Not sure what silicone 732 is and why you have all that blue tape holding the barrier on? What you need to do is remove the old barrier and remove all the original black 3M sealer which is extremely tacky and somewhat difficult to remove. However, once you discover how to remove it it gets easier. Once you have like a golf ball sized chunk rolled up you actually use that as a magnet to get the rest of the stuff off by "blotching" the old seal. Again, it's difficult and you need to repeatedly go over and over the old seal until it lifts off. Once you have the old seal off and everything cleaned up just pace a new seal along the old path, on the door, not the barrier, as you will see where the old seal was as it contours along the door. You don't need a new barrier unless it has a tear or hole in it. Press every square inch of the barrier back on the new sealent and you don't need tape to hold it and it doesn't need to cure. This "732" stuff that needs to be cured, not sure you should use that. This 3M stuff, I forget the product # can be had at the dealer, or, I did see the EXACT same stuff at Advance Auto type auto parts stores. If anyone wants the product # I can look in the garage.
I think you read at least some of it wrong. I didn't mention anything about using double sided tape. I indicated no tape is needed to hold the barrier on while it's curing because using the 3M stuff requires no curing.Yes each into his own here but I think where the problem comes in here with this failure on the barrier is from previous work someone has performed while having the door panel off and not correctly re-installing the barrier. The 3M factory stuff is plyable and meant to be removed and re-used if needed. Example: if you need to remove the door panel for some reason and work behind the barrier you can carefully, slowly pull the barrier away from the door and place it back without issue. My guess is using the 732 stuff that needs curing would require a total re-do if removed? The factory stuff does not fail if it was installed correctly and it will never break down for no reason. I had an issue with my 2003 right rear door leaking and discovered the dealer never installed it back thoroughly. If done correctly and one takes there time to install it completely then this 3M product will not fail. Also, if you have "sopping" wet footwells I would remove or at least lift the carpet up back there where it was wet and let it dry out and maybe even spray something to kill any potential mold that may have grown under the carpet. Maybe I'm just being anal but thinking logically of at least what I would do.2 things, first if Im reading your post correctly youre saying that you should use the 3M stuff instead of the silicon and its the same exact stuff they used to build the car. If thats correct, then isnt the same thing going to happen again?
Second, silicon is waterproof and Im pretty sure itll last ages longer than the double sided tape that youre referring to.
To each his own but when I do this and its going to be soon because I just found my back foot wells sopping wet, I want a permanent fix so I dont mind having to let it cure nor do I mind using the painters tape to hold it in place until its done so.
I may have read your post wrong. I appreciate you posting an alternative approach but to me I want something thats gonna last longer than it did from the factory. Silicon I know for sure will do that.
Do you have a BMW part number for the sticky stuff? If you are in NH, wanna come down and help me with my door? I could use your expertise and experience with this repair. Dinner/libations/more on me .BMW sells their own, and it's much better than the 3M I've used previously. I've got hundreds of these repairs under my belt, and not a one has ever leaked. As I said, the key is using a heat gun to activate the butyltape. Just applying the tape and setting the vapor barrier in place won't necessarilly fix the issue every time.
You're going to be hacking away at that silicone w/ a razorblade for some time when you go to cross that bridge.
Agreed, but at least I know FOR SURE that it will not leak again. As I stated before, how often do people need to go back into their doors for a repair OTHER than a leaky vapor barrier......You're going to be hacking away at that silicone w/ a razorblade for some time when you go to cross that bridge.