Portlight/Gasket Replacement

[henryyork]

I have new acrylic portlights and gasket material from Hammerhead Nautical Systems in Canada to replace the original portlight in my 1965 Westerly Nomad 22. The gaskets fit the thickness of the GRP topsides, and the portlights, but repeated requests for written instructions on the steps, materials, and tool(s) for installation to HHNS have elicited no response. There are no frames--the outside groove in the gasket seals the edge of the port hole and the portlight fits in the inside one, but I have no clue about how to proceed to install them. Anyone done anything like this?

[sailingdog]

Do you have photos of the opening, gaskets and portlights?

Have you tried installing the portlight into the gasket and then putting the whole unit into hot water and then trying to fit it into the opening? Heating the gasket should make it more pliable and easier to fit into the opening.

[mitiempo]

dog
I used to own a Westerly. Their ports use an "H" shaped gasket with one slot mating with the cabin side and the other mating with the glazing. I never had leaks so never had to replace the gaskets.

[henryyork]

I will take some pics--good idea.

I will also try the hot water trick--thanks!

The old ones did not leak, but the lights themselves were getting badly crazed, and the gaskets were, though not leaking, getting very dry and cracked on their exterior surfaces.

[sailingdog]

I figured as much from the OP's description. I've replaced ports like this, but not on a boat.

Originally Posted by mitiempo

dog
I used to own a Westerly. Their ports use an "H" shaped gasket with one slot mating with the cabin side and the other mating with the glazing. I never had leaks so never had to replace the gaskets.

[henryyork]

One more question, assuming that the hot water trick works

Should there be a sealant or an adhesive, or combo of the two in a single product for the joint where the two ends of the gasket meet, assuming it's a solid joint, or should there be a slight gap there to be sealed? And is the H gasket likely to need sealant on both sides (hull and portlight)? When I removed one of each size to send to Hammerhead Nautical Systems for patterns for their replacement there was no evidence of any sealant in the original installation.

[mitiempo]

No sealant is used with that kind of gasket. I don't think the ends use sealant either.

[sailingdog]

No sealant as far as I can recall, and I'd add that the seam should be at the bottom of the port IIRC.

[henryyork]

Thank you guys--what a great help you are!

[IslanderGuy]

I have these windows on my 1964 Islander, and recently had to replace the sealant between the ends of the gasket, as there is quite a large gap. (1/8 inch or so) and it was leaking. There was sealant in the gap before, but it was no good any more.

This could be due to the gaskets being very old, and you may not need sealant for new ones as others have mentioned, but I use it on the old ones.

BTW, I have not seen any sealant on the rest of the gasket, just at the joint of the two ends.