Review on 🚤 High-Performance 3M Marine Adhesive Sealant Gallon for Superior Boat Repair and Bonding by Rick Rogers

This product, like all 3M products, is excellent. I used it to reseal the leaky joint between wheelhouse and deck. The previous seal/gasket has dried out, shriveled and cracked. I cut it out and filled the grout 4000. I cleaned the area with acetone, masked the grout and applied 4000 with a caulking gun. The sealant spread smoothly and completely filled the seam, easily sealing the leaking seam. This product is waterproof, so cleaning will be messy if you get it where you don't need it. It is not smoothed over with a wet gloved finger, but simply smeared. Apply just enough to fill the joint and no more. Small excesses are "tidy up" when removing the masking. I've applied 4000 to a joint almost forty feet total and the cure time isn't fast enough that I can't just pull the tape out without pulling out the sealant. This made an attractive seam and eliminated the leak. Unlike 5200, 4000 does not dry/harden to the point where it needs to be sanded down for removal, but can later be cut with a knife if needed.