It was just one short year ago that I tried to mold port light gaskets for the aft cabin port lights and failed. Finally, we delivered our mold to Innovative Technologies in Everett, WA and they cast some gaskets for us. They were just peachy. I encouraged Innovative to only sell full shipsets of eight on further orders, so if you want fewer please find a friend to split with. You’ll want to replace them all, anyway.

Now we’re finally installing the new gaskets.


There are two worst things that can happen: drop and break the glass, or drop and lose a screw (especially out the window). We used Harbor Freight clamps to try and catch the pieces.


The old gaskets were hard as old rubber. Hockey pucks, maybe. I used a stick to pry them over and get access to the screw heads. If you can get to a hardware store, replacing these screws with Phillips Heads would be totally worth it.


Once you get the old seal and glass and trim ring out, break the clamp screws loose and loosen them many turns – five or ten or more. Don’t lose anything.


The frame is held to the coach roof with sex bolts. Yep. That’s a thing.

If you need more, you can get them from McMaster Carr, and if you can get them in Phillips Heads do so. Our frames were inadequately countersunk for the sex bolt heads, so we had to remove the inner piece and deepen the countersink so the heads were flush or below. It makes a mess. Try and hold the outer fastener still so you don’t create a leak around that fastener head.



Clean everything up, stack the glass above the seal ring above the trim ring, and hold it all back up while you reclamp. It’s harder than it looks. We installed the seal rings with the less angled side down, which I think is probably backwards than intended. However, it looks like the seal likes it better this way. There’s less movement as you clamp the window closed.


Reinstall the fasteners but leave them loose. This is a horrible job, but Philllips Head screws would help a lot.


Slide the seal ring out as far as possible and make sure the glass is centered.


Then tighten every fastener.


Close the clamps and adjust the clamp screws. You only need one or two turns after full contact to get a good seal. Too tight and too loose are both bad.


Fill the window with water and check for leaks. If it leaks, tighten and/or loosen the clamp screws slightly. You may need to open and reclose the port if it was too tight, to let the gasket find a new happy place. Remember to empty the window before you open it again.


When you see water in the window and you see water through the window you have reached optimal window.