Mach 1/Fastback rear window replacement

In early October, I picked up a 71 Mach 1. I have spent the last couple months evaluating what the car needs, and have been working through that list - Most things mechanical I can do with little guidance. One thing I found was that the rear window did not have a gasket - the previous owner used adhesive to install the rear window. To his credit, it didn't leak, but I think it looked bad on the inside.

So I decided to tackle this - I did find a few good threads, but wanted to see if I can pick up any additional tips or pointers before finishing the job.

I stated by taping around the trim to protect the paint from accidental scratches. Here I have just removed the bottom trim. the rest cam off with no problem. It was not held on by clips as much as the adhesive used to hold the window in.



Exposed the black adhesive and starting to pull it out a piece at a time. Looks pretty ugly.



Finally got the window out and continuing to clean up the old glue. I was able to clean this out in about a half hour - not as bad as I thought it would be.  I was worried about cleaning the adhesive off the headliner, but it pulled out without much trouble. Headliner is not glued to the top ledge so I believe that need to deal with that.



Here my glass is cleaned up with the new gasket around it. String is set in the groove based on the threads I found on the forum (Thanks!)



Questions I have for the more experienced folks here:

• The headliner only has about 3/8 to 1/2 inch of "fold over" the ledge. Are there any recommendations on adhesive for the headliner? Any tips for application?
  
• I've read that many put closed cell foam tape around the sides and top of the opening - if I plan on using a light bead of sealer around the gasket in the channel, is this still required?
  
• I have been tackling this myself - is a second person a necessity for  the installation?
  

I'm open to any coaching or suggestions - Thanks in advance!

Jim

Well, I did mine a few years ago.

To help you out I suggest the following.

1) Make sure you have the lighter gage trim retainer clips around the rear window.  There are 2 types that look similar, but the thicker ones are for earlier model cars with stainless window trim versus ours with aluminum trim.

2) I used 3M Weatherstrip Adhesive to bond my headliner around the rear window lip and the side tack strips.

3) Yes, use closed cell foam tape around the window opening.  Your window gasket will cover it up when you load the window and pull the string.

4) I did mine by myself.  A second person is good if available as it is tough to hold a beer while pulling the string.  Actually they can help set the window from the outside while you pull on the inside.

5) Yes, after the window is in, apply a bead of butyl sealant around the window and under the top "flap" of the window gasket.  (The body assembly manual has good pictoral of how it all goes together.)

6) Don't overfill your remaining trough as it will be tough to get the trim to seat.

As I said, the advice on this forum and the instructions in the body manual are a great help.

https://www.7173mustangs.com/thread-how-to-install-a-rear-window-on-a-71-73-fastback?highlight=rear+window

kcmash

I have to ask, are you using "string" or small "rope"? The string you are using looks a bit small. I had to crank on my rope, especially around the corners. I think I used clothes-line rope for mine. My ledge was also 3/8" to 1/2" and you have to kind of center the window so it is a good idea to have somebody watching from the outside. And FOR SURE get the more flexible window clips, there is a BIG difference between the stiff ones and flexible ones. You may also want to re-do your sail panels at this point because they should also fold into window channel. Good luck, rear windows are never fun!! I did mine twice!!

I am using nylon string - Is there a consensus that it should be a heavier product?

New sail panels are in the plan - I have them ready to go.

I have to ask, are you using "string" or small "rope"? The string you are using looks a bit small. I had to crank on my rope, especially around the corners. I think I used clothes-line rope for mine. My ledge was also 3/8" to 1/2" and you have to kind of center the window so it is a good idea to have somebody watching from the outside. And FOR SURE get the more flexible window clips, there is a BIG difference between the stiff ones and flexible ones. You may also want to re-do your sail panels at this point because they should also fold into window channel. Good luck, rear windows are never fun!! I did mine twice!!

Click to expand...

Where do you get the more flexible window clips? I didn't know there was a difference. Ryan

Speaking of sail panels - I was just looking at the interior assembly manual, and it does not appear to address sale panel installation. I am wondering about the top front portion of the new panels - do I just fold the loose fabric under the top edge of the panel? - I'm wondering about the upper part between the window corner and the quarter window.

I understand that the portion that aligns with the window should fold over the window edge, similar to the top/headliner.

Hopefully I'm describing that well enough.

We beat this subject up bad recently.

I would never use the foam tape on window or the drip rails. It was used by factory to make it cleaner and easier for them not better.

You should have worked on the flange around the window some to make as smooth and flat as possible.

Put a very small amount of 3-M sealer in the channel the glass sits in. Then a small amount on the bottom edge of the window opening.

Yes you need another set of hands so you can sit the window and rubber in easily.

You might need to cut you some 1/4" wooden dowels to use to massage the rubber some. If you use metal might chip and break the window.

After you get the window in have someone help you go around and lift the rubber and put a very small amount of sealer between rubber and the window flange.

3-M contact adhesive to hold headliner in place works.

See if you can find the old posts I put the part numbers and info on the 3-M products in it.

I got the window in last night. Prior to setting the window, I did make sure the flange was clean and flat. I was considering the foam, but in the end decided to go wiithout.

I did end up using a slight heavier rope to pull the rubber lip inside the car. That went pretty smoothly. I am going to go around the rubber with 3M sealant 08509, then install the trim and clips later today.

Thanks everyone for the advice

Jim

Sorry I didn't get back to you sooner. I forgot how I ended up with both the stiff and softer clips. I'm pretty sure the "stiff" ones were CJ's cheap ones, so if you get the ones from NPD or even your local Napa has the Ford correct ones. Just compare a couple different ones and go with the springier ones. You can tell when they are the good ones.

No problem - As it happened, I did use the ones from CJ, and had no issues - except, the package was short 2 clips! Luckily, I had 2 good ones on hand so wasn't a problem.