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  Topic Review (Newest First)
05-20-2010 09:31 AM
henryyork OK-Here is how I have learned to do it, and thanks to all of you who have replied.

Step 1--if you don't already own one, go to an auto glass shop that will sell you a tool called a "bone".

Step 2--grate a bar of soap into shavings and make a slurry of soapy water.

Step 3--cut the gasket to size.

Step 4--use a paint brush to lubricate the interior slot of the gasket with some slurry.

Step 5--insert the pane in the interior slot of the gasket

Step 6--cut a length of 1/4 inch line, or whatever dimension fits snugly in the exterior slot of the gasket, long enough so that you have ends hanging out long enough to get a firm grip on-- you can use constrictor knots around the middles of a pair of 3"-4" dowels to make the pulling extra easy.

Step 7--slurry the exterior slot, and have one person put pressure on the top of the unit from the outside, making sure that the solid side of the gasket is outside, the locking part on the interior, and that the gasket is unlocked. The person on the inside (the strongest is best) works the gasket onto the hull edge, starts slowly pulling out the rope while the unit is being forced down, helping to spread the gasket onto the hull edge with the thin end of the bone. Work around the port hole in both directions.

Step 8--when the gasket is on all around, slurry the locking surface and, using the wedge end of the bone, tuck it into its slot in a series of jabs--it won't work if you try to just run it around.

Step 9--wash and dry the portlight. That's it. I have done one (5 to go) using this method so I know that it works, but it does take strong fingers.

Thanks again to those who have shared advice.
04-25-2010 02:31 PM
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.
04-25-2010 10:40 AM
henryyork Thank you guys--what a great help you are!
04-24-2010 09:08 PM
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.
04-24-2010 03:47 PM
mitiempo No sealant is used with that kind of gasket. I don't think the ends use sealant either.
04-24-2010 02:12 PM
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.
04-23-2010 11:29 AM
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 View Post
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.
04-23-2010 10:48 AM
Portlight/Gasket Replacement

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.
04-22-2010 10:43 PM
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.
04-22-2010 10:26 PM
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.
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