Sorry, 10000th TTop seal thread. Couldn't find an answer for my question.

I've seen it been suggested to use butyl rope instead of weatherstrip adhesive in the t top channels.
Seems like it would make it much easier to replace the seal again in the future, but would the seals shift around without adhesive?

 

huh, never heard that before. the butyl might work if you are careful when removing the tops. I wouldn't use it tho. I'd go for a permanent factory type solution. my factory are 32 years old and still working great, so its not like you have to do it all the time.

 

That's true. Mine were 37 and the T bar was rusted. Made me think there would be more rust underneath but turns out that everything else was perfect.

 

In the GM T-Top sealing service manual they say to use butyl covered foam rope in some areas for extra sealing, but to glue the seals down.

 

Where is the rope sold? GM??

 

In the old gm ttop seal kits, there were updated instructions and a combination of things were used to seal the rubbers to body. Just depends on location.

 

 

Thank you sir.

 

The 3m adhesive is a sealer and not useful for filling the gaps and voids. That is here the butyl rope comes in.

 

It seems to me (and from what others have said online) that laying thick beads of 3M 8008 doesn't work very well to glue things down, but yet GM specified in the water leak manual to apply it in such a fashion under the lip of the weatherstrip channel. I think that friction alone is what holds the seal in place for the most part, since pulling my old weatherstrip out of the channels was only about as difficult as pulling the new seal out after dry fitting it, other than in the corners where they applied a thin coat of adhesive in the middle of the channel from the factory.

Hypothesis: the adhesive acts only as a filler between the lip of the seal and the lip of the channel and that butyl should also work in that application with the benefit of being removable. Ideally the corners should still be glued down with a thin coat of adhesive, but I did not apply any in my experiment.

Method: I ended up using about 10 feet of tuff-tite butyl rope in place of the adhesive as an experiment. I put small 3/16in beads of butyl under the outer lips of the channels as well as where the manual calls for strip caulk. For the center bar I put 2 beads on the inboard side of the channel. I used a heat gun to get the butyl nice and soft the pushed the weatherstrip into place. It seated fully, and fits correctly under the channel lips.

Short Term Observations: Seems to work fine, the weatherstrip stays in place when the doors shut and windows move as well as when the tops are removed and replaced. I don't have any unexpected leaks which would could be attributed to the use of butyl. The only leaks I saw were between the weatherstrip and the window glass corners, exactly where the old seals leaked. I was able to adjust the windows and got it down to only leaking little dribbles.

Conclusion: buy a hardtop

 

I just discovered something else that may come in handy when working on a seal for my 545. (below) This stuff is pretty cool. You place it on a surface, and it dries to form a pliable gasket/seal, and you can form it to what you need. I used it for that, and also for bonding a plastic air vent to the firewall for cabin fresh air intake. I could see this coming in handy to bond things to the T-Top, like the drip edges. It can form a permanent bond, but it is still removable.

Permatex 81158 Black Silicone Adhesive Sealant