Features:

  • 3M Marine Adhesive/Sealant 4000 UV
  • One-part adhesive sealant that cures to form a firm, rubbery waterproof seal
  • Superior UV resistance properties makes this an ideal cosmetic adhesive sealant
  • Resistant to weathering, saltwater, and stresses caused by joint movement
  • Seals between mechanically fastened joints on wood, fiberglass, metal and most plastics above and below the waterline
  • Its superior UV resistance properties make this an ideal cosmetic sealant
Worth the money, get it and done

Love that it sticks very well and when it dries overnight, the adhesion is excellent. I used it to seal around the windows on the inside of my pool. Note: it is very thick

Good performance without the 5200 difficulties

I like using it my only complaint is that they don't include a cap for the tube tp better preserve unused material.

Excellent 3M Product.

This product, like all 3M products is outstanding. I used it to reseal a Pilothouse to deck seam that had developed some leaks. The previous seal/caulk had dried out, shrunk, and cracked. I cut it out and refilled the joint with 4000. I cleaned the area with acetone, masked off beyond the seam and applied 4000 with a caulking gun. The sealant flowed smoothly and filled the joint completely, easily resealing the leaky joint. This product is waterproof so cleanup is messy if you get it where you don’t want it. It does not smooth with a wet, gloved finger, merely smears. Apply enough to fill your joint and no more. Small overages will be “cleaned” up when you remove the masking. I applied the 4000 to a joint almost forty feet in length overall and the cure time is not so quick that I couldn’t easily pull the tape without pulling the caulk. It made an attractive seam and fixed the leak. Unlike 5200, 4000 doesn’t dry/cure so hard that it has to be ground out to remove it, but can be cut out with a knife at some future point if necessary.

Always keep a tube around if you have a boat.

This works great in any marine applications where you need a tight waterproof seal. We used this to seal new portlights that were being put into a friends sailboat and it worked like a charm. I always have a tube of this around. The price on Amazon was much better that the big marine retailer also.

Good product, but not easy to remove if required

I VERY MUCH DO like this product, but once dried it is resistant to easy removal. I used it for general sealing & caulking on my boat & it does an EXCELLENT JOB! Great container & quality of product.

Kwik set sealant

I have used this stuff for years. Installed all new hatches on my Lagoon 380 catamaran, solar vents on 27 Catalina and scubbers on the houseboat. You have to work fast , and don't forget to tape off around what you're sealing. Pull the tape before it sets up or it won't come off. Clean up with acetone. Do Not Use Alcohol to clean area to be sealed . This will keep the sealant from setting up properly ( per instructions on tube and website). It takes about 20 minutes to set or tack so have your clean rags ready beforehand. Good luck and happy sealing.

Great sealant but it can be removed if necessary.

I like the Fast Cure 4000 better than the Fast Cure 5200 because the 4000 is more forgiving. You can remove it if needed whereas the 5200 pretty much is forever.

3M 4000 look no further there's nothing better

It is amazing durable and professional adhesive that has amazing strength. I like to let a very little ooze out around the fitting and let it remain for a finished appearance. It seems to dry hard and shiny yet it will squeeze a little if you try with pliers. Its what I use for all above water line work, and the 3M 5200 for below water line and structural work. If they used 3M 5200 to build roads with in Buffalo, we wouldn't be known as the pothole capital of the country. Maybe I'll contact 3M about this brainstorm idea ...

If this can't seal it, it can't be sealed

Moving to a new house, we unknowingly let a vinyl lined hot tub (Softub) sit in the summer air upside down for three months. BIG mistake. This resulted in several rips and tears (including one 2 feet by 6 inches!) in the inverted sagging of the long-water-dependant vinyl. We thought our hot tub was a goner. Tried numerous hot tub rip repair kits, and none of them worked well enough for this major repair job. The hot tub was aging and had served us well for nearly a decade, so we didn't want to purchase a complete replacement liner because of the price - either fix it or toss it. Vinyl patches provided were strong enough, but none of the vinyl patch kit adhesives were able to really withstand the stresses of a full 300 gallon water load on the stretchable vinyl. We made all repairs while tub was empty so as to obtain the best seal. In addition to vinyl-specific glues and patch kit adhesives, we tried vinyl contact cement, shower pan liner adhesive, and every single type of PVC/vinyl glue at the local home improvement store. Not even Loctite plastic bonder would hold once the hot tub was full and chlorine was added to the water. As a last resort, we decided to give this "below the waterline" "hull repair" "permanently flexible" sealant a try - and WOW! it sticks to everything. We gave it a good cure of several days (this was outdoors in winter, so took a bit longer). We used this to adhere the vinyl patches to the tub' vinyl liner, to each other, and to feather around the edges so as to prevent bathers from tearing up the sides or water working the sides loose from the jets. 2 months in to this repair, from which no other product/system/glue previously lasted longer than a week. Much impressed by the miracles of modern petroleum strength commercial chemical derivatives - nicely done 3M!

Awesome for anything external on a boat that gets sunlight

Excellent sealant/adhesive for use on the boat cockpit. This stuff is great, i use it mostly for screws and bedding items when i want more tack than Lifeseal. While there are many great UV options available these days, 3m 4000 seems to perform better than most from what I have seen. WIth this item you get more or less a UV stable version of 4200.

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