Rusty Keel Bolts - Cost to Fix

[Ken Knull]

We have recently become aware that our Beneteau First 305 (1985) has rusty keel bolts. Since the thought of the keel falling off is not high on my list of fun encounters, I thought I would check online to see if anyone else had experienced this. If you have, I would really like to know what the corrective action was, how it was done and how much it cost! Thanks

 

[scott may]

it all depends

It all depends on how your boat is made and how badly those bolts are rusted. I recently swapped keels on my Catalina 27 due to some severly rusted bolts and the fact that i want a wing keel. This was the high dollar way to go, im not completely finished but my bill (im doing all the work) is hitting at about 4,000 bucks. I will never again worry about that keel tho. If it falls off then God really wants that hunk of fiberglass. You can check into putting new bolts into the keel or even trying the lag bolt method Catalina recomends for their 27's. First remove the rust from your bolts and see the extent of damage, it may not be as bad as you thought. You can see what iv'e done at my web site...www.geocities.comemofish1

 

[James Taylor]

Rusty bolts may not be too bad

Our 1986 First 405 had what I considered to be badly rusted keel bolts. The 405 has a steel keel with the bolts inserted from inside the hull and the hull to keel joint was separating by about a 1/4 inch at the front (a typical problem for this type of design). The yard investigated by pulling out 4 of them and replacing them with high tensile strength steel bolts (the originals were high tensile steel bolts). None of the pulled bolts had any rust whatsoever on the shank or threads of the bolts due to the heavy caulking in the hull to keel joint. So although the bolt heads did not look pretty, the bolts were not in fact too bad. Cost $600. None of the experts I talked to were very concerned about this problem because it rarely leads to an actual failure. Note "rarely", not never. The keel on my boat weighs 8000 pounds and under dynamic loads it could require several times this force to keep it in place. The typical keel is held on with 8 - 10 bolts and each one, if the bolts are sized correctly should be able to take a loading of many times the maximum loading on the entire keel. So there should be quite a safety margin built into the design. It depends though on how much of the head is remaining. You should wire brush all of the rust off and inspect them closely. I would estimate that if more than 25% of the material of the head is rusted away it may be wise to replace it and the large washer under it. To prevent further rusting from the inevitable water that will enter the bilge, you should coat the heads with some form of sealant. Rust priming paint doesn't last. I have used raw lanolin (available in drug stores) recently but it remains sticky and picks up the dirt and in hot weather it tends to run. The next thing I am going to try is to paint them with clear epoxy. On the hull to keel joint we cleaned out the gap as deeply as possible and sanded the rust away in the gap. This is important because if you don't get rid of the rust no sealant will work. We then filled the gap with 5200 sealant and it did not open up the next sailing season. Hope this gives you something to go on.