We moved into a 50 year old home and replaced the old cast iron piping with Pex. We have been very happy with the change. The only remaining problem is that when we do laundry, the drain in the basement backs up. I am certain that it is also cast iron that has corroded over the years and no longer has enough draining capacity. We also notice and occasional “sewer” smells. We would like to avoid having to tear up the concrete and replace the piping at this time. Is there any temporary quick fix that will take care of the problem even temporarily?