Car body sealant identification question

[bushmechanic]

The vehicle in these pictures is a convertible 1996 Jaguar XJS. The sealant pictured was applied at the factory.

This sealant is under the top rubber seals, appearing to clog the end of the metal channel naturally created by the shape of the windscreen frame.

It was also applied before installing the A pillar seal attachment rails, where it was squeezed out sealing the edges when the part was screwed down.

Now, this stuff feels like silicone. This car was likely built in 1995, and it's just as soft, transparent, and annoyingly rubbery as if it was applied yesterday.

There are a number of seam sealers that are clear, however, and I find it hard to believe that any silicone product would level this well and be production friendly. All the cars would smell horrible for a month after assembly, and silicone is about the hardest thing in the world to level.

So, what the heck is this stuff? It didn't stick to the rubber to the point of destruction. I know that well. And that's got to be important.

I've got a fortune in replacement seals, here, and I don't want to damage them or have to remove them after installation.

Just to note again, this sealant is very soft and rubbery, very much like silicone. If I didn't know how nasty silicone is, I'd assume it was indeed silicone.

 

[Zeke]

If it walks like a duck and quacks like a duck....

There is also a clear polyurethane. It will stay supple but it won't squeeze and bounce back like silicone. I think it also sticks to rubber. And it too stinks when new. So back to the duck.

 

[Bill Bowman]

Most likely NOT SILICONE. Silicone has corrosive properties that Jaguar and most other manufacturers don't need help with. It's still used, and usually real sticky and messy. I get it every where in the shop when working on a car with this type dum dum.

I think it's there to seal out wind noise and moisture also. You probably won't find the exact same dum dum to replace this stuff, but I've had good luck using 3m spagetti or strip caulk product. Bill

 

[ssbtech]

Reminds me of the time the window shop broke the clip off my A-pillar trim and stuck it back on with silicone.

Yeh, like I was going to let them get away with that.

 

[RPH]

Urethane is most likely the base. See drums of it all over the assembly plants. Some are robot applied and others are hand sealed. Go to a good body supply shop and ask for a seam sealer.

 

[bushmechanic]

Yeah, this is what I figured was the case. It had to be some kind of seam sealer.

The first two things that came to mind:

http://www.oreillyauto.com/site/c/detail/MMM0/08405/N2356.oap?ck=Search_N2356_-1_2246&pt=N2356&ppt=C0171

http://www.oreillyauto.com/site/c/detail/MMM0/08500/N2356.oap?pt=N2356&ppt=C0171

Since Amazon has this stuff cheaper, and the only trustworthy body shop around here pretty much only handles welding and paint, I think my best choice is to test out a few products to see which one does what I need without damaging rubber.

I'm still deciding whether or not I should mess with it. I did tear some removing the seal, though, but only because I grabbed the seal really tight. Once it was off, the stuff fell right out of it.

Also, I'm left with a rough edge there. If this **** is meant to blend with the rubber shape a bit, I've got to pour more in there. Likewise, it may be long-lasting stuff, but I wonder if it needs replacing anyway.

I honestly think it's there to help bolster corner sealing around the end of that channel. The rubber seals themselves featured a black tarry sealant to help join them, which I have yet to completely identify. It peeled right off the rubber, just like the clear ****.

I've just got to make sure I don't stick anything to that rubber that's going to damage it or become a permanent feature.

Hell, I don't even know if I can get the clear stuff out of that corner. I'm afraid to start, only to find it's impossible to finish without damaging the paint in a critical area.

Anywhere else on the car, sure, I'd rip it right out. That's the most important sealing area on the whole vehicle, though, so I want to get it right. I'm not taking it to a "professional" because none of them around here are worth a damn.

Well, there's one, but he's a metal and grinding wheel man. I'm not sure he knows his polymers any moreso than I do. I'm going to ask him, but I obviously have to wait for a nice day at this point, given the total lack of sealing surfaces on the vehicle.

 

[bushmechanic]

Most likely NOT SILICONE. Silicone has corrosive properties that Jaguar and most other manufacturers don't need help with. It's still used, and usually real sticky and messy. I get it every where in the shop when working on a car with this type dum dum.

I think it's there to seal out wind noise and moisture also. You probably won't find the exact same dum dum to replace this stuff, but I've had good luck using 3m spagetti or strip caulk product. Bill

Given the fact that everything up there looks entirely brand spanking new, I figured it couldn't possibly be silicone, especially since it was flattened out and there weren't little silicone "strings" all over the place.

That stuff is nasty.