Black tank pipe connection repair advice

plastrd · 08-08-2020, 11:11 PM

Started backing into my parent's driveway for a weekend visit. The slope of the road plus the apron on the driveway made the sewer connection at the very back corner of the coach bottom out. I eventually found an angle I could get up in the driveway without dragging but it looks like the damage was done.
Came out this morning to find a very tiny leak from the connector on the black tank. It was cocked a little bit from dragging and pushing it back together stopped the leak. There is a hose clamp and some black goop on the connector so I'm guessing the previous owner had a similar experience and patched it up.
Looking for some advice on a temporary and permanent fix for this situation. I'm afraid the weight of the black tank contents might push the connection apart and make a REAL situation and I won't be able to dump before we get home several hundred miles from now.
The connector is a black ABS union and angled bend. I'm not sure the hose clamp was actually doing anything since the parts are all solid (no rubber coupling in there). I used some wire to try and tie the pipe to the frame so it can't back off for now. How would that joint normally be secured, pipe solvent/adhesive? I can probably attempt that when I get home and can dump the tank so I can pull the connection apart. If there's a way to do it without separating the connection I would definitely favor that so I can stay away from the grossness in the tank.

javelin · 08-09-2020, 12:03 AM

Well the clamp is pretty standard I think since the black tank is poly which does not attached to ABS plumbing fittings without a proper adapter fitting in between. I think your adapter is probably cracked or the ABS pipe glued into the ABS side of the adapter. Hopefully the poly tank outlet is not damaged though. The clamp holds the poly side of the adapter in place in the black tank outlet fitting.....likely with some special solvent/glue/sealer. I am attaching a link showing the possible adapter used in your situation.....although I am not familiar with your particular coach. If you are not into this kind of repair, you could try to find a local RV Dealer who will do it with appropriate costs.

https://www.icondirect.com/holding-t...3-hub-fitting/

plastrd · 08-09-2020, 03:25 AM

Thanks for the description of how those fittings work and the link. I'm hoping since the larger hub side was able to slide back up the fitting being held to the tank with the hose clamp that it was just the solvent weld that broke loose. Still means I'll have to empty the tank to re-glue it but I have a better idea of what to expect.

javelin · 08-09-2020, 12:55 PM

I hope it works out well for your repairs. If you look down the page just under the adapter picture in the previous link I provided, it says to use their butyl rubber sealant around the ABS adapter piece that slides into the poly black tank outlet. So basically its just an ABS adapter coupling clamped and sealed into place. You probably should inspect the area after dumping the tank to identify what is actually damaged (if anything) and determine the best repair requirements. Maybe just re-sealing and re-seating the ABS adapter is all that is required. You don't want any "surprises" from the black tank on.....or down the road.

Bob Denman · 08-09-2020, 01:55 PM

I've used J.B.'s Weld Paste to fix everything from a leaky home sewer pipe; to a cracked crankcase on my kid's ATV.
It might be able to help...

GVP-The Boxcar Children · 08-10-2020, 06:53 AM

Quote:

Originally Posted by Bob Denman

I've used J.B.'s Weld Paste to fix everything from a leaky home sewer pipe; to a cracked crankcase on my kid's ATV.
It might be able to help...

Ditto Bob-I used JB Weld to seal an upper radiator hose sleeve decades ago-worked perfectly!
GVP

plastrd · 08-11-2020, 02:05 PM

Made it back home without incident though the gray tank had a similar leak and dripped a little along the way.

On the plus side I finally got to test my DIY macerator made from a home garbagr disposal and it worked great, at least THAT didn't leak! Pumped everything through 25ft of garden hose into a PVC pipe I put through the basement wall wyed into a sewer pipe coming from our upstairs plumbing.

With the tanks empty and flushed so they both dumped clear water I felt brave enough to get underneath and yank on the fittings to see what was bad. Turns out on both tanks it was just the connection from the collar on the tank to the ABS adapter like javelin linked above. The butyl sealant in the joint gave out leading to the small leaks. No cracks in the tanks or fittings so that was a huge relief.

Went to the hardware store and found some rubber polymer sealant for windows as close to the stuff linked to from the fitting link above and gooped it around the fitting as best I could. Pressed the fitting back in and tightened the hose clamp and so far so good. The black tank fitting needed a new hose clamp as it was rusted solid (and of course I bought the wrong size the first trip to the store). The gray one was fine though and just needed a good crank to tighten it up again.

Just glad I was going slow enough to stop right away when I heard the plumbing start dragging before it ripped the fittings completely out. A little annoying that there are welded steel drag bars at the back of the coach but they don't reach past that stupid crossover pipe. It seems like a lot of the newer floor plans put the bathroom and tanks on the curb side but they need a better way to route the plumbing across than way down under the frame rails.

Now to get it down to the tire shop to have the slow leak in the inner rear tire looked at. Annoying to have to put 10psi in it every trip, hopefully it's just corrosion or a leaky valve and not a puncture. This is turning into an expensive hobby!

Bob Denman · 08-11-2020, 03:18 PM

Glad to see that you made it home before...

https://www.thorforums.com/forums/at...1&d=1597159095

RichRob · 09-09-2020, 09:57 PM

Saw your advice on water leak and followed your advice. The leak was small and I applied the JB Weld. When I discovered the leak, I made an appointment with the nearest RV repair facility, and have the nearest appointment in two weeks. I will be using my RV next week, and this will be the first time since leak was fixed with JB Weld.
If there is no longer a leak, should I still make my appointment? I suspect that when they do repairs, it will not be a pipe replacement, but applying sealer (never faced this problem, so just guessing). What do you suggest?

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