Windshield gasket help

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Ironmike

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Installing new one tomorrow to rid myself of the corner leaks I've had.
Should I use any sealer, or silicone, and if so....where?

Never done a windshield before and really want it sealed perfectly. Any help is greatly appreciated as usual!
 
Yes seal it. No silicone! I used part# MS 4203 from NAPA. It is a butyl sealant that cures soft like the original. You will get people saying you must use urethane to keep the window in. If you ever have to remove though will be difficult.
 
In my experience w/butyl, the hotter the better.
 
Its a Demon. Looks to me like the bottom of the gasket just lays on the dash. I'm guessing that's where to use the butyl weatherstrip adhesive, but what about the actual glass in the gasket channel?
 
Man this is now confusing the crap out of me. All the controversial butyl vs. Urethane on the Web is enough to make ya crazy.

Windshield is out all the " pinch weld", if you want to call it that, is nice and clean. All I really need is SOME sealer to seal the gasket to the sheet metal. Then I'll fit the glass in.

Why would good Ole 3M weatherstrip adhesive not be correct for this job?

I need to get this done tomorrow. Will the Napa 4203 do this job properly? People say it will get hot in the summer and just "ooze away" causing leaks.
 
The butyl was used from the factory with windshields that had gaskets. Urethane was used on newer vehicles. The problem with butyl it is not an adhesive only a sealant so won't hold the windshield in place as well in a crash. But if you get hit that hard it's probably all over anyway.
The Napa 4203 is made for sealing windshields. It cures soft to be flexible with the gasket.

Weatherstrip adhesive is a glue only, it doesn't have any body to fill any gaps.
 
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I would use urethane on the gasket to pinch weld. Flow the butyl sealant before the lock strip. Or let a professional do it for 60 bucks.
 
Freezerman said:
The butyl was used from the factory with windshields that had gaskets. Urethane was used on newer vehicles. The problem with butyl it is not an adhesive only a sealant so won't hold the windshield in place as well in a crash. But if you get hit that hard it's probably all over anyway.
The Napa 4203 is made for sealing windshields. It cures soft to be flexible with the gasket.

Weatherstrip adhesive is a glue only, it doesn't have any body to fill any gaps.
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Thanks man. Think I understand better now. Definitely need something with body to fill in the gaps, especially the corners. All looks pretty good under there. Not even a hint of any rust, thankfully.

Doing the Internet thing, it seems like the urethane doesn't stick the rubber to painted sheetmetal very well. At least a couple guys had issues there. Will head to Napa tomorrow for the 4203.

Appreciate the help!
 
Ironmike said:
Thanks man. Think I understand better now. Definitely need something with body to fill in the gaps, especially the corners. All looks pretty good under there. Not even a hint of any rust, thankfully.

Doing the Internet thing, it seems like the urethane doesn't stick the rubber to painted sheetmetal very well. At least a couple guys had issues there. Will head to Napa tomorrow for the 4203.

Appreciate the help!
Click to expand...
Hence the professional annotation. You need a primer, an etch primer and cleanliness.
 
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I will be using urethane and letting my glass buddy do it. It won't leak, and it will be much stronger. I think it is better to use modern materials when you can.
 
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