Replacing rear quarter window: Whats that black goo stuff? Do I need more?

CaifanSC

SCCoA Member
I just replaced my passingers rear quarter window today. Thing was cracked after a window shutter flew out the house and hit the 94 right at the window and shattered it. In any case, I replaced it with a spare window I had (spares rock!:D ) but I'm not sure if Im stupposed to add any of that nasty black goop that was sealing the old window. There was still much of that stuff left in the surface of the car and the other window I put there had some, but im not sure if I should add any. What is the stuff called anyhow? Where can I get it?

Any help appreciated. The window is installed now but i haven replaced the rear seats or the plastic panels so If need be, I can easily unbolt the window and add some of that stuff. However, its supposed to rain tomorrow and the 94 is now my daily driver since the 35th sprang a steering leak:( . ~~~ to do with these cars :confused: . Just cant win.
 
Mmm i'v replaced two of them, and both times I had picked up a roll of that from the store... it comes in a little bead u unroll and put along the edges....I forget what i asked for when i bought it tho, so I guess Im really no help to you other then, yes you can replace the tar
 
I just replaced mine during the new paint job. The local auto glass installer sold me some silicone sealer to use instead of the factory butyl tape (that black sticky goo). All aftermarket glass installers use the silicone. It also holds the glass in so you don't need the screws anymore, but I used them anyway.
 
NO SCREWS ?! whoooooah nice... thats gotta be so much easier then doin the screws, theres gotta be about 15 of um... But arent the bolts attached to the window ? yeh gotta cut them off ?
 
Cut 'em off? No, you just stick the bolts through the sheetmetal to install the window, and the glue-silicone holds it in. The studs are just left nut-less inside the sail panel.
Like I said, I reinstalled the nuts anyway due to my anal-retentiveness.
 
Silicone on glass? MMM, not me. At a minimum you need to use something that has some grip. Typically some sort of polyurethane caulk, not silicone. Nothing will seal as good as that butyl rubber material. Should be available at auto parts stores in various lengths. Roofing tar would work too but is a tad gritty usually.
 
Maybe it is not exactly 'silicone' I'm speaking about, but is stuff that the glass shops use specifically for that purpose. Its a 3M adhesive for glue-in windows, and it is rated as a structural adhesive: It supports a specified weight, so it is authorized as a glue for glue-in windshields. I used the stuff to re-attach the clips to the window glass on my 88 Cougar. Those clips are NEVER coming off!

And any glass guy will tell you that the factory butyl tape/goo almost always starts to leak after a few years in the hot sun, as well as run out of the gaps and drip down the sheetmetal. Just look at any Mustang or similar car that has spent its life in the Florida sun and heat, and you will see the black ooze of disgust working its way out the bottom of the 1/4 windows.
The aftermarket stuff will never leak or drip, but to remove it you need the wire trick..they won't just pop out anymore.
 
Yeah, that's not silicone, that's a urethane caulk. You need something like that because it never really gets hard, so as the car body shifts, it won't break the bond with the glass or the body, it allows things to move.

silicone won't do a good job. Found the 3m 8909 Window weld on e-bay. Probably not carried at the local auto parts store.
 
100 % silicoln doesnt get hard , it stays like a rubber for many years, I just got done using it in a rear window on my moms truck, that ~~~~ will hold the glass in just as good as the urethane caulk , anything I do that needs to seal water out I use 100 % silicoln, and have never had a problem, and since I am a maintenance man and run a hardware store ( that replaces glass ) I go through alot of it, and would know if It wouldnt work. Just figured I would chime in , sorry
 
Can't stay out of it

I gotta chime, too. My dad's been fixing wrecks since i was knee high, and it's become a hobby of mine. Butyl used to be the way. I don't know that the dry, clean surface (and many that aren't) exists that that gooey s**t won't bond to. Urethane has replaced butyl for a majority of automotive glass installations. Windshields in particular. Glass has become part of the structure of today's vehicle, and it's quality and bond to that vehicle are now critical to the protection of the vehicle occupants.
Butyl and urethane give fantastic adhesion. Urethane is considerably stronger than butyl, which is why it has replaced it.(roll over protection, in particular)

Silicone is a good gasket-maker. But i can roll it off with my thumb. There is little or no adhesion on many surfaces.
 
So in addition to the black stuff left in the surface, should I add a bit more? You guys said that urythane or butyl stuff should be avaialble in the parts store ?? (autozone/advanced auto)? Thanx...its alot of rattling when you drive w/o the back seat in the car...noisy f'er :p .
 
Any body shop can probably sell you some butyl, or tell you where to get it. Just let your fingers do the walkin! maybe measure the perimeter of the window (or bring the car) and see if the body shop will sell you a chunk instead of buying an 8 or 10 ft roll.

P.S. if you have any left over, it does a killer job sealing up tubes of silicone or caulk. You know, instead of trying to find a bolt that fits in that damn tip:) just make a ball and mash it on there.
Also, it can be cleaned off of most surfaces (including hands) with gas, thinner, or WD-40 with minimal effort.
Good luck
 
3m windo-weld flowable urethane available at most autoparts stores comes in a 10 fl. oz. cartridge
 
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