Fixing a broken drain elbow?

[Maineiacs]

My gray water drain pipe has broken right in the middle of the 90 that I assume is glued to the tank itself. I'm used to working with PVC but I'm not sure how to best fix a broken elbow. Any suggestions from anyone unfortunate enough to have shared this experience?

[chuckster57]

The ABS 90 elbow probably has a short length of ABS that actually goes into the tank, and is held on by the hose clamps and sealant.

Cut the pipe after the elbow leaving enough for a union. Then just build the new piece, glue it in place. We use Dicor as a seal at the tank.

[Maineiacs]

Originally Posted by chuckster57

The ABS 90 elbow probably has a short length of ABS that actually goes into the tank, and is held on by the hose clamps and sealant.

Just to be sure I understand, are you saying that the ABS elbow and an ABS stub are attached to the tank only by hose clamps? Never having seen a naked tank I assumed everything was glued together.

[chuckster57]

Yup!!! I’ve seen a single clamp and double clamps.

[Maineiacs]

Cut through the coroplast today to see what's what. I have two gray tanks that use a Y fitting to go into the blade valve fitting. The bottom half of the fitting is where the 90 degree elbow was glued and that's what broke. Between a local RV store and Home Depot I found all the parts necessary. Some are PVC and some are ABS. Everything is glued together, tomorrow I'll bolt the blade fitting back together.


Now, what's the best way to seal up the coroplast?

[chuckster57]

All waste drain pipes should be black (ABS). Scrim tape is best for taping the cut seams.

[JRTJH]

Originally Posted by Maineiacs

...
Now, what's the best way to seal up the coroplast?

There is a "special glue" to weld ABS and PVC tubing together. The typical stuff on the shelf at HD or Lowe's is for one or the other... I'd check out a "real hardware store" and ask for the correct glue since this repair is inside the coroplast... The other stuff would probably work on a house where there's no movement, but in an RV where you've got flexing and vibrations, I'd highly recommend using the correct adhesive...

As for closing the coroplast. I'd use a nail or a scribe to punch holes along the cut and thread zip ties through the holes to secure the "flap to the rest".. Then, use HD Gorilla tape or SCRIM tape after thoroughly cleaning the coroplast so the tape will stick properly. Then, even if the tape fails, the cuts are secured by the zip ties.....

ADDED: Oatley Green is the correct glue for ABS to PVC... https://www.lowes.com/pd/Oatey-4-fl-...E&gclsrc=aw.ds