Cracked Black Water Drain Pipe

[RJV]

Noticed the strangest thing this spring when I went to bring the trailer home from the place I store it overwinter. Some of the insulation on the underside of the trailer, about 2 feet away from the drain valve, had fallen away.

After getting it home, and cleaning up the area so I could re-foam the pipe, I noticed i had about a 6" crack in the ABS pipe.

Replacing the section of pipe is the obvious answer but it's a devilish location. I've been made aware of a product called JB Weld Waterweld. Does any one have any experience with it? Are there any other solutions the Escape brain trust might have?

[RJV]

A couple of pictures for reference:

[occer]

Repairing ABS pipe is very easy. You can repair the pipe without removing it.

I’ve fixed more then one. The way I do it.

Drill a small hole at each end of the creak, “this stops the creak from traveling”
Take a dremel tool and “vee” out the creak very slightly.
Use regular ABS glue and dab glue into the grove. Let dry for an hour or two.
I apply a second coat of glue and press a fiberglass or nylon mate into the glue, have the fabric overlap the creak an inch or so past the ends and above and below the groves creak.
Apply a finial coat of glue over the patch beyond the fabric a little bit.

That will be the strongest part of the pipe. That creak is probably form a compression force on the bottom. Check the other side to make sure it’s not creak on both sides.

[Ron in BC]

I agree, ABS is very repairable.

But I'm pretty surprised by the damage. I'd like to know what caused it. In a way it's a good thing that the insulation fell away. Otherwise the pipe might have oozed the contents into the foam and then started to smell.

Ron

[RJV]

Thanks for the information. I'm still curious if the JB weld might be the putty to make the repair.

As to why it happened? That's the million dollar question. I wonder if the break didn't happen some time ago and moisture had seeped into the foam. This winter we had a couple of heinously cold spells dipping well into the minus 20C's. I have to wonder if the expansion of the interior moisture didn't just fracture the foam into pieces. I just can't imagine anything else happening. If there was residual water in the pipe after having drained the system for the winter, I have a hard time imagining the pipe would "expand" enough to force the insulation to fracture away.

I doubt we'll ever get the answer. I does however make me wonder if i have other cracks in the system.

[Ron in BC]

Originally Posted by RJV

Thanks for the information. I'm still curious if the JB weld might be the putty to make the repair.

I'm sure that JB weld would do the job. Folks use it for all sorts of repairs including some that require much more strength than this one.

Personally I'd use ABS glue. It's a solvent cement and literally melts the ABS.

Ron

[occer]

JB Weld will not be permanent. JB Weld is a great produce but not the best option in this case.

ABS glue is a solvent based glue, it melts the pipe and when the solvent evaporates the glue becomes part of the pipe.

[occer]

See if there is any evidence of the bottom being struck by something causing the foam to fracture and the pipe being compressed. Lateral creaks are usually cause from the pipe being compressed.

One of the characteristics of spray foam, the outside surface if not trimmed is water proof.
It will not stop water from seeping between the pipe and the foam.
The foam will absorb water if the surface it broken.
Another words the foam would not absorb moisture unless it was fractured and the outside surface disturbed.