Leaking ports

[JLBJR]

Both fixed ports on my 28 foot Sabre are leaking and believe it or not Sabre's website offers a section drawing and instructions to help with removal, re-bedding and replacement of the lexan ports. All good news so far, the bad news is this is not as small a job as one would expect and requires things I have no experience with, i.e. "Butyl tape and Silpruf precast white???" A friend recently suggested that a trend in fixed light replacement for old boats like mine is to do away with the aluminum frame completely, make lexan replacements slightly larger then the opening, pre-drill perimeter holes in the new light and screw it directly to the outside of the cabin top using 5200 as a bed and edge sealer. Then make a trim ring of some kind to dress up the inside. Part of me wants to go the "easy" new way, but part of me wants to stay traditional. At the end of the day, what I really want, is to do a good job and to stop the leak. What do you folks think is the best course of action?

Looking forward to your suggestions.

JLBJR

[sailingdog]

IF the aluminum frame is in good shape, I would recommend still using them. Many of the more contemporary boats use much what you're friend suggested—oversized lexan ports held via through-bolts.

If you decide to go with the oversized lexan ports, remember to drill the holes oversized, chamfer/countersink both sides of the holes and to use a good sealant like butyl tape. The holes really need to be oversized so the ports can expand and contract a bit—as they have a different expansion coefficient than does fiberglass. The chamfering of the holes will help prevent stress cracks from forming at the holes.

Really recommend you not use 5200 for the ports. IMHO, that is a really bad idea.

I would also recommend you paint the outer 1" or so of the ports with black paint, preferably on the "inside" to hide the sealant and leave a nice clean appearance to the installation.

[AboardIndigo]

Originally Posted by sailingdog

...I would also recommend you paint the outer 1" or so of the ports with black paint, preferably on the "inside" to hide the sealant and leave a nice clean appearance to the installation.

That's a great tip that I'd never thought of. Thanks SD.

[Freesail99]

The butyl tape, when using it, leave the paper backing on for as long as possible as it will stretch like hell, if you don't.

As far as the fixed ports, on my boat I wasn't able to stop the leaks, even after rebedding. I have teak frames which seem to be impossible to work with. I just bought new opening portlites which are a little bit bigger then my old fixed ports. This weekend I plan on performing surgery on the fiberglass.


Here is a link that may help.

How to install boat windows and port lights

[sailingdog]

Glad to help.

[JLBJR]

Sailingdog, thanks for the input. Is butyl tape some kind of sealant? Is this a marine supply store product? What about Silpruf precast white, ever hear of that?

JLBJR

[JLBJR]

Thanks for the link Freesail99.


JLBJR

[sailingdog]

BTW, IMHO, silicone sealants have NO BUSINESS being on a boat. They are generally prone to leaking and cause adhesion problems for other sealants and paints long after they're gone. DO NOT USE SILICONE FOR THE PORTS.

[sailingdog]

Butyl tape is a sealant that is often used on RVs and automobiles.

[Freesail99]

Black Butyl tape will stain your boat. Use only the white or grey color.