Butyl Caulk and Rubber Seal for portlights

jhenson · Post by **jhenson** » Sat Feb 26, 2005 9:58 pm

I have read the post on this forum that recommend butyl caulk for sealing portlight frames. Can anyone suggest a source for a tube of this? I live in a small town, and thus far haven't found it.

Also, I have the bronze (early) Triton portlights. There is a 1/8" contiguous rubber seal that fits in a groove in the frame to keep keep the weather out when closed. Mine have absolutely no life left in them. You can see daylight all the way around the seal. Any ideas on replacement materials? I have thought of cutting household adheasive-backed weather stripping into the required width of the groove.

Joe

Post by **Tim** » Sun Feb 27, 2005 10:31 am

I can find butyl caulk at my local Ace, in amongst the other types of caulking.

I'm not that familiar with the design of the old Triton ports like yours. Mine take a 1/4" square section of portlight rubber, which you can find at Defender or places like McMaster-Carr. McMaster has everything...sometimes, the problem is just knowing what to call it so you can find it!

I doubt household weather stripping would hold up too well; it tends to be pretty flimsy.

Dan · Post by **Dan** » Sun Feb 27, 2005 10:58 am

I did one badly leaking window in the past (see archives "windows tra la," as I recall) and I used auto butyl tape on the grounds that some on the site had recommended it. It seals very well, no leaks here in Fla downpurs, but I would not use it again. In the heat here it softens up and gets mushy and starts to change shape and emit droppings.

I read this a while ago at the Catalina Site. It seems that Butyl wasn't such a good idea in Florida because of the heat. You can find butyl caulk at the auto parts store. It is used for putting in auto windows. The only time I used it was to re-install the rear window in my pickup. I don't think I would use it to put in the windows on the boat. It is terribly sticky stuff to work with.
I'm sure Tim knows exactly what to use.

I haven't seen the groove in the portlight so I don't know, but you might be able to use O-ring material if the groove is the correct profile. There are a few standard cross section sizes for o-rings and you can purchase the material in bulk length. You can cut it to the length you need to fill the groove and glue the ends together with Superglue to make the exact length you need. www.oringswest.com has all the info you should need to determine if o-ring material will work. Nitrile (Buna-N) will be plenty good. No need for the exotic stuff and Nitrile is common and cheap. Nitrile material can be purchased at McMaster Carr or Motion Industries, or O-rings West. Mcmaster Carr calls it o-ring cord stock. It is available in round and square cross section.
Dan

jhenson · Post by **jhenson** » Sun Feb 27, 2005 11:09 am

Thanks,

I wasn't aware there was a replacement rubber for these seals available.

Joe

Figment · Post by **Figment** » Mon Feb 28, 2005 5:03 pm

Yes, autoparts places (specifically, auto glass places) supply the preformed black rolled-up bead of butyl sealant. But don't try to use it on Triton deadlight frames on anything less than a 95 degree day. I learned that one the hard way.

The product generally available via the automotive world is a semi-cured bead of about 1/4" diameter. This is such incredible overkill that it just makes things more difficult than they need to be. 1/16" or 3/32" would be ideal, but try finding that.

Hardware store butyl (generally marketed for gutter work) is much more cooperative, and comes in colors other than black if you look hard enough.

Post by **Tim** » Mon Feb 28, 2005 5:19 pm

Figment wrote:Hardware store butyl (generally marketed for gutter work) is much more cooperative, and comes in colors other than black if you look hard enough.

Yup. I had no trouble finding white at my hardware store. It is sticky and nasty stuff, but aren't they all? At least it works. Even the stuff in the tube creeps somewhat depending on temperature, but I've not experienced anything severe.

Allen · Post by **Allen** » Thu Apr 07, 2005 1:27 pm

Dan wrote:
I read this a while ago at the Catalina Site. It seems that Butyl wasn't such a good idea in Florida because of the heat.

From talking to Tim, it looks like Butyl was used on the ports on Kaholee. I recently removed them after about ten years. The butyl was still soft and pliable, removal just involved scraping it off and putting it in a zip lock bag. In fact it could be used again, amazing stuff! The heat issue seems to me to be a non-issue. Kaholee has spent the last ten years at Elephant Butte Lake in Truth or Consequences, New Mexico where the summer temperature is at least as warm as it is in Florida, and I never did experience a port leak.