Advice needed-Cabover window sealant

Well, thanks for all the good advice. I finished the job today. I used 3M WINDOW-WELD Urethane. After that, I replaced my LP Gas alarm so all is ready for travel again! David

turtletalk wrote:
Actually, I have only the glass out like taking a windshield out. I have used Butyl tape for replacing an entire window unit but this time have just the glass out. What do you think? I scraped off very gooey black stuff. David

Oh that makes things different! Very different - I thought you had the whole window out.
Toss out the previous ideas now.
Glass is held into the window frame with glazing tape. There have been many transitions in the methods for glazing windows.
Years ago they used to use black butyl tape, roughly 3/8" X 1/16". The size varies a bit. This stuff sticks really well, but oozes and the glass can actually move in the frame. The hotter it gets the softer the butyl becomes. It is still available and is still used in some applications.

What is more common now, especially in residential applications, is foam glazing tape. Same size, but it does not ooze and the glass does not migrate using this tape.

Tape is 2 sided - once the glass is in the frame, there is a trim strip to finish it off. Sometimes rubber, if curved corners, sometimes aluminum.

Ours also had the "very gooey black stuff" between glass and frame. If you have a glass shop nearby they may have the black mastic. I dont know what it is. I got some from local shop when I did our door window, thin with release paper.
I'm unsure-
butyl would seal but our front window uses a seal that pops in to retain glass-compressing the butyl tape to reinsert seal would be painful?

I have a fleetwood caribou 9E and had a small leak to, it ran down the inside of the window but the leak came from the running lights above the window. Just a thought to look at, I was thinking it was my window to.

Actually, I have only the glass out like taking a windshield out. I have used Butyl tape for replacing an entire window unit but this time have just the glass out. What do you think? I scraped off very gooey black stuff. David

Ditto on the no silicone.

Butyl is your best first line of defense when putting a window or anything else in.

But use caution when you buy the stuff. There are 3 different grades available.

1) Grey putty tape. This stuff is garbage and must not be used. It dries out, cracks and crumbles in a very short time. Trailer manufacturers love it because it is super cheap and remains pliable long enough to get their product into the consumers hands.

2) Poly-Butyl blend tape. Better than the putty tape stuff and a bit more in price but still not the best.

3) Butyl tape. The pure butyl tape is by far the best. You can stretch a piece of it like a rubber band, you can roll it up into a ball and form it to any shape you want and it remains pliable for many many years of use. This product is the most expensive but it is well worth a few extra bucks a roll.

As an example, last weekend I pulled the factory roof vent out of the bathroom of my 97 Topaz. It has been installed with the good quality butyl tape. I not only had to fight with a prybar to get it out, but also had a miserable time scraping it off my rubber roof before I installed a Fantastic Fan. It was pliable enough that I actually could have left it there and reused it to seal the fan, if it was intact. It stuck to my hands and my tools when I removed it. Great stuff, even after 16 years in use!
I sealed the outside of the flange of the vent to the rubber roof with Dicor seal leveling caulking. Again, great stuff. Might be awkward trying to use Dicor on a window though...

Butyl tape is generally the first "sealant" to use between the frame and camper body.

I use this, let it ooze for a month or two... Scrape the excess then run a bead of Geocel around the outside of the frame.

Do not use silicone.