Sorry, toddster, I meant I'd take the port out and start over.
Is sikaflex 291 like lifecaulk or should I stick with Lifecaulk?
I'm leaning strong toward doing that one port with caulk based on what I've read on this site. I love butyl but this one port is pesky. Thanks,
Jay
LifeCalk is a polysulfide, which is a weaker adhesive on metal and gelcoat. Polysulfides remain flexible and are easier to remove than polyurethanes after they cure. In my experience polysulfides will start to leak after a few years when used to seal metal against gelcoat on a large fixture. Sikaflex 291 is a polyurethane, which is generally a better adhesive than polysulfide. So, a polyurethane remains flexible, sticks a little better but is harder to remove when cured than a sulfide. I've started to bed deck hardware, especially if it is on non-skid patterns, with polyurethanes. I used polysulfide (LifeCalk) to bed my opening ports (Bomar) and have had no trouble after 10 years+. With these calk-type sealers you really need to fill up the voids and get some squeeze out to get a lasting seal. The hardware that secures any frame into an opening needs to be tightened properly to reduce movement as much as possible. That usually means for a port frame you're not over-torquing the fasteners, just getting them good and snug and fully coating them also.
A quick search of the makers (Boatlife, Sikaflex) or the terms (polysulfide, polyurethane) will pull up comparisons and recommendations for the materials.
