The previous owner of my boler
used a few odd things to reattach and or replace seam tape. They used duct tape, blk tar (my favorite!) and some white gooey stuff. It first I thought it was silicone or something but it did not harden...just stayed gooey.
Anyhow...after trying many things... I came across Goof Off
. Far different and way more powerful then Goo Gone
. And it worked on all of the above!