As the title states will RustSeal stick to Silkaflex 291LOT polyurethane marine sealant. I used the 291 between the seam of an 1 1/2" scale Train tender tank and its base and it ozzed out into the area I want to coat with the RustSeal. FYI the sealing surface is new sanded powder coat..

RustSeal will stick to the Sikaflex 291LOT. Since the sealant is cured polyurethane, it just needs a little surface prep before you coat.

Here is what to do:

1. Scuff the sealant area with 400 grit sandpaper until the surface looks uniformly dull.

2. Wipe down with KBS Klean to pull any sanding dust and residue off the surface, then let it dry completely.

3. Apply at least two thin coats of RustSeal. Thin coats are the rule here; thick applications can trap solvent and cause bubbling.

The recoat window is 2 to 6 hours between coats. Your powder coat is already sanded, so that part of the surface is ready to go. Just make sure everything is clean and dry before you start.

Before you get going, read through the full RustSeal Application Directions at the link below. The steps above are a quick orientation, but the directions cover temperature, humidity, dry times, and other details that can make a real difference in the result.

• RustSeal: https://kbs-coatings.com/rustseal

• RustSeal Application Directions: https://kbs-coatings.com/rustseal-directions

Thanks for the information and glad too hear this will work. The sealant is not exactly smooth as it was also coming up thru the rivet holes so do the nooks and cranny's need to be sanded as I doubt that's going to happen?

If the surfaces are clean, you should get excellent adhesion between the RustSeal and your cured urethane sealant. Scuffing is an insurance step.

Please reach back out with any additional questions.