windshield install time!

stangman16

Active Member
Nov 16, 2004
640
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San Antonio, TX
Just need to know what type of windshield sealer to get and where to get it at for my '66 Mustang..? I have the gasket installed around the windshield and I cannot wait to get it in. I just forgot to buy the sealant. :nonono:


Also, I'm anxious to drive the car after having done the cowl vents and having finished my EFI conversion. I'm curious if after I install the windshield, and temporarily put on the headlights & wipers, will it be okay to drive it around about a mile or so without having the cowl fender to apron extensions welded on and with no hood? I plan on painting the engine compartment here next and I was going to plug weld those on last...
 
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I have worked as a glass technician for 5 years and never used sealant on a gasket set window. I WOULD FIRST GET YOU SHIELD IN AND PATTED DOWN TIGHT AND THEN CHECK IT WITH WATER TO SEE IF IT LEAKS BEFORE YOU HAVE A MESS ON YOUR HANDS!!
 
The guy that owned my car before me replaced the front and rear weather stripping and did not use sealer...when it rained outside it rained inside as well! I could see the water flowing around the pilars when I drove in the rain. Wet carpets suck!!! The irregular contours created by the spot welds along the window openings create dead space for water to seap in. You'll definately need window sealant.
 
The guy that owned my car before me replaced the front and rear weather stripping and did not use sealer...when it rained outside it rained inside as well! I could see the water flowing around the pilars when I drove in the rain. Wet carpets suck!!! The irregular contours created by the spot welds along the window openings create dead space for water to seap in. You'll definately need window sealant.

Agreed the tolerances on these old girls are not up the today’s standards you will need the sealant.
 
DO NOT use the "window weld" silicone stuff.

Use 3M bedding/glazing compound. Very messy but it never gets hard and will not "glue" the windshield in. Use LOTS and LOTS of it or you will be pulling the glass back out and doing it again. Ask me how I know.

You MUST use a sealer. There is NO WAY it is going to seal without it.
 
You have to use sealant

You must use sealant. Do not use any silicone, as it will eventually shrink and cause more leaks.

Use 3M bedding/glazing compound or butyl windshield sealant. I have always used the butyl because that is what was on the originals, but it is nasty stuff. NAPA carries the butyl sealer in a caulk gun tube.

Anybody that tells you not to use sealant has not put a windshield in one of these older cars with this type of gasket. Newer windshields are different.

You will also need to remove the gasket from you windshield and put sealer in it before you put the windshield in the car. Or you can probably use your caulk gun to get a good coat of sealer in between the gasket and the glass BEFORE you try to drop it in the frame.
Here is a link on how to remove your windshield, but it has a good illustration at the end of the gasket and the windshield.

http://links.vintage-mustang.com/FAQ/window_removal.html


I would suggest looking for some more instructions on this - the way I have done it is to make sure the seal between the gasket and the glass is good (with sealant) - then run a cord around the groove for the body flange with a couple of extra feet exposed), fill the groove with sealant, set the windshield and attached gasket on the body flange, then use the cord to get the inside lip of the gasket to seat inside the flange.

I always put 3M blue tape on my headliner around the gasket, because this butyl is nasty stuff.

Here is another method (references the rope trick)
http://www.mustangmonthly.com/techarticles/mump_0403_classic_mustang_glass_replacement/index.html

I have done a rear glass this way, but I have gotten the rope trick to work better for me.