Silicone suggestions needed.

[qlake]

I need to replace the silicone that fills the gap between the center console and the floor. The original silicone has some black mold that appears to be growing inside it. I see 3M sells marine grade silicone as a sealant, in 4000UV and 5200, both 4000UV and 5200 are available in fast cure. Anyone ever replace this silicone before?

Thanks

[gnrphil]

from what I've read most people use the 5200

[yolo]

All the 3M stuff is great, I use them all, all over the boat. I use the lower numbers above the water line on anything that i may need to get out later down the road, which one i use will vary based on how soon/often i may need to take something off. Any 3M under 5200 is more of the silicone your thinking of and you'll be able to pull it off if you ever need to down the road.

I use the 5200 mostly below the waterline because its a permanent glue. For what your looking to do i would recommend one of the lower numbers in case you need to pull it out in the future because it got too dirty and you want to change.

Hope this helps.

[freezerfiller]

I use 4200 silicone above the waterline. If you ever need to get back in there (and you will) 5200 is a bear to deal with. 3M has as good of a mildew package as I've seen. 5200 is a polyurethane which means it will discolor faster to UV, and is recommended for below the waterline applications.

[Juan]

I replaced the sealant around my console a few years ago for the same reason and some of it had worked loose... I use Attwood 7200 Quick Cure Polyurethane Sealant on just about everything in the boat and some things that aren't. It comes in a tube that makes it easy to apply and I can get it at WalMart. It's just as good as 3M 5200 (actually better imo) and it hasn't worked loose or discolored since I did it.
After it cures, just like 3M 5200, it will come off with Acetone and a LOT of elbow grease if you have to remove it.

[T-Topless]

4200 and 5200 are not silicone. They are Polyurethane and far superior to silicone.

I have not found that 5200 (I don't use 4200) will discolor in the sun. It is very resistant to UV and I have 5200 siting in the sun for years that is still pure white.

I see no use for silicone sealant on a boat period . It doesn't stick well, and penetrates the surface so nothing else will ever stick to that surface again (and no solvent will remove it).

I wouldn't cheap out n d get anything with the Atwood name on it either .. cheap quality name. If you're going to do it, use good materials. 3M is the best.

[yolo]

I think "silicone" is like the word "Kleenex"

When someone has to wipe their nose they will ask for or use a "Kleenex" which is a brand not the actual tissue. A good example would be the first time i walked into the marine store and asked for silicone suggestions, they brought me right to the 3m section, so were all talking about a few different things here that give the same solution.

There are definitely good uses for both the permanent permanent sealants and the non permanent silicone/sealants. A good example of where i use the 4200 would be my dash. I have to keep the option of taking that dash off so i can get to the electronics wiring, the electronics mounts and the amp that i have installed back there. The dash sets into a cutout on the console and then secured by screws around the border, i posted a picture below. The reason i have to seal this gap is when the top of the console gets water it will run down to the edge where the dash is, fall into the gap and drip on the electrics and the wiring behind. If i used 5200 on there then i would literally have to pry it off and fix the fiberglass so I use the 4200 and it comes off easily.

I used the UV4000 in the gaps that qlake questioned originally. Reason for this is they are VERY visible and what everyone has to understand is that once 5200 hits the fiberglass, even before it dries, its a chore to get off and impossible to mold and shape to what you want it to look like, very little room for error. 4200 is much better, but still not as easy to shape and play with as the 4000.

qlake- my best suggestion to you given all the info you got here, buy a few different (they sell very small tubes) two pieces of wood together and about as far apart as the gap in the boat and test to see which one you like best.

Also, here is a guide for the 3M products that will give you some more insight: multimedia.3m.com/mws/media/238690O/bonding-and-sealing-applic-prof.pdf?fn=Bonding%20and%20Sealing.pdf