How far to seat PVC pipe? Advice Appreciated

[IrishSwede]

Firstly let me thank anyone for taking the time out of their busy lives to help me, I really cannot say enough how much I appreciate it.

We were in the process of attaching our PVC drain (fused to our prefab shower base) to an ABS pipe to attach it to our ABS DWV.

The issue/concern is, after applying the primer and ABS-PVC Transition Cement, we applied the pipe into drain. While I was pushing the pipe in my wife fell over.... by the time I could apply more pressure it was too late and I did not want to risk breaking the weld.

So 3 questions

1. What is the minimum that it must be seated? It is somewhere between 3/8 - 1/2. Unfortunately, if it is not sufficient, we would need a new shower base. I would if you (the brain trust) say I should. I put a cap on it and am currently testing for a leak, but would not want failure down the road....Oatey said if it doesn’t leak now we are ok, but that’s Oatey...I also stupidly added primer to the ABS side, but again Oatey said it would be a “now” problem.

2. Can I add a silicone sealant or epoxy between the top of the pipe and indent so water does not sit in it? What is better if so? Kwik Seal Ultra or JB Weld Plastic?

3. If the brain trust says it is ok to proceed, my next part is to attach the base to the coupler below. I intentionally left it 1/4 short from fully seating in the coupler below as I can only press it in (no 1/4 twist), is this ok? As the base has to be set on a bed of mortar, how long do I have after applying the cement to attach it?

Again thank you for any help or advice on the matter, it is greatly appreciated.

 

[Jadnashua]

Ideally, the pipe bottoms out of the socket it is installed in. The socket is slightly tapered, and generally, you can't bottom it out unless the solvents in the cement literally melt the plastic some. It reaches its best stability when properly installed. But, if it doesn't leak, the only thing is to ensure you provide some stability to the rest of the piping attached to keep stress off of that joint that isn't as strong as it should be.

I"m not a pro on this.

 

[Sponsor]

 

[IrishSwede]

Thank you for the feedback - left a cap on the pipe overnight, with no leak, so going ahead with the install. I measured the pipe and it sits about 5/8” in the drain, so not awful I suppose.

Any advice for setting the pipe on the coupler from above? Just cement the coupler and pipe and hurriedly press it on and stand on the drain for a few mins? It would be a huge hassle, but should I cut an access below to press up on the pipe? Or is downward pressure sufficient?

 

[IrishSwede]

...by huge hassle I mean the contractor said we would always see the hole no matter how good the repair was. His advice was just set it on, but he stated over and over he’s not a plumber

 

[Jadnashua]

It depends on how well the pipe below is anchored and how long the arm is. When I did this at my mother's house that has plastered walls and ceilings, I was able to put a block of wood beneath the p-trap so it was stable, then pushed the drain in to make the seal. If the pipe below is floppy or the arm is long, it will bend rather than letting you seat the drain onto the riser, potentially giving you a bad joint.

You might be able to wrap some strong tape around it below to help hold it while seating the drain, or maybe some string.

 

[IrishSwede]

Thankfully the trap is drilled through the floor joist so it has ‘no give’ in it at all. I may just cut open the roof to make sure it seats as far as possible....otherwise I guess I will always wonder “what if...”