafroid is almost as good as galvanising at protecting the metal (so I'm told) and an quick clean every couple of years and repainting appeared to keep them in perfect condition.
 

A_Sails_Pace

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So, tomorrow I’m going to get cracking on cleaning up some of my keel bolts, with much appreciation of the advice in this thread.

I’m just a little unsure of what my bolts are encapsulated with? (picture attached). I plan on sanding, using a Demel where necessary, and using a wire brush to get a good look.

… but as I said, I can’t for the life of me tell what this encapsulation is made of? I’d like to restore it using the same method as it seems it’s been sturdy and safe for a fair few years.

Sorry if it feels like I’m going back over old ground. It’s amazing how divided opinion can be when it comes to keel bolts.

The encapsulation in question…

94ECA75D-3A40-4D03-B366-DED787589EAE.jpeg

Any advice appreciated as always.

ASP
 
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