Rear window installation

[66FBCharger]

How does the back glass go in on a 69? Is it set on butyl tape or does it have a gasket like the windshield?

[StockMan]

Its actually glued in but many use the butyl strip.  When using either be careful that you press the glass down so that you can fit the trim.  I found that using the butyl worked well.

[Patronus]

It was my understanding you use the tape and sealant?

[Drop Top]

Tape will never seal right. Then when to have to take it back out to fix it. Its going to be a big mess. It shoud be glued in with urathane. You can buy it from auto glass companys for about $8 to $10. For what its worth have it installed profesionaly. Should cost aroud $50 and they will fix it free if it leaks. After you went to all the work fixing rust. Do you really want any more trouble with it now. I've been restoring these cars along time and I still pay to have the front and rear glass put in. I don't need the extra worries.

[doctor4766]

Butyl tape (with the wire running through it) is the period correct way of refitting the rear glass.
The wire is connected to a transformer and the current heats and "melts" the tape while the installer presses the glass into place at the right height.
Many of the original "heat seals" from this era dried out and went hard, giving the impression that the glass was glued in.
These days, with the advent of polyurethane adhesives, many installers choose to substitute polyurethane for the butyl tape as it's cheaper, easier and lasts longer if correct proceedures are followed to fit the glass using this method.
Either way is acceptable IMO.
I chose to fit my own rear screen using butyl tape as that's how it would have been done 40 years ago and yes, it does seal right. I made absolutely sure of that, and you don't need any other sealant to go along with it if you know what you're doing.

[Drop Top]

Once the rear window is installed you can't tell how it was installed. The origanal type of tape will dry out again and have the rust problem all over again eventually. In fact here in Calif. I have been told its not leaglle to use tape any more. Useing newer methiods is not allways such a bad thing. I used to be hard core old school and still am to a curtain degree. But I have changed in a few ways. Like I don't use lead for filler anymore enless the customer insists, I now use 3M panel bonding adheassive where I feel its safe to use and I use polyurathane to install front and rear glass as needed. Unless there is a rubber seal that needs to be used.

[Mike DC]

 
Just curious - is there a problem with using modern urethane on bare (no painted black edges) glass? 

I seem to somebody once saying that modern urethane sealants couldn't work for a 2nd-gen front windshield glass even if there was enough of a steel lip around the opening to try it. 

[doctor4766]

The black ceramic paint that is around the edges of modern glass serves to not only mask off what you see but also to reduce or eliminate UV breakdown of the adhesion of the urethane to the glass.


The origanal type of tape will dry out again and have the rust problem all over again
No, not true. Butyl tapes used these days btw are far less likely to dry out and go hard like the original style, however if you live in a hot climate they do tend to soften in the heat and can "sink" a little and ooze out around the edge of the glass becoming a bit unsightly sometimes.
There is a cloth retaining strip fitted on the butyl tape which some fitters remove. It should be left in place in order that the ooze factor is minimised.