Keel Bolt Maintenance

rukidn

.
Apr 23, 2012
158
Catalina 310 258 Sandusky, OH
My keel was weeping when I pulled the boat last fall and I've been immersed in repair and refair. I'll start another thread on that soon. During the repairs I wanted to reseal and re-torque the nine keel bolts, which has not been done in the 4 years we've owned the boat. What I found was a mess left by the PO or his boat yard.

First, Warren at Catalina was quite helpful with torque specs and a drawing of how to seal the keel bolts. Minimum torque is 90 lb-ft and target is 100 lb-ft. I started one bolt at a time and found they loosened at 50-90 lb-ft. The sealing procedure is to place an o-ring under the washer, along with a sealant, and torque. We cleaned the sealing area, followed the instructions (we used Lifecaulk, NOT 5200!), and all was well for a few bolts. By the way, the 1"-8 nuts take a 1 1/2" socket.

We found that the washer for the forward-most bolt was epoxied down and I had to use a pencil torch to break it loose and pick the loosened epoxy out of the threads. We tediously cleaned up the area and sealed per procedure. The port center bolt was also epoxied, but the real problem was that the starboard center bolt would not back off at more than 300 lb-ft. We fought for 1/4 turn and then frozen solid. After 1/4 turn, the lock washer was loose, so this bolt was never tightened and absolutely carried no load. I'm a mechanical engineer and know a bit about stainless bolted joints, so I immediately set about cutting the nut off. A vertical slit with a dremel and driving in a chisel opened the nut enough to remove. Easier than I thought it would be considering the size. The male threads were trashed, as the nut had literally welded to the bolt.

Never keep turning a galled stainless nut or bolt. Things will only go from bad to worse. Stainless is protected by an oxide layer that actually achieves the corrosion resistance. If this layer is removed, the raw alloy is susceptable to galling. During torquing, even a small bit of contamination will remove the oxide, and the raw surfaces will literally friction weld to each other, roll up a larger ball, weld a larger area, on and on until frozen. Think of a snowball.

The threads were bad enough at the top that a new nut would barely start and were worse near the bottom. Never force it. I bought a 1"-8 rethreading die which is driven by a 1 7/8 socket. Fortunately there was just enough clearance for the socket. I first cleaned up the port side bolt which had epoxy in the threads, then re-threaded the frozen bolt. It took some work, but cleaned up nicely and the new nut spun on easily. Finished sealing and all is well.

I don't know what hack did the prior work, but I certainly hope my boat was an exception. I highly recommend checking keel bolt torque based on what I found, and resealing if on the hard and dried out. I wouldn't recommend resealing while in the water. Next time I do this I will clean up every bolt with the re-threading die ($20), which will clean out old sealant and remove any burrs that may cause galling. Using an anti-sieze compound on bolts this size is also appropriate.
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Likes: SimiSAilor
Mar 11, 2015
357
Hunter 33.5 Tacoma, WA
Isn't a weeping keel a sign of bigger issues? My keel doesn't have any sort of joint cracks so I'm not about the "re-torque" them just for the heck of it.

If your keel is weeping it's best to drop it and fix the obvious delamination that MUST be occurring underneath.
 

rukidn

.
Apr 23, 2012
158
Catalina 310 258 Sandusky, OH
I'll start a separate thread on the external keel as soon as I finish fairing. My point in this thread is the suggestion to periodically check keel bolt torque. The complications I found notwithstanding. Such bolted joints will embed and loose tension over time and load cycles. In brief, I consulted with several professionals and Catalina prior to repairing the joint in place. Our keel stub joints are laminated with 6" fiberglass mat and tape. I found that my fairing had de-laminated from the fiberglass, but the glass was tight to the joint. A dull knife peeled the entire perimeter in minutes. From the looks of things, the laminate fiberglass had a gloss and was not roughed up in any way. Fine if the fairing was applied prior to the epoxy curing, but if the epoxy was fully cured prior to fairing and not roughed up, it could lead to what I found.
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
I'm with mz, something is not adding up or maybe it's the way I am reading it.

If you had water coming in from the keel bolts there has to be more of an issue than just keel bolt tension. And if it was just the fairing compound that was delaminating, how was the water getting in? I would defiantly like to know more about this problem and repair.

Please post more details when you can.

Thanks.

Jesse
 
Aug 24, 2009
444
Catalina 310 Sturgeon Bay, WI
Not fully off subject here I hope, but my yard started a Boat Buck Plus project on my keel Friday. That well known Catalina Smile - well it got to the point that over the winter water migrated into the crack, and flowed down under the fiberglass (between keel and stub) and was frozen over the winter. Now I have two (2) large cracks in the fairing one each side of the keel, where the material pulled away from the lead. Fairing and fiberglass don't adhere well to lead, so there is a lot of grinding, and then he will use a flexible material between keel and stub before wrapping another glass band around and fix it all. My point is, looking at how this is put together, not sure how water would get between keel and stub, find the keel-bolt, migrate up the bolt to weep inside the bilge. I agree with the above, if this is happening, you have major problems as water trapped in the fiberglass stub and with the stainless steel bolt could be causing rot, and oxidation of the bolt themselves. Are you sure you were not just seeing condensation from cold water contacting warm air in the bilge, or slight amount of water intrusion from other places? What you undertook looks like a lot of work, and bad thing is if water is coming up from below, all you have done is trapped it below the washer to continue to do damage, (they always say never fix a leak from the inside, that water has to go someplace.) Anyway thought I would throw that out there, what I though was a little crack 2 hour job is now setting my spring launch back 2-3 weeks.

Russ
s/v Long Story
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
Not fully off subject here I hope, but my yard started a Boat Buck Plus project on my keel Friday. That well known Catalina Smile - well it got to the point that over the winter water migrated into the crack, and flowed down under the fiberglass (between keel and stub) and was frozen over the winter. Now I have two (2) large cracks in the fairing one each side of the keel, where the material pulled away from the lead. Fairing and fiberglass don't adhere well to lead, so there is a lot of grinding, and then he will use a flexible material between keel and stub before wrapping another glass band around and fix it all. My point is, looking at how this is put together, not sure how water would get between keel and stub, find the keel-bolt, migrate up the bolt to weep inside the bilge. I agree with the above, if this is happening, you have major problems as water trapped in the fiberglass stub and with the stainless steel bolt could be causing rot, and oxidation of the bolt themselves. Are you sure you were not just seeing condensation from cold water contacting warm air in the bilge, or slight amount of water intrusion from other places? What you undertook looks like a lot of work, and bad thing is if water is coming up from below, all you have done is trapped it below the washer to continue to do damage, (they always say never fix a leak from the inside, that water has to go someplace.) Anyway thought I would throw that out there, what I though was a little crack 2 hour job is now setting my spring launch back 2-3 weeks.

Russ
s/v Long Story
This is interesting because the Catalina Smile in on boats prior to 1989. It comes from wood being used in the keel stub. The wood rots and the keel sags and you get the smile.

Have you had any significant groundings that could have caused damage to the keel? Just not sure about the cause of the damage you are now fixing.
 

rukidn

.
Apr 23, 2012
158
Catalina 310 258 Sandusky, OH
Sorry Russ, that yours progressed so far. I did not have water coming up the keel bolts. I had a dry bilge except when running the air conditioner. When the boat came out the fairing was quite cracked up. Sorry if I confused with the term weeping. Water ran out of the cracks in the fairing. I immediately attacked the loose fairing and it came off quite easily. 3" x 6" slabs. My fiberglass band was tight to the lead and stub however. I'm guessing the -25F deep freeze/thaws of the 2014/15 winter did the work to delaminate the fairing, and I should have checked it last Spring. If I'd had water behind the fiberglass, I surely would have ended up same as you. I'll try to get pics together after final sanding, barrier coat, bottom paint next weekend. Traveling at the moment.
 
Aug 24, 2009
444
Catalina 310 Sturgeon Bay, WI
This is interesting because the Catalina Smile in on boats prior to 1989. It comes from wood being used in the keel stub. The wood rots and the keel sags and you get the smile.

Have you had any significant groundings that could have caused damage to the keel? Just not sure about the cause of the damage you are now fixing.
I have not, but does not me a PO didn't have one. My dealer looked at it and said it was a matter of the sealant they fared it together with getting old, and cracking out... there is a band of glass mat wrapped around and then this filler used. I guess they now use something more flexible.