Leak from safety line stanchion on our Hunter 376

[ghsmindy]

Finally isolated the source of a leak into the alcove at the head of our bed in primary cabin. It is coming through the bolts holding the starboard safety line stanchion in place, (where one exits the deck onto the dock.) By removing a panel in another location we found that these bolts have nuts under the deck, but have found no access to them outside of cutting through the head liner, not hull, of our cabin. Anyone else experienced this and have a better solution?

 

[ghsmindy]

Actually, without cutting through the head liner, not the hull.

 

[Tally Ho]

Actually, without cutting through the head liner, not the hull.

Hunter may have put a piece of aluminum in the glass in that area, so you don’t need a nut on the bottom.

I would try to remove the bolts from the top, and see if the back out. If so, I think you have confirmed the aluminum plate is there.

After you remove them, clean the area well, and use Bed-it butyl tape around the bolts to seal them And reinstall.

Greg

 

[marcham]

On my 380, there's no need to access a nut from the bottom.... all the stanchions have embedded metal plates to secure the fasteners.

If you use Sika 291, don't completely tighten the fasteners ... leave about 1-2 turns to finish the fasteners after the sika has just started to cured (but still sticky). That gives a lot of elasticity to the joint in case of future movements and prevents water ingress a bit better than butyl as it is well adhered to the gelcoat and the metal (in my experience).

It's a good idea to rebed all the deck hardware after 20 years...

 

[Project_Mayhem]

Use TefGel when re-installing so you don't have issues next time the bolt needs to come out

 

[dlochner]

If you use Sika 291, don't completely tighten the fasteners ... leave about 1-2 turns to finish the fasteners after the sika has cured. That gives a lot of elasticity to the joint in case of future movements and prevents water ingress a bit better than butyl as it is well adhered to the gelcoat and the metal (in my experience).

This is an oft recommended practice with Don Casey often cited as the source. In theory it sounds right, commonsense right? No.

When a sealant, like Sika Flex, Lifecault, 4200, etc is used the sealant will adhere to the fitting, the deck, and to the threads on the fastener. This adhesion is what makes it water tight. When a fastener is tightened after the sealant has cured, the adhesion to the fastener will break providing a pathway for water to seep through the hole. The increased pressure between the fitting and the deck will also stress the adhesion between the sealant and the deck and/or fitting.

Just tighten the fitting so that it is secure and there is good squeeze out around the fitting and let it be.

 

[marcham]

Yeah, the trick is not to let it dry completely.... just give it about 30-60 minutes to get a little thicker. Once it's dry, it's too late! Or as you say, just tighten it and walk away...

 

[Project_Mayhem]

As @mainesail has pointed out, it's hard to get consistent results with this technique. Bed-IT would be my preferred sealant for this application