How to install a rear window on a 71-73 fastback

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72HCODE

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yes correct the seal only wraps around the top and sides. its impossible to make it wrap around the bottom. there is a panel cover that rivets to fill the trunk area under the window so its impossible to get your hand in there or make the seal wrap around. so the seal sits open the bottom.

I did not put the foam tape at the bottom, the mustang article shows they did, i followed the body manual and it only showed tape around the top 3 sides.the rubber seal just sits on the trunk panel ledge. you can't even get sealant in there at the bottom it kind of made sense to me that any water trapped there would be allowed to drain out since there was no foam or sealant.

now my window had been replaced before so i did not have original materials to go by,, but when i did pull everything out you could see glue residue of where the foam tape and sealant was, the bottom of my window channel was clean and showed no evidence of any foam or sealant used at the bottom., that confirmed the mounting procedure for me when i installed the new window and seals.

 
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1971 Mach 1, Grabber Blue w/Argent stripes. Original 2V 351C Auto, Tilt, rear defog, Black Comfortweave Interior. Under restoration. Original colors, 4V 351C, 4-Speed, Spoilers, Magnums, Ram Air. All Ford parts.
Installed the glass today with the help of my wife. I have two questions at this point.

1) The directions say to slap the glass firmly to get it to fully seat. How do I know when it is fully seated?

2) The directions call for a butyl caulk to seal everything up. Where do I get the stuff and what should I expect to pay?

Thanks,

kcmash

 

72HCODE

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basically you slap the glass flat near the rubber gasket and feel for it popping in place a little deeper. go around the window you don't want to break the glass just a firm flat slapping/push to make sure its all the way in.

Laural sells this stuff

http://www.laurelmountainmustang.com/products/mustang-windshield-and-rear-glass-sealant-3m-bedding-and-glazing-compound?gclid=COeZ5oyYusACFZJr7AodU00Aqw

i remember i used a 3m type black sealant

something like this

http://www.handsontools.com/3M-08693-Auto-Glass-Urethane-Windshield-Adhesive-105-fl-oz-Cartridge_p_14707.html

you need 1 or 2 cartridges its about 12-15$ a piece. basically you want to fill up the window channel almost to the top, leaving 1/4" for the chrome trim, i think i filled the caulk to the Rivets on the clips for the chrome trim. use a tongue depressor to push it in and make it smooth. you will need to put sealant between the rubber seal and the top of the glass do this first. get the sealant ready with the caulk gun, cut the tip with a small hole then stick it under the seal on from the glass and get a bead in there it will smoots out on the glass got around all 4 sides, then come back and wipe the excess off, it will need more cleaning later with a razor blade anyway.

Oh and use thick painters tape and mask off the body around the window ledge so the sealant doesn't get all over the paint outside of the window channel.

so once the rubber to the top of the glass is sealed with goop, then fill the sides of the glass.

Now before you do all this Give a last inspection of your headliner and sail panel trim inside the car to make sure it looks good and the seal isn't catching something wrong. you can still pop the glass out now if you have a problem and start over, once the sealant is in it is much harder to start over.

I made a slight mistake on my car when i installed my sail panels, and didn't catch it until much later after i had glued everything in.

 
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I need to do this my original seal is badly cracked and leaks. The glass shop in the area told me they will do the job if I buy the replacement seal. they quoted me a price of 100.00 to do it, after reading your post I think that's a hell of a deal. Any suggestions or info I should pass on to the installer would be helpful thanks.

 
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Since I am fairly new to the Forum coming up on a year I think I read through the entire thread.

Do you guys realize that the factory had a little over one minute to install the rear glass, lol. I agree with all of the cleaning of the window channel and prep of the studs and getting the rust and any holes taken care of. I also take a body hammer and dolly and flatten out the sealing surface as best I can and if any spot welding flash is sticking up grind that off. If you don't get paint back on this area it will rust.

Go around the opening and chamfer the edge that the rubber seal has to pull across, I like to use a file it is smoother than a grinder. This needs to be done before paint. This will make pulling the gasket into the opening much easier.

It has been my experience, I put my first windshield in in the 60's so did a few, that if you put small amounts of sealer it is better than filling up the whole channel. The gasket is the seal and sealer just closes up any small imperfections in the fit.

When I put the new rubber seal on the glass I put a very small bead of sealer in the gasket where the seal hits the edge of the glass. I do use 3-M sealer non hardening type. DO NOT USE 3-M WINDO-WELD #08609 to seal the gasket. That material is for installing a glued in window like the front windshield without a seal. 3-M 08509 is a no hardening bedding & glazing sealant and is available on Amazon or at O'Reilly auto and is correct for this application. http://www.oreillyauto.com/site/c/detail/MMM0/08509/N0468.oap?ck=Search_N0468_-1_-1&pt=N0468&ppt=C0209

When I cut the tip of the tube I only want a very small opening 1/8" dia. volume is not the answer to a great seal. The glass part of the seal will probably not leak without any sealer at all since it is smooth. That is why I put just a small amount for insurance.

You need a big table with carpet on it to protect your glass especially if has the expensive rear window defogger.

For the nylon cord I like the woven type and not over 1/8" in diameter. As stated in the thread and and in the Ford install info you put the cord in the rubber on the outside and meet in the middle at the bottom. You can make you some pull handles if you want but usually not needed. You do not need to go to far inward on the bottom with the cord since when you set the glass in place you can insert the rubber seal over the cleaned and prepped body.

This is a two or three man job for sure. They sell the suction cups at Harbor Freight to make it easier to lift and also the tools to pull the rubber in or cut an old windshield out.

You and your friends can set the glass into the opening and slide the bottom edge over the metal flange. I do sometimes put a small amount of sealer on the flange and spread it out with my finger, outside surface only. In the corners is where the metal is usually not so flat. Easier to do now than after glass is in and you don't pull the rubber across this area you slide it on.

I take some wood dowels about 3/8" dia. and grind a flat on each side to make a tool to massage the rubber seal with. You can also use some of the plastic trim removing tools.

To get the two bottom rear corners of the gasket through the opening you can use one of the small metal hooks with a handle like a woodruff key puller. Be very careful not to contact the glass or tear the rubber.

Once you have the bottom rear in the opening then push the glass back and wiggle it into place. Have your buddy or buddies push to the rear on the upper edge of the glass/gasket as you start to pull the cord. I like to pull both sides together to keep the glass centered. Your buddies can wiggle and push down while you pull, suction cups help.

The two top corners might be a little tough to pull in use your hook to help the rubber around the corner and then finish pulling the rubber in. Use your wooden dowel tool to massage the rubber in any place that looks out of place.

Now you can take your tube of 3-M 08905 bedding & glazing sealant and go around the outside of the rubber. Lift the rubber with the wooden dowel and put the tip as deep in as you can and shoot a small amount of sealer in. You DO NOT want to fill up the channel only put a small amount of sealer to fill the imperfections that the rubber does not seal.

Clean up the rubber with solvent and now you can install your trim. If you were to ever see them install the trim on the assembly line you would freak out. Again a minute or less to install for the line worker. You are not in a race so take your time.

If you have a window that is leaking and you cannot find the spot do the following. Close up all the windows and trunk and vents. Take your airline inside the car close the door and open the nozzle wide open and have someone put water around the window frame and look for bubbles. It will surprise you how this will show up a leak. A little bit of positive pressure inside will make bubbles.

This sounds like a long task but it will be done in a few minutes as long as you have helpers.

I know others have said you cannot use too much sealer but it is like putting a gasket on your engine a small amount fills the imperfections and closes the gaps and does not make a mess. It also makes it easier to put the trim on and get off again if needed.

I am one of those people that feel you should not wash your car with a hose or pressure washer unless it just went through a muddy field and is caked with mud. A good clean bucket of water and micro fiber towel and frequent cleaning of the towel is all you need. When you use a hose you fill all the gaps and openings with water you just keep the enemy RUST going. The water gets inside the doors, quarter panels, cowl rubber gaskets on doors trunk and windows and tail light frames which is not good. Most of our cars never see rain unless we just got caught out there and no where to hide.

Just my thoughts and experience over the years.

David

 

JagDaniels

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Hi, greetings from Germany.

I got an 1972 Ford Mustang Grande. These Cars are pretty rar over here, but i enjoy every minute sitting and driving my car.

My car is ready for the painting in the originial color bright blue, but i want do renew the rear window. I sometimes don't understand all words in a correct way :) ! But may you can help me...

This Foam Tape is only needed when you driving a fastback version ?

Thanks for your answer and support,

i only used the german forum of mustang inside community and i love to join the original american homebase ! Thx for this awesome forum !

 
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Hi, greetings from Germany.

I got an 1972 Ford Mustang Grandé. These Cars are pretty rar over here, but i enjoy every minute sitting and driving my car.

My car is ready for the painting in the originial color bright blue, but i want do renew the rear window. I sometimes don't understand all words in a correct way :) ! But may you can help me...

This Foam Tape is only needed when you driving a fastback version ?

Thanks for your answer and support,

i only used the german forum of mustang inside community and i love to join the original american homebase ! Thx for this awesome forum !
Yes that is correct. Ford added the tape to try to get a better seal. You should remove your rear window and clean and even out the spot welds and paint with the window out to get good rust prevention. Then put the window in with a new rubber strip and maybe new trim clips.

David

 

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