Need to reseal leaky windows

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K

Kathy

The sealant around the two non-opening windows on my H23 needs to be replaced. Any suggestions on the best product and method?
 
S

Steven de Filippis

i'm going to use marine goop

i have the same problem, i bought some sealant called "marine goop". i have used this before when i installed an electrical outlet in the cockpit, i applied the goop around the seal, it worked extremely well. i want to try to use it around my windows now. i have the same boat, it seems everyone with a 23 has a problem with leaks.
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Contact Hunter Marine.

Kathy: Contact Hunter Marine. They have the correct product for you to use. You need to be careful as some of these sealants can soften your fiberglass.
 
D

Doug T.

Dow 795?

A recent article in Practical Sailor recommended using Dow 795, a structural building sealant. It's not specifically a "boat" product -- it's used for things like mounting windows in skyscrapers. It's inexpensive and comes in a bunch of different colors, if that matters... It's supposed to be compatible with glass & plexiglass. I presume that since they used it on a boat, that it's also compatible with gelcoat. Not sure about Lexan, though. Here's their blurb: Dow Corning® 795 Silicone Building Sealant is a one-part, cold-applied, non-sagging silicone material that cures to a medium modulus silicone rubber upon exposure to atmospheric moisture.
 
Sep 25, 1999
600
Hunter 23.5 Indian Lake
window sealing

ON our h23 I have used life seal or life caulk , you can contact Hunter or west marine, this is a job that needs to be done with regularity , it dries out and then needs to be removed and recaulked, at least that has been my experience, regards Mike Bacome
 
Apr 19, 1999
1,670
Pearson Wanderer Titusville, Florida
Yes Dow 795

It's available from Hunter Marine, they use it for original installation of windows and ports. I bought some from them last week to seal my new windows. The old ones were cracked from the sun and leaking in four places but the sealant around the edges was still watertight after 14 years in the Florida sun. Lifecaulk and 3M 5200 (though good for other specific applications) do not have that kind of staying power for windows. Welcome to the wonderful world of marine sealants. If memory serves me correctly, there should be more info on sealants in the forum archives and the Smaller Boats Forum. Good luck.
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Should not need to be done again if done properly.

Mike: If you use the right product I do not think you would need to do this again too soon. Our Hunter was mfg in 1985 and has NEVER had any of these ports resealed or have they ever leaked. I am real believer in Life Caulk but this is not the best place for this product.
 
K

Kathy

Thanks

for all your suggestions. I did call Hunter and they suggested Dow 736 black, but I can't find it locally. I can get Dow 795 and have some Life Seal. I might use the Life Seal on one window and Dow 795 on the other and see which one holds up better. Kathy
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Get it from Hunter.

Kathy: You can purchase it directly from Hunter. They have a retail sales outlet that sells the stuff. Don't use Life Caulk, like Mike said (you will be doing it again, and again and.....) I guess I'm a little surprised that they recommended 736? I wonder why?
 
R

Ron

USE DOW CORNING 795 AND NO OTHER

I just removed and re-installed all portlights on my H34. Per beckson recommendation I used DC 795. Very easy to work with and have just been through the biggest rain and flood in history of region. Not one drop of water entered whereas before it was buckets.
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
Dow 995

For what it's worth, I used Dow Corning 995 and it has worked really well. It's a tad more expensive than the 795 but it has a longer warranty (the warranty is only for use in building applications) than 795. Hunter probably does not sell this as when it was first introduced one had to be a licensed applicator to buy it but I don't think that is true any longer. It has been somewhere around five years since I reinstalled the coach roof deadlights and ports on my Hunter 35 and nary a drop! Just replaced the oval ports a month ago and there has been several good rain events (Puget Sound) and no leaks. This area is the mother of all leak tests. Comment: A caulked joint has to be properly designed to get optimum reliability. Standardly, the larger the joint the better as sealant is supposed to act more like a rubber band than an adhesive. My boat has very little clearance between the deadlights and the gel coat (horizontally) which was increased prior to applying the sealant and I know this helped. Color: Recommend black for better resistance to UV radiation.
 
D

Doug T.

Permanancy vs. removeability

Hmmm. The product data sheet makes it sound great. But at what point do you end up with something like 5200?? Sure, 5200 will last a looooong time, but when it eventually DOES fail, it's a bitch to deal with. Yes, 995 is a silicone adhesive rather than a polyurethane adhesive, but still... Have you had an opportunity to try to get some fully cured stuff off of anything?
 
C

Chris Gonzales

Framed windows?

I didn't read every reply and your post didn't say if your windows have frames (rather than flush mounted plexiglass), but if so, use butyl tape (putty tape). That's the same stuff they use on RVs and it works great. Place a strip all along the inside frame. Install the window, tightening it down so the putty oozes out around the edge of the frame. Next, using a fairly blunt blade, trim the excess material that has oozed out from the window frame. Done deal. No need to use any caulking of any type at all. After a few days you may wish to check the tightness of the screws in the frame because the putty will continue to flatten out and maybe ooze a little more, too. Usually, after that, no more attention is needed. I installed an opening port in the head as well as a flat traveller using putty tape. This material will keep it's plyability and seal for 5-10 years or more before shrinking and needing to be replaced. At that time it is simply a matter of removing the window, scraping off the old tape and reaplying some new. Chris
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
995 not like 5200

Dow 995 is not like 5200 from an adhesive standpoint. It stays flexible (at least mine has for the past several years) so one should be able to take things apart again. Since our boats were built (mine in '88), Hunter changed the way they installed the deadlights. The xx.5 models used "bump ons" under the Lexan (available at Hunter parts department). These are small neoprene squares with a self adhesive backing that are placed at intervals along the edge of the deadlight where it rests on the coach roof. The deadlights should be sealed on the edges and not rest on sealant. Because the bump-ons raise the Lexan about 1/16-inch up off the recess I pressed some baker rod, a foam rubber material, down in the bottom of the joint and put the sealant in the joint. The backer rod prevented the sealant from creaping under the Lexan. Caution: Be VERY careful when removing the deadlights - they break very easy! Don't force them when removing them or put pressure points such as prying them up with a screwdriver. And, because that plastic is not longer made they can't be replaced. You'd have to go to the smoke color. While some leaks may occur around the edge of the deadlight, the screw holes are where most of the water leaks occur. Recommend drilling out the screw hole in the Lexan so it is slightly larger than the screw so there is some sealant between the screw and the Lexan. Standardly there is very little space between the screw and the screw hole in the Lexan. It may seem odd but when sealant is used a tight clearance is not good because there is not enough sealant for expansion and contraction. Sealant has to act like a rubber band. A good source of information is the Dow company. Besides a help desk you can reach by phone they also have area factory representatives that assist contractors in the construction industry. The 995 is the same stuff that holds the glazing in place for skyscrapers - and no fastners are used! Only sealant is used. Hope this helps.
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
Framed Windows

After posting the last post I read Chris' reply and if you have framed windows please disregard my post. Several Hunters in this time period had Lexan deadlights in the coach roof which was what my response was for. Sorry for the confusion.
 
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