Gravity Fill Sealant

[Midwest Expectations]

We were out with our new rig this weekend and had a thunderstorm come through. We had some wind, and some heavy rain, fortunately no hail. It rained most of the night.


We noticed a small amount of water leaking at the floor line in the bedroom of our 2970RL. Like maybe a couple of teaspoons; so not a lot at all. This was on the floor, below the egress window--along the floor trim, forward, towards the pass through storage area. The interior of the wall, below the window, felt dry and there's no visible indication that that water came through the window area.

I noticed the next morning that they weren't exactly generous with the sealant around the gravity freshwater fill, especially on the lower half of the fill connection. My suspicion is that the rain was coming in there. The connection is near where the water was observed and just above the floor line.

To fix, my plan is to remove the screws, pull out the freshwater connection enough to clean and re-seal the whole thing with silicone. Just thought I'd check the forum first to see if there's anyone that has had a similar issue, to maybe match assessments and confirm my approach to resolving it is similar as well. I'm not sure how much wiggle room there is in that connection as to how far I can pull it out (obviously, I don't need much).

Thanks in advance...

[Country Campers]

You may try some butyl putty for a good seal but not as permanent as the silicone. There may be a gasket behind or nothing. Some of my outside items seem to not have any sealant visible and I am not sure if it is sealed or not.

Brian

[TucsonJim]

I agree with Brian. I'd reseal it with butyl putty. If you're looking for it on Amazon, the correct search term is "butyl seal tape". Make a gasket with the material to fit the shape of the filler. If you have a seam in the tape, place it at the bottom.


Jim

[Midwest Expectations]

Okay, channeling my inner newbie, but I'm curious why the butyl putty is preferred over silicone? GD [at least attempted to] seal with silicone. Not discounting your suggestion, just wanting to understand.

[TucsonJim]

100% silicone caulk does not adhere well to fiberglass. I wish they'd use another product in lieu of silicone caulk around items such as windows. Also, silicone will appear to be sealed, but if it lifts from the fiberglass, it will be hard to see. One way to check the seal is to try and slide a razor blade between the fiberglass and the silicone. If it meets resistance, it's probably okay.

Butyl seal remains flexible and provides a good seal against materials such as fiberglass, metal, plastic, etc. It is a little messy and some of it will squeeze out when you tighten the screws. But it's easy to trim off the excess with a plastic putty knife.

Jim

[Midwest Expectations]

Well that makes sense.

I was looking at the parts lookup tool, and there may be a 1/4" gasket behind it, too.

https://granddesignrv.com/owner-supp...s/detail/33497

[Guest]

Midwest Expectations The gravity fill vent is not connected (at least on mine) and has a blob of putty pushed into the vent from the inside of the rig under the cabinets. This can be seen at the 2 o clock position in the pic. Make sure the vent is capped if its not connected. Otherwise, re-sealing the gravity fill where it contacts the rig may be necessary. There is a release agent that is used on gelcoat fiberglass which can affect how well silicone seals to the surface. A cleaner for paint prep can be purchased at any auto paint supply store which will clean the surface so the silicone will bond well. Also only use GE 100% silicone as there are many cheap brands that simply do not work. Butyl will work also but plumbers putty will dry out over time and leak.

Jim