Hello allMy Class B rig, a 99 Xplorer XLWT, has a leak in the black water tank, which is fiberglass, and resides INSIDE the vehicle, and is molded into the shower enclosure. Removal of this tank is pretty much impossible without tearing the whole rig apart.I can't see the leak, but the carpet inside is wet, and eventually, the moisture makes its way outside...that's how I discovered the leak. (Edit: Runs in the side of the tank are resin from initial manufacture.)Is there some sort of material that can go INSIDE the tank to seal it? I think I can manage to get the toilet off the tank to get in there and clean it well enough.Not fun.Ideas?Thanks,Gerard

Maybe one of those plumbing pipe reliner companies can blow in their flexible liner that hardens. Its kinda like a balloon. You may have cut off and redo the outlet or something like that.

If it is indeed fiberglass and you can reach inside well enough to locate/clean/prep the leak spot, a mat-and-resin fiberglass patch should do the trick. You can buy such kits at any auto supply store for about twenty bucks.Side note:Are you sure it's leaking from the inside? I ask because that water in the pic is so clean I wondered if it could be condensation...

How do you know it is the black tank leaking?

The more I review the picture it looks like the water droplets come from mid tank or above.

352 wrote:The more I review the picture it looks like the water droplets come from mid tank or above.The runs in the photo are fiberglass resin from initial manufacture.I know it's the black tank, because I turned off all the other water, then put a gallon of water through the toilet to the black tank. The carpet got wet, and within 30 minutes, water was dripping outside.I can feel wet carpet under the tank, but it's impossible to access from the exterior.Gerard

Leaking FIBERGLASS Black tank | Good Sam Community

17 Replies

Gene_Ginny
Explorer
Feb 12, 2014
torinoscj429 wrote:
... How does the toilet flange come off the shower pan and black tank? ...
I have never done it but I have heard several people say the toilet flange is threaded and screws into the tank.

PS- pictures are back. :C
DiskDoctr
Explorer
Feb 12, 2014
It's not aerosol, but you can use ordinary vegetable oil on the rubber seals, like Fernco. Crisco is also OK, but is messier and often reserved for outdoor assemblies (think new sewage pipe with the rubber donuts as seals). They sell a pipe lube for this kind of assembly, too.

When updating my FIL's home with 100' of new sewer line to connect to public lines, we bought pipe lube. When making unexpected repairs involving cutting pipe, we've grabbed Crisco to slide Fernco all the way on one pipe then slide back to cover the joint.

Veg oil is best for vertical existing couplers as gravity helps get it into the joint. A heat gun can be helpful, but only a little heat to help soften the fitting.

A small diameter blunt tool can often be worked in between the coupler and the pipe, breaking the 'stickiness' between them (rubber tends to stick after a while), which also is a too way to get the veg oil started.

Hope this helps.
torinoscj429
Explorer
Feb 11, 2014
Gene&Ginny wrote:
Pictures don't show. The host site for the pictures above gives this message: NOTICE: This domain name expired on 2/10/2014 and is pending renewal or deletion.

Those GoDaddy people are prompt! Pics should be back up soon.

Gerard
Gene_Ginny
Explorer
Feb 11, 2014
Pictures don't show. The host site for the pictures above gives this message: NOTICE: This domain name expired on 2/10/2014 and is pending renewal or deletion.
torinoscj429
Explorer
Feb 10, 2014
Bob Landry wrote:
I know it is really a chore to pull the tank, but that may be the only way to determine where the leak is actually occurring. If it's on the bottom, it has to come out anyway. While you may have enough of an opening to get a camera or even an inspection mirror down in the tank, it unlikely you would have enough room to reach in and do an acceptable repair. Fiberglass repair is easy, but it requires some sanding around the bad spot, cleaning with acetone and laying in fiberglass cloth saturated with resin, and you need to see what you are doing as well.

UPDATE! After further disassembly, I can see how to get the tank out. I'll have to drop the grey tank to remove the long pipe, and get the toilet flange out of there, and then slide the tank out of this opening. Do-able.

How does the toilet flange come off the shower pan and black tank? I don't want to break this obviously hand-laid fiberglass tank.

What kind of spray lube is safe to use on these rubber couplers?

Gerard
mayo30
Explorer
Feb 10, 2014
Like I suggested find the leak first,if it is in fact not plumbing and the lower or bottom part of the tank,cut out the side that you can get at,go in fix the leak.Fiberglass the hole shut using the cut out piece as filler,then eterna bond over the patch.As others have said fiber glass repair is not expensive or hard.I am betting on a plumbing leak.
Bob_Landry
Explorer
Feb 10, 2014
I know it is really a chore to pull the tank, but that may be the only way to determine where the leak is actually occurring. If it's on the bottom, it has to come out anyway. While you may have enough of an opening to get a camera or even an inspection mirror down in the tank, it unlikely you would have enough room to reach in and do an acceptable repair. Fiberglass repair is easy, but it requires some sanding around the bad spot, cleaning with acetone and laying in fiberglass cloth saturated with resin, and you need to see what you are doing as well.
mayo30
Explorer
Feb 10, 2014
Get or rent a fiber optic camera and start checking inside and under before you plan any repair.
DiskDoctr
Explorer
Feb 09, 2014
Just a shot in the dark here, but is it possible it is the fitting of the drain pipe that attaches to the bottom of the tank?

Your 1 gallon test would seem to point towards a bottom of tank leak.

You could try a UV die pack like they use in air conditioning, coolant, and other systems. It will leave a distinct "stain" where it is leaking that can only be seen with UV light. You'd want to watch and catch it soon after it started leaking so it isn't spread around (seems to be the trouble you are having locating the leak using just water).
torinoscj429
Explorer
Feb 09, 2014
usmohls2@yahoo.com wrote:
How old is your rig? Under warranty?

99 Xplorer...company is out of business...

:-(

Gerard