sealant, Swing Keel Pivot bolt

snick

.
Mar 21, 2022
7
Paceship P14 west hill
Hi I am looking for suggestions on using a sealant for sealing a swing keel centerboard pivot bolt.

I just completed work on the swing keel on an old Paceship, I now am going to apply 4200 sealant to the swing keel pivot bolt. There is a rubber washer, stainless washer on both ends of the bolt which seal against the fiberglass of the boat.
I plan to apply the sealant between pivot bolt head and stainless washer as well as the other end of the pivot bolt nut and washer. Is that enough sealant or should I also apply sealant on both sides of the rubber washer as well as the end threads of the bolt?
Thanks
 
Jan 11, 2014
12,833
Sabre 362 113 Fair Haven, NY
Is the bolt beneath the water line? If it is above the water line then the rubber washers should provide enough protection from water splashing up in the centerboard trunk.
 

snick

.
Mar 21, 2022
7
Paceship P14 west hill
Is the bolt beneath the water line? If it is above the water line then the rubber washers should provide enough protection from water splashing up in the centerboard trunk.
I wish it was but It is below the waterline. The original sealant I removed was white and still somewhat flexible after over 50 years. Ive read that some put the sealant just under the bolt head and bolt nut and other coat every thing.
 
Jan 11, 2014
12,833
Sabre 362 113 Fair Haven, NY
I suspect the original designers expected the rubber washer to be the seal. At this point I'm not sure it is necessary.

I'd be inclined to bevel the bolt hole on both sides, use a countersink bit. This will form a little valley to bed the washer and bolt. Put a good dollop of caulking in the bevel slide the bolt and washer through. Another good dollop of caulk on the nut side, then the washer, and nut. I would use a nylon nut, more secure and less likely to corrode to the bolt.

Tighten the nut, not the bolt. Once the bolt is in place try not to rotate it. If it spins a lot it could force too much caulk away from the bolt and hole, not what you want. There should be good squeeze out when the bolt is tightened. Let it fully cure before launching.