Iron Keel Rust

[J. P. Plata]

I recently became a sailboat owner. The keel is made of iron pellets, about 2 inches in diameter, inbeded in what appears to be cement. Salt water reached the bilge and now the top layer of the keel is cracked and the exposed pellets are rusting. I fear salt water might have gone deeper and would like to know if there is a way to stop the oxidizing process. I thought phosphoric acid but it would just eat the whole metal away...Any suggestions?

 

[Peter J. Brennan]

Ooh! Awful!

What boat is that? I never heard of a composite iron pellet-cement keel. What's on the outside below the hull? Is it encapsulated in fiberglass? The problem with rust is that it takes up more space than the original metal and does so as an irresistable force which is why you are seeing cracks. It may well be that as the top layers corrode and crack, water is admitted to lower layers where the same process will continue. You just might have to go in there with a jack hammer and dig until you reach sound material thenuse the usual iron protective means to prevent further corrosion. Having once owned a boat with an iron keel, albeit solid iron, my advice to anyone is -- DON'T! But your situation is even worse. Sorry can't be more help.

 

[Steve Dion]

What did the survey say?

Did you have a survey? What did the survey say? If you did not have a survey I would consult a yard and ask them about it.I would think that cleaning out the area and then pouring epoxy to seal the cracks would be your best bet. You could also drill some holes at different areas of the keel and see if any water seeps out. These can also be sealed with epoxy when you are done.