What is the best glue for repairing slight smell at joint of large diameter pvc pipe.
It is a dry joint in the pipe, so I think the leak must be on the top of a horizontal portion of 90 degree juncture. So waste water must flow under the leak. Think I feel a slightly cold air at the juncture.

I have pvc primer and glue. But do not understand how this would work on an already sealed pipe. The pipe has been there for 10 years. How can I get this to fill the gap that I assume must be present. I do not want to damage the seal that is there. WOuld this risk damaging the seal that is there if I put it on the joint. Best procedure?

I also have Devcon Plastic Welder 2 part glue. That has more body that could fill the gap.
What type of glue is this. Would it work well for this?

Finally I have Silicone RTV. Does it stick well to PVC? Does it leave a residue that if I removed it would inhibit other glues from working, if I did not feel it worked well enough.

Once again there is no water leak, just a smell.