Help with identifying sealant used under coach

[oneydee]

Hi group,

We have a 32 foot '94 Adventurer and I need help with identifying what sort of sealant to use to replace worn/missing factory stuff used to seal plumbing under the coach. Specifically, I am finding very worn, black (maybe just dirty?) rubbery feeling caulking/sealant missing or falling off from the plastic, fresh water and internal plumbing drain pipes. The sealant frankly looks like a doughnut as it was slipped over or applied around the drain pipe as it exits the floor of the coach.

Does Winnebago use anything special or would applying just any silicone or caulking do the job?

[Francesca]

Hi!

I'm guessing that you're looking at good ol' butyl tape (or putty).
Butyl Putty Tape, Non-Hardening, Increases in Adhesion w/Age After Application
It's been used for years in that kind of application, and as far as I know it can't be improved on!
It's far superior to silicone for the purpose. It stays pliable almost forever, and though it starts life grey, it'll "blacken" with dirt etc. over time.

You can buy it at any RV parts place and at many hardware stores.

Hope this helps!

Francesca

[oneydee]

Thanks Francesca...I suppose that could be the sealant used. I'll let you and the rest of the forum be the judge. Here is a pic of one of the "doughnuts" I easily peeled away from one of the drain pipes. Is this butyl tape?:

[Francesca]

Ohhhhhh Yeah.

That's butyl tape, all right!

Francesca

[hdmoxness]

Francesca, how does one apply the butyl tape where a pipe, tube, or wires pass through a hole in a surface with a rubber grommet covering the edges? Just wad it up and stuff pieces in until the gaps are filled? Or do you lay it on flat and expect it to mold itself to fit and seal?

I recently puzzled over filling some gaps like this and ended up using a latex caulk (DAP Dynaflex 230), which dispenses and fills nicely and claims to remain “permanently” flexible. Once cured, it’s supposed to be good from -30°F to 180°F. Anyone out there have some expert advice on caulks? Seems there are too many choices out there (like everything else, these days), and the home RV mechanic should have need for only three or four well-defined products (butyl tape being one). What are they?

[Francesca]

Hi, Dean and Diane

I usually just wrap the tape around the pipe/wire and push it into any gaps with a putty knife or other right-size tool. It's malleable like clay, which is one of the things that makes it so useful, in my opinion.
Latex caulks get pretty mixed reviews here- I've never used them for this kind of purpose so can't tell you anything about their life/efficacy etc.
Hopefully others will chime in who have experience in that department...

Good luck!

Francesca