Replacement Seal of Goiot Deck Hatch

[Pieter]

Esteemed forum members, first of all from Brazil a great 2011 for all...

Now, between the rain showers, i thought it to be a good idea to replace a rubber seal in one of the Goiot deck hatches... as i noticed that a little rain water was seaping through.... Took the old seal out, indeed it was worn out, cleaned the rim of old rubber and glue traces.... cleaned also the actual acrylic.. and measured and put the new (original from Goiot seal back using only a little superglue to keep it in place.... Was indeed a 5 min job. "Tested" the seal by using my deck shower for a couple of minutes, and boy was i happy to see that the cabine remained dry....
So, this morning (overnight we had torrential rains again) i checked the hatch.... big dissapointement: water all of the place...How is this possible? How difficult can it be: replacing a seal... and even after using for a couple of minutes the deck shower and all seemed ok... (i understand that there is a difference in the deck shower and a couple of hours downpour but even so...). Anyway, anybody a hint, suggestion, idea of what i should do different?

Thanks a lot and best rgds
Pieter Kommerij
SV Onda Boa
www.luminacharters.com.br

[KDH]

Hi Pieter. Not sure if you mean you removed the acrylic lens and tried to reuse the rubber seal around it? Or if your hatch has a rubber compressible seal where you pull the hatch closed? We have Goiot hatches on our monohull and recently had a leak around the base of the hatch when rain was driven sideways by the wind. The water would get into to the plastic trim on the underside of the deck and then run along the edge and drip on the bunk. I ended up removing the hatch from the deck and it came up quite easily. Rebedded underneath with butyl rubber which took quite some time. Halfway through I wished I had used a caulk instead. If it's the acrylic lens you are talking about I suggest removing all the old seal and resealing with a new sealant. My Goiot lens are acrylic and I assume yours are too. To quote GordMay: "Most hatches have anodized aluminum frames, with Acrylic (Plexiglass™) or Polycarbonate (Lexan™) glazing (not glass), for which a mediun or hi-modulus neutral curing silicone sealant, such as Dow Corning 795, (NOT acetoxy* cure) is usually recommended.

You should probably seek specific recommendations (performance & compatibility) from your glazing supplier.

* If acetal cure (oxime) type silicone base sealant is used, the emitted gas causes corrosion & cracking (in plastics).

If your replacement glazing is actually glass, I'd recomment either a polysufide or apolyurethane adhesive sealant." The original thread is at: http://www.cruisersforum.com/forums/...lass-9410.html

Good luck with the repair and Happy New Year to you as well! Cheers, Kim

[donradcliffe]

While I have some new Goiot rubber seal material, I have found that most leaks are either between the aluminum frame and the fiberglass, or between the plexiglass lens and the aluminum frame. Silicone is typically used for both applications, and can break down over time due to the differential expansion between the aluminum and the other materials in the sun.

I also know that its amazing how an area that doesn't leak under the pressure of a hose jet can leak in the rain...to check if its the lens-frame joint that is leaking, I tape up that joint temporarily with the blue masking tape from 3M and see if that cures the leak.

[Pieter]

Thank you Kim, actualy i am talking abt the compressible seal... the actualy "window" seems to be in tact and ok. So, in my opinion, i can not use the silicon option, as i open and close the hatch for ventilation purposes... and so that is why there is this rubber seal inbedded in the alu frame... when closing the hatch some pressure is applied when closing and so i thought it should keep the water out....
Thanks for your valuable comments, and will check what i can do...

[Pieter]

Ok Don, thanks.... Just to make sure, i will put a sealant between the fibre glass and the alu frame, although it seems that that is not where the water enters... Thanks for your comments.
Best rgds
Pieter