I use 5200 for pretty much everything now, but Boat Life Caulk works well too. Never used 4200 but Im sure its good stuff based on the other 3m products Ive tried. Ive had to remove running gear that had been installed with 5200 just months before and its not *that bad*. I cant think of any reason you'd need to remove an exhaust port... if you use the proper sealant, you shouldn't have to re-do it in your lifetime.[/quote]
POST # 6
is a reason to take it apart and then there's the fact that I am taking them apart right now.. I just like to think ahead and the previous owner had used Silicone and that was not the reason for taking the flanges off so it must have held together pretty good..But I do have some 3-M 4200 and silicone...Guess it will be a game time decision..