Brain picking time, what is the adhesive used in tank fittings.

[ThePowells]

I remember reading about repairing this connection, but I can't find a keyword that helps narrow the search. Over the weekend I replaced the gray valve, but when I dropped the coroplast I found wet insulation localized to the gray tank. After replacing the valve, I washed clothes and took a shower and let it sit overnight. Sunday I found the leak to be coming from the the white sealant. What is it and how to repair it?
This doesn't show the actual leak location, but it is the white sealant.

[ThePowells]

Okay, now I have found the real pic of the culprit. It appears to coming out at the bottom as best I can tell. What is the white sealant? As soon as I get my tank bypass plumbing into place I'm going to attack this while I have the bottom down, hopefully over Wednesday and Thursday between everything else (mainly appointments).

This exercise has cleared up a few things. First that there is not nearly the lip that I had expected to see at the opening, and the low points of the tank bottom is what is stopping the tanks from draining cleanly. I did take Rob's advice and cut the waste pipe just down from the coupling and added the slip connector. I put it to where when it is slid up against the coupling that the cut is directly in the middle of the connector.
If I have to pull this valve again, I will be able to do it from on top.

[ThePowells]

I found the thread I mentioned earlier... https://gdrvowners.com/forum/operati...at-tank-outlet

My search engine was going back thru Cate&Rob photos...

Do we have a name for the putty?

[Cate&Rob]

I found the thread I mentioned earlier... https://gdrvowners.com/forum/operati...at-tank-outlet

My search engine was going back thru Cate&Rob photos...

Do we have a name for the putty?

Hi Jerry,

Per the discussion that you linked, we discovered that early build products had the valve flange glued to the tank with a hard yellow solvent glue. Later products changed to a softer putty sealer and a band clamp. Per that discussion, Grand Design was not much help in identifying the type of sealer used. The good news is that with the later assembly method, the flange can be removed. The bad news is that there are reports of leaks that never happened with the earlier attachment method.

Rob

[Canyonlight]

Hi Jerry,

Per the discussion that you linked, we discovered that early build products had the valve flange glued to the tank with a hard yellow solvent glue. Later products changed to a softer putty sealer and a band clamp. Per that discussion, Grand Design was not much help in identifying the type of sealer used. The good news is that with the later assembly method, the flange can be removed. The bad news is that there are reports of leaks that never happened with the earlier attachment method.

Rob

Rob - thanks, for this. I saw a poster with a 2017 337 having a leaking BR grey tank. His pictures shared the clamp and putty and I was wondering about this as I knew ours were glued. You da man !

Jerry - I have not seen anyone post what the putty is either. Kinda confused that GDRV would not share that. What is so proprietary about pipe putty, I wonder.

Dan

[Yoda]

When I had the belly open I took a look at the putty - it appeared to be the same butyl stuff GD uses elsewhere. It was sticker than the plumbers putty I have used on the house in the past

[Cate&Rob]

If I were trying to repair the "putty and band clamp" configuration, I would be inclined to get the joint completely clean (as shown in the linked thread) and then use 3M 5200. This is a marine sealant designed for use on fittings below the waterline. When applied, you have working time to get things aligned as you want. The bad news (or maybe the good news?) is that once this sealant sets up, it sticks to anything and will not leak . . . but, that joint is never coming apart again. (I have seen fibreglass boat hulls come apart before the 5200 let go.)

Rob

[TucsonJim]

ThePowells I was able to make contact with the factory and obtain information on the sealant. Here are photos of the sealant and fittings that are ready for installation after the sealant is applied.





Jim

[Canyonlight]

Thanks, Jim ! TucsonJim for getting the scoop on and sharing the information on the "mystery" sealant.

Dan

[ThePowells]

TucsonJim THANK YOU!! Now I can hunt this down and get ready to do this when I drop the coroplast to finish my tank bypass project so it should have way more than 7 days to cure.

I've ordered two from Amazon.

[Cate&Rob]

I would look at this differently. The value in knowing exactly what sealant was used originally (and has been reported by more than one owner to have leaked) would allow me to purposely use something better.

Rob

[Canyonlight]

I would look at this differently. The value in knowing exactly what sealant was used originally (and has been reported by more than one owner to have leaked) would allow me to purposely use something better.

Rob

Agree, Rob. I would be interested to learn why GDRV changed from glued (not going to leak when done properly) to a "soft" sealant and a clamp.....will the clamp actually compress the tank outlet ? Tanks can and do move during travel and I suspect even during cycles of empty to full conditions. Yes, it may make it easier to change out a cable gate valve but the downsides of pipe connections that can (and are) moving resulting in leaks is already and seems to be a longer term looming challenge.

Dan

[ThePowells]

Agree, Rob. I would be interested to learn why GDRV changed from glued (not going to leak when done properly) to a "soft" sealant and a clamp.....will the clamp actually compress the tank outlet ? Tanks can and do move during travel and I suspect even during cycles of empty to full conditions. Yes, it may make it easier to change out a cable gate valve but the downsides of pipe connections that can (and are) moving resulting in leaks is already and seems to be a longer term looming challenge.

Dan

Both of y'all raise great points to ponder. In search of possibly a better option (the 3M 5200), but the sealant being stronger than it's base raises concerns. Knowing that another leak would result in the replacement of the tank concerns me and it wouldn't be covered by the warranty (only 2 more months left anyway). Thinking about the vibration and flexing raises other considerations about securing the system.

I completed the tank bypass today and was already thinking securing my long outflow line . I'm thinking that since it is resting on a bulkhead that either a zip tie or tarp strap will work, but given the weight on the springs I don't think wild gyrations will be a problem. More on that major mod when I get time to do pics.

[Mudchicken]

How did this turn out. I have a 2015 317RST, Haveing tank problems, trying to reinstall and trying to figure the best way. Previsouly had the Goop on all the Tank fittings. Looks weird. Thanks for what ever help you all can be, Eddie M, Apopka FL

[howson]

How did this turn out. I have a 2015 317RST, Haveing tank problems, trying to reinstall and trying to figure the best way. Previsouly had the Goop on all the Tank fittings. Looks weird. Thanks for what ever help you all can be, Eddie M, Apopka FL

Welcome to the forum. Got a chuckle when read your forum name. Please check out the welcome letter to new members when you get a chance.

https://gdrvowners.com/forum/main-fo...to-new-members

Jerry ( ThePowells )--I believe this new member directed his query at you.