Black tank sewer connection leaking

[bdbetthauser]

Hello everyone, new member here (although I've been lurking for a couple months since we started living full-time in our RV). I have been dealing with a black tank leak since Christmas, I'll try to describe my problem so that maybe some of you can offer me some advice.

I first noticed the leak AFTER dumping the tank when it was nearly full (currently not at a full hook-up site, using the poop tote to dump) when the smell was unbearable and we couldn't locate an origin. I cut into the coroplast and discovered a large collection of black water (the odor and color left no doubt). The leak is originating from where the black tank connects to the sewer pipe (before the release gate, secured with a pipe clamp). Initially, the pipe clamp was loose and tightening it resolved the problem. Since then we had to move sites, which was only a short distance of <50 yards, and did not have any issues until last night when the tank was nearly full again. It wasn't full/overflowing but I had planned on dumping it based on our normal use.

And my favorite leak is back. Dumping the tank and tightening the pipe clamp temporarily fixed the leak but while investigating the reoccurrence I discovered some new information. The black tank appears to have slid forwards (or towards the bow/aft/stern, I don't know because I'm in the Army not the Navy); this guess is based off the gap between the tank outlet rim and a ridge in the white sealant around the sewer pipe. I also noticed that I can press up on the black tank and raise it off the parallel support beams. I tried to push it back towards the sewer pipe and was able to maybe get 1/4" movement before obtaining a solid seal with the pipe clamp again.

My assumption now is that the leak is caused by:
- the black tank moving during travel and sliding away from the sewer pipe
- when the black tank gets heavy and bows down, it causes the connection to bend (I thinking the single cross support beam beneath it doesn't provide enough support)

So my questions:
1. Has anyone experienced this before?
2. Is the black tank actually bolted/secured to anything other than the toilet pipe and sewer drain pipe?
3. Does anyone have any schematics that might help me come up with a plan to prevent it from happening again?

I'd appreciate any tips or advice, thanks! I don't have any photos right now because I was dealing with this in the rain after dark but I can try to add some tonight if needed.

 

[Second Chance]

Forward = bow; aft = stern.

Is your rig still under warranty? If so, I would have GD intervene. It sounds like you have assessed information correctly and the black tank needs to be properly positioned, fastened securely, and some extra support added. This situation is not terribly common but others have experienced similar.

Rob

 

[bdbetthauser]

Is your rig still under warranty? If so, I would have GD intervene. It sounds like you have assessed information correctly and the black tank needs to be properly positioned, fastened securely, and some extra support added. This situation is not terribly common but others have experienced similar.

I have contacted them and I need to send them some pictures later today before they can provide my with any more information. From what I understand the 1 year warranty has expired, so that option is off the table.

 

[Second Chance]

I have contacted them and I need to send them some pictures later today before they can provide my with any more information. From what I understand the 1 year warranty has expired, so that option is off the table.

GD is really good about working with you on significant stuff even if the warranty is expired. Perhaps they can cover it under the 3-year structural warranty if support is deemed to be the issue.

Rob

 

[Soundsailor]

Hey [MENTION=52166]bdbetthauser[/MENTION], just wanted to welcome you to the forum. Sounds like you've already gotten some good advice from [MENTION=870]Second Chance[/MENTION]. Sure hope you're able to get your issue straightened out, it sounds unpleasant. Keep after GD customer support, I've had to be persistent when working with them, usually they've come through in the end.

 

[geotex1]

[MENTION=52166]bdbetthauser[/MENTION], the problem is not unusual by any means in the RV industry, and that factory does not always do a great job of supporting tanks... You can do a quick Google search and find years, decades even, of report of tanks falling out! Good news is your repair shouldn't be too bad. Like a restraining strap or tube steel bracket missing. You will want to pull out the affect insulation and replace as well as disinfect the coroplast when it's dropped for the repair in order to rid the coach of the odor or it will linger. Good chance the GD will send you any part found missing, but unlikely much more than that. It can be a DIY repair as it would be nothing too technical, just labor intensive but still doable in an afternoon.

 

[bdbetthauser]

Thanks [MENTION=26275]geotex1[/MENTION], at this point the repair isn't the most daunting part once I have the pieces I need. Unfortunately, while diagnosing the problem I have cut out a lot of Coroplast (didn't realize i could just disinfect it, but I may replace it with a window to monitor the leaking area).

[MENTION=870]Second Chance[/MENTION] [MENTION=43166]Soundsailor[/MENTION] I called GD and got the design schematics, interestingly enough my front grey and black tank are in switched positions. GD also said they don't use any sealant or pipe clamps on the black tank connections, so that someone else must have worked on the leak and completely swapped tank locations which seems like a lot of extra work for no reason (there is no other evidence of repair that I have found up to this point). The previous owner had both the 1-year factory warranty and a third-party extended warranty and neither warranty service claims any service was ever done (but why would anyone do work outside of their warranty when they can get it done for free).

At this point I am inclined to believe the previous owner based on the friendship we have developed, but I don't understand what GD would have to gain by lying to me because it's outside of their warranty anyway.

Here are some pictures:




I'm sure I can secure the tank itself, I just really want to know what sealant/clamp/other method I should use on the connection to prevent further leaking.

 

[trailrydr]

Thanks [MENTION=26275]geotex1[/MENTION], at this point the repair isn't the most daunting part once I have the pieces I need. Unfortunately, while diagnosing the problem I have cut out a lot of Coroplast (didn't realize i could just disinfect it, but I may replace it with a window to monitor the leaking area).

[MENTION=870]Second Chance[/MENTION] [MENTION=43166]Soundsailor[/MENTION] I called GD and got the design schematics, interestingly enough my front grey and black tank are in switched positions. GD also said they don't use any sealant or pipe clamps on the black tank connections, so that someone else must have worked on the leak and completely swapped tank locations which seems like a lot of extra work for no reason (there is no other evidence of repair that I have found up to this point). The previous owner had both the 1-year factory warranty and a third-party extended warranty and neither warranty service claims any service was ever done (but why would anyone do work outside of their warranty when they can get it done for free).

At this point I am inclined to believe the previous owner based on the friendship we have developed, but I don't understand what GD would have to gain by lying to me because it's outside of their warranty anyway.

Here are some pictures:
View attachment 44857
View attachment 44858
View attachment 44859

I'm sure I can secure the tank itself, I just really want to know what sealant/clamp/other method I should use on the connection to prevent further leaking.

Another consideration could be that the original selling dealership did the "fix" after noticing a leak. And, not sure about your 395, but on our 295RL the black tank sits under the toilet - assuming that it makes it easier for a fairly easy, straight and less compromised connection.

 

[bdbetthauser]

My black tank is on the driver side, the grey tank is directly under the toilet (opposite of the images GD sent me). I suppose it could have been done by the dealership but the previous owner pre-ordered and picked it up at delivery.

 

[geotex1]

That black tank connection did not leave GD that way. Also, make certain you're reading the diagram from the correct vantage. The excerpts they sometimes send will confuse whether you are looking up from ground, down from floor, inside out, or outside in, and if an assembly diagram realize they have them frames initially inverted. Nonetheless, I think you're going to be unsuccessful getting that sealed up short of taking the entire tank out and carefully grinding off that butchered sealant mess! As others mentioned, if you believe the former owner, it's entirely possible this was a dealer pre-sale fix. RV world is a little different in what defines factory new... I've been at the factory when coaches arrive back for partial rebuilds after delivery disasters and the dealer sells them as new. True, there is also an extent this can happen in the automotive industry as well, but the magnitude different.