How to fix a leaking centerboard pivot bolt?

[LoveTwoSail]

I am working on a 17' daysailer (Islands 17). We took it for a sail yesterday and water came in around the pivot bolt for the centerboard. I do have access to the bolt.

What is the proper [best] way to seal up a centerboard bolt to eliminate most, if not all, of water leaking into the boat?

 

[Brian S]

Probably neoprene washers between CB trunk, CB pivot washers, and then snug the nuts some.

 

[Crazy Dave Condon]

Ditto with Brian S as that was the old way when done years ago. Once I repaired a boat with bubble gum vs. neophrene. Owner was upset to say the least from the PO that he had just bought the boat from.

 

[rgranger]

I made my own.....

Get a washer and use some masking tape to make a "dam" around the edge of the washer. Then fill it in with Goop (they sell it at Lowes and Walmart). Let the goop dry. It becomes a very hard rubber when dry. (see pictures)

In Pic#1, I had just removed the outer run of masking tape and you can still see the blue tape I used to protect the washer hole.

In Pic #2 you see the before-pic of the washer and if you look to the left you can see one drying that has been all set up.

In Pic #3 you see the final product. The goop drys hard and sticks very well to the metal washer. I then took a sharp knife and cut the edges flush where the goop had crawled up the tape walls. I should have snapped a pic of that but didn't. It turned out perfect and I had a nice flush rubber washer bonded to the washer.

It will take you 10 min. to pour the goop then go back inside, have a beer and watch some TV. Next day it will be hard and ready to use. Then put the rubber side against the keel trunk and tighten it down. Easy peasy and cheap.

 

[Brian S]

Now that I'm thinking about it, I wonder if MaineSail's Bed-it butyl tape would do a good job?

 

[LoveTwoSail]

Thanks for the input.

I used two ss fender washers, drilled to the size of the bolt, with cork/neoprene gaskets, coated with silicon caulk, and tightened almost tight. I gave the silicon a little time to start to set up, then tightened the nut to where I wanted it.

Before I started, I went under the boat and pushed 6 wooden wedges along the sides of the centerboard and the opening. This held the centerboard firmly in place so that when I removed the bolt, the hole in the centerboard plate would stay lined up with the holes in the centerboard trunk. This worked perfectly. After I was done, I removed the wedges and pushed the centerboard up by hand to make sure that it pivoted freely; it was o.k..

The proof will be in the next sail, hopefully no incoming water.

 

[centerline]

Now that I'm thinking about it, I wonder if MaineSail's Bed-it butyl tape would do a good job?

im thinking no... a swing keel bolt will always have some movement and thats the reason for the "rubber" washers. the butyl tape works wonders on a solid mounted object.

a soft, yet resilient rubber that fits snugly around the bolt, with strong washers between the bolt head and the nut will work well.... to make it better, use strong cup washers on the rubber, so when you snug the nut, the rubber will be squeezed by the cup of the washer and bunch it towards the bolt rather than away from it.

a couple of the problems people have in trying to get the keel bolt to seal is, they use too thin of rubber, it does not fit perfectly around the shank of the bolt, or the "fender" washers are either not large enough are too light and they cone OUTWARD when the nut is tightened. this pulls the rubber away from the shank of the bolt and allows the water to seep in... even the slightest bit of washer crush/deformation can let the seal between the bolt and the washer... fail