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Hi all

25 years at sea and I just got my first sail boat.

My 76' CS 27 has a rusty smiley face on the fwd end of the keel where it meets the boat. The previous owner apparently had a soft grounding. I'm getting mixed reviews on where to go next.
It's a cast iron Keel with SS 3/4 bolts installed.
1-Extract a fwd bolt and inspect for corrosion to determine severity of corrosion.
2-Seal the hull again and hit it with the anti fouling and carry on until more time available.
3-Release the keel inspect and replaced all bolts regardless.
4- MMy personal idea to drill an adjacent hole in the bilge big enough to get a boroscope into and inspect and reseal with proper tapped plug.

All suggestions are welcome. Thanks
 

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So it sounds like you have water intrusion to the iron keel and possibly the bolts because of the rust stains leaking out of the “ smile”.

I don’t think the Scope will tell yo what you want to know,

Over years keel bolts loosen. They should be torqued and tightened every few years normally. Many are under masts so if your mast is pulled, that’s a good time.

At the least, and there is no structural damage in the bilge area, the very lest repair would be do that. Fair the keel - hull joint , and then bottom paint. If in one year it reappears then you probably need to drop the keel.

The issue also is that you already know something is rusting in there. The extent can really only be determined by dropping the keel. It may be the bolts....it probably is the iron ballast. Not knowing if it’s encapsulated on your boat , I don’t know.

Was his grounding mud, rock, tree stump? Is there other damage?
 

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I have lead in my cs27, so a bit different, but a couple years ago during haulout, when it was on the slings, I could actually move the keel a bit which would open up the crack slightly. When it was put in the cradle and the weight was bearing on the keel, I tightened each nut. Some didn't move, the two front ones - I got a half turn on each. That was apparently enough to remedy the problem as successive hallouts in the last two years have shown absolutely no signs of wobble and the crack is stable.

In my case, I suspect the lead had compressed a bit where the j bolt embebed itself in the keel - sort of a natural fade over time. With the iron keel, it could be that the corrosion of the iron rather than the compression of the soft lead is the issue. Still, a tightening should help quite a bit, but you may be chasing the problem more each year if it continues to corrode. But who knows? It's a $10,000 boat on the best of days, so I leave it to you whether it's worth dropping the keel. Their are many cs27's around me here, the cast iron ones are all a little rough in the keel, but none have fallen off - it is a CS27 after all and is built like a tank.
 

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it is a CS27 after all and is built like a tank.
:eek:... or a submarine.

I have posted numerous times on my firsthand experience with wet bilges and leaking keel bolts. I am not going to do so again.

I can tell you that NO flexing of the keel is normal, or acceptable, in any fin keel boat.

You may want to read these threads.

https://www.sailnet.com/forums/gear-maintenance/282273-keel-bolt-inspection.html
https://www.sailnet.com/forums/gene...08-keel-bolts-leaking-%96-facing-reality.html
https://www.sailnet.com/forums/gear-maintenance/43505-wet-bilge-more-than-just-nuisance.html
 

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For sure, flexing of a keel would be a breakdown of chemical elements in the iron to an alarming degree. If you can bend a keel, I think I would say it just a matter of hours not days before there is catastrophic failure, but don't think that's the case here. It sounds like it's an attachment failure, and an internal corrosion of the iron surrounding the j-bolts. Unless the bolts are flexing, then yes, not good. But a tightening would reveal whether the bolts are comprimised or just the iron surrounding them.
 

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So, the good news is, you can get the boat on the hard to pull and inspect the threaded studs, in an iron keel, one at a time. You have to come up with a system, but double nutting them is what I did. It's hard to verbally describe, but I needed an elongated socket, made by cutting one horizontally and welding a pipe between the socket end and the wrench attachment. By placing a spacer between the keel nut and the jam nut, the jam nut would be inside the pipe and allowed to get out of phase with the keel nut, effectively jamming them together.

You must do these one at a time and fully replace and torque, before doing the next. It will involve reefing out some sealant and replacing it too. I'd suggest getting a tap to chase the threads and clean them up, but it's probably not mandatory. I did it. My OEM instructions also suggest a light coating of anti-seize on the threads, before reinstalling. While all my bolts were in good order, I replaced them anyway. Be sure to get your OEM instructions and follow them.

We needed a torque multiplier to get them out and, in particular, to get the proper torque on them going back in. That required a minimum of two people. Three were more help, 2 on the multiplier and one steadying the long extension.

The best thing to do is to drop the entire keel and rebed it against the hull. However, if you pull each stud, from the inside, and there is literally no sign of corrosion, that may be unnecessary. With the smile, that may be wishful thinking. However, if there is no sign of water getting to the studs and you want to take your chances, I would clean and seal the keel joint on the outside, after I retorqued all the bolts.
 

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This is a different arrangement than my CS30 so no practical experience with SS Bolts in Iron, but, I would pull and Inspect the bolts with the weight off the hull then act accordingly. If they all look good and will torque properly and the keel can be lowered 1/2" or so, clean and pack the gap with 5200 put the weight back on and re-torque. There are a lot of things that factor into this but that's the broad strokes.
 

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Thanks for that all.
I've decided to drop the keel next year and inspect bolts and do a proper job.
For now I have managed to nip up the nuts to 100 ft-lb, and some actually turned 1/4 turn. I'm leary about increasing any more as I'm not sure about if the threads are dry or not.

Does anyone have a definitive on bolt torque for a CS 27 Iron keel?

Thanks
 

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Thanks for that all.
I've decided to drop the keel next year and inspect bolts and do a proper job.
For now I have managed to nip up the nuts to 100 ft-lb, and some actually turned 1/4 turn. I'm leary about increasing any more as I'm not sure about if the threads are dry or not.

Does anyone have a definitive on bolt torque for a CS 27 Iron keel?

Thanks
That 1/4 turn will help. There is no manual for a cs 27. There is one for a cs30 that may help. If you have a picture of the keel and can give you my to cents worth comparing it to the 10 or so cs27's in my yard which vary in states of repair.
 

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You really need to look it up, but 100 ft lbs seems a bit light to me, for 3/4” studs. SS torques are typically a bit higher than steel too. Making a quarter turn is also a bit concerning, especially if still not to spec. The concern being that they were loose enough to compromise the keel to hull joint and allow water to contact the SS studs, which can corrode them much more quickly underwater than galvanized steel.
 

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Were this my boat, and it's not, I would back one nut at a time completely off, then clean/polish the bolt threads and backing plate, then apply some Tef-Gel to the threads, then torque the nuts to >100 ft/lbs. Removing the nut completely will let you inspect the condition of the bolts, the backing plates and the underlying laminate.

Actually, this IS what I do to my boat every other year.


 

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Were this my boat, and it's not, I would back one nut at a time completely off, then clean/polish the bolt threads and backing plate, then apply some Tef-Gel to the threads, then torque the nuts to >100 ft/lbs. Removing the nut completely will let you inspect the condition of the bolts, the backing plates and the underlying laminate.

Actually, this IS what I do to my boat every other year.


That’s good advice. Must be relatively easy since you do every year.
I may start doing that. Except for 1 of my 10. It resides under the mast step box.
 

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Every OTHER year. One of the seven of mine is almost inaccessible. Persistence pays off.
 

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Were this my boat, and it's not, I would back one nut at a time completely off, then clean/polish the bolt threads and backing plate, then apply some Tef-Gel to the threads, then torque the nuts to >100 ft/lbs. Removing the nut completely will let you inspect the condition of the bolts, the backing plates and the underlying laminate......
A few thoughts.

If the OPs nuts are seized to the stud, they could pull the entire stud. That's not a bad thing, it's even preferable, IMO. But, I'd do it on the hard. I'm just warning that it could be a bit more work than suggested to then get the nut off and clean it up. If it happened, I'd be very inclined to buy new studs.

Have you ever found corrosion on the threads hidden by the nut or under the backing plate that wasn't already visually obvious by the condition of the parts you could readily observe? I've personally found the opposite. Pretty good corrosion on the exposed threads, but beneath the nuts was better. Still replaced it all.

I bed my backing plates in 4200, so water can't get beneath them and less to feel the need to inspect. I just re-did all my keel studs and nuts in 2018. 900 ft lbs!! I literally hurt my back so badly it's only healing about now. :) My OEM instructions were to put anti-seize on the threads that went into the keel, but not beneath the nut.

I had mine retorqued this winter (learned that lesson) and each moved a bit, as brand new studs stretch. Mine are galvanized steel and I'm planning to coat them every couple of years with rust primer. I was going to paint them with cold galvanizing paint (which OEM says is optional), but that would most certainly make it impossible to remove the nuts in the future. The primer is watery.

In the end, the place most likely to corrode is beneath the bilge, especially if the studs are stainless. I think, E, you have molded in studs, but the OP says theirs are iron and I'd take advantage of that and pull them all the way out, if I was going far enough to remove the nuts.
 

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I have not found any pitting or crevice corrosion on my NEW keel bolts. The new keel bolts are 316 stainless, and of a larger diameter (approx 5/8), while the old bolts were 304 stainless, and smaller diameter. Both of these alloys require oxygen to develop their anti-corrosive protective layer.

Because I disassemble and polish, I am allowing oxygen to come into contact with the alloy. One of the old keel bolts snapped when the old bolts were removed, and several looked like apple cores. I believe that the corrosion was able to damage the bolts to the point of failure because the PO never removed the nuts. I pump out the antifreeze and clean out the bilge when I recommission the boat in the spring.

Every fall I add about ½ gallon of undiluted cheap automotive antifreeze to the bilge. I figure that the antifreeze will ward off any freezing, and the anti-corrosion additives can't hurt the steel components.

Here is a graphic from NEMA Enclosures that summarizes the differences between the two stainless steel alloys;
 

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Were this my boat, and it's not, I would back one nut at a time completely off, then clean/polish the bolt threads and backing plate, then apply some Tef-Gel to the threads, then torque the nuts to >100 ft/lbs. Removing the nut completely will let you inspect the condition of the bolts, the backing plates and the underlying laminate.

Actually, this IS what I do to my boat every other year.


That may be the cleanest bilge I have ever seen.
 
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