Windshield install sealant

[fusion]

I'm installing a new gasket and windshield into my 280z.  I've read conflicting information on using sealant or installing dry.  I'm leaning towards using the sealant to ensure no leaks.     This is the sealant I purchased:  https://www.crlaurence.com/All-Products/Automotive-Windows-%26-Supplies/Automotive-Glass-Supplies/Glazing-Adhesives/Epoxies%2C-Sealers%2C-Urethanes%2C-%26-Adhesives/CRL-Black-Windshield-and-Body-Sealant/p/CRL7708

 

What's the best way to install with sealant?   If I install into the pinch weld groove on the gasket, I'm afraid it will be extremely messy when the rope is coming out of the groove during install.  I also wonder how the lube (soapy water or Windex) will affect it. 

If I apply it to the pinch weld, I'm worried that it will smear all over the gasket flap when the rope pulls it over the pinch weld. 

 

Maybe the best method is to install dry and backfill sealant under the gasket flap where it meets the body?

 

I've gone to great lengths to get the car extremely nice and don't want to have a disaster on my hands during the install.

 

Any thoughts appreciated.

Edited February 20 by fusion

[Sanchez]

I asked a buddy of mine (he’s an auto glass maker for customs and does a lot of windshield repairs for insurance) when he brought over some tools to help pull my glass from the Z. His response was to do it exactly the way it was done from factory. That would be dry install using a quality window seal. His reason was that some of these older unibody vehicles are designed that they tend to flex around the pillars, and the heavy duty sealant that is used for glass install can be hardened to the point that when the chassis flex’s a bit it can crack the glass. Now depending on where you live or the cars purposes you may have flat roads all the time, but in the Midwest I can definitely see how some of these potholes on the road could easily cause that to happen.

[fusion]

Thanks man.  I had read that Nissan did use sealant from the factory, but it wasn't super clear.  Also the sealant never hardens up, it remains soft, or at least it's supposed to.  

[tube80z]

1 hour ago, Sanchez said:

 heavy duty sealant that is used for glass install can be hardened to the point that when the chassis flex’s a bit it can crack the glass. Now depending on where you live or the cars purposes you may have flat roads all the time, but in the Midwest I can definitely see how some of these potholes on the road could easily cause that to happen.

 

A friend built an endurance car (Chumpcar/Lucky Dog) and was going to use a new Nissan gasket.  I talked him into gluing the windshield and was amazed at the results.  The difference between this and a normal gasket was the same having a strut bar or not.  This car has been used hard, ridden some large curbs, and never cracked a windshield.  I'm not saying it can't happen on the street but I'll be gluing in my street car's windshield when we get to that point.

 

Cary

[Sanchez]

Sounds like it might be able to work both ways. I would assume with some additional chassis bracing it would be less likely to flex in that area, or the Z might be pretty rigid in that area already. It would be interesting to hear from a couple other people who have gone the sealant route and hear what kind of sealant they used (how hard/soft it is) and whether or not they had any sort of other chassis bracing done (stitch welds, cage, strut bars, etc).

 

If I remember the Precision brand window gasket has an issue with gaps in the corner and I could see sealant being helpful in that case, but my 50yr old original gasket was still pliable with no leaks and held the chrome trim fine when I removed it (not a spot of rust in the windshield channel either).

 

I think I remember a thread not too long ago about the possibility of “frenching” the windshield by having glass made a little larger in the dimensions and deleting the gasket entirely for sealant. It might have some more information about using sealant.

 

If it turns out nobody is having an issue with using sealant than it’s probably just down to dealers choice.

Edited February 22 by Sanchez

[tube80z]

On 2/22/2024 at 8:54 AM, Sanchez said:

I think I remember a thread not too long ago about the possibility of “frenching” the windshield by having glass made a little larger in the dimensions and deleting the gasket entirely for sealant. It might have some more information about using sealant.

If you want to do a modern flush mount look this is probably what you need to do.  I'm half-assing it with a different method for my car, at least at first.  And that's gluing the windshield and then using RTV to fill the gap and smoothing it.  I saw this back in the 80s and 90s on a few of the IMSA cars.  I asked a pit member how they did this and that's what he told me.  I'm also thinking about a 3D-printed rain gutter bridge to make air flow down the side of the car better.

 

Cary

[jhm]

@fusion, FWIW....I've done my last two windshields the way @Sanchez recommended (no sealant).  Haven't had any leaks with them.  Once it's in, it's key to "massage" the gasket in order to ensure that the gasket corners are all tight and filling the corresponding metal corners fully.

[fusion]

Thanks everyone for the comments