Butyl tape or 4200 for windlass thru holes?

[Cheapie408]

I use butyl tape to intall the handrail and love the ease of use. I read that above the waterline many people swears by this. Thinking of using it to seal the windlass thru bolts as well, would this be a suitable application for it?

BTW I also applied a couple coats of epoxy on the inside of the expose wood as well for safe measures.

 

[knotflying]

I would use the butyl tape. Perhaps countersink the holes just a little so it gets forced down into the hole better and it will make a better seal. I would just use a little around each bolt. My rule of thumb has always use butyl on deck surfaces.

 

[Cheapie408]

i went ahead and did that yesterday.