The thing about lead and oakum joins is that the lead is used to secure the oakum. The lead does not make the joint. If you look into the bell end of the CI you will see a recess inside the lip. When you pour the joint with lead you then take inside and outside yarning irons and you basically set the lead int othe recess and against the pipe. once the oakum begins to get wet it will swell and that is actually what mass the joint. I like the Mission band brand of couplings. that said, if I am working to two fixed points with a single piece I will get a no-hub coupling that I can pull the clamp and outer support back, affix the rubber coupling to one end of the pipe and fold it back on itself. Position the pipe and roll the band back over the new pipe, whether CI, or PvC. Your dimension has to be spot on, but I've done a lot o them. Also, if you are going CI to PVC/ABS they make special claps for that.

When running PVC for pressure piping code allows us to thread schedule 80 pipe providing we do not exceed 50% of the pipe pressure rating however code does not allow schedule 80 PVC for DWV(Drain,Waste & Vent) applications therefore if it is a threaded joint we could see a PVC thread adapter. We can also rule out an oakum and lead joint because the hot lead would have melted the PVC. The current code approved method of connecting PVC to cast iron is by means of an external rubber sleeve held in place by metal pipe screw clamps (Mission bands or Fernco coupling) or a rubber donut coupling in the CI hub. There is another method that I, and many other plumbers, have successfully used in the past with the expressed consent of the local inspectors. Begin by inserting the PVC into the hub then tightly pack the hub 1/2 to 3/4 full of oakum and cap with Plumbers Epoxy in the same manner as lead was formerly used to cap the oakum. A variation of this method is to pack the joint with Oakum, then cap with "Plastic Lead" although I have never had much success with the plastic lead material. In Geller's case however they connected it, the PVC is only extended about 3" into the hub so I would suspect some variation of this method was used. PVC is relatively easy to cut with a hacksaw, so I would suggest using a "Stanley Mini Hacksaw" frame to hold a hacksaw blade from one end and cut the existing PVC lengthwise from the end of the pipe. (Hint-insert the hacksaw blade so that it cuts on the pull stroke to help prevent the blade from bending) I would make a cut at the top and bottom, then at the 3 o'clock and 9 o'clock positions. Once the cuts have been made you should be able to use a large flat tip screwdriver to pry the sections of the PVC out. When the PVC pipe has been removed you should be able to pry out the filler material and clean the hub then make up a new joint with a rubber CIxPVC donut gasket.

Thank you. I pulled everything out. It wasn't that difficult after heating the outside of the CI pipe for a minute. I'm glad I did because I saw a big boo-boo. When I first put the pipes together, I though that putting a little oakum at the front of the pipe might make a nice gasket in case the PVC didn't reach all the way back. I created a nice clog in the pipe before we had a chance to use the toilet! So, I'm sure that contributed to why the water was trying to get out around the pipe. So, I bought a donut from the plumbing supply store and used that. I soaped it up real good and put the donut into the cast iron first. I tried putting it on the PVC first, but that didn't work because since it was soaped up, it was just sliding up the pipe when I tried to push it into the CI. I had to use a 3LB hammer to get the PVC pipe into the donut. I'm not going to glue all the other pieces together until I'm sure that this isn't going to leak again, but I feel pretty confident that it's good now.

ThatÂs a good first posting, RH. I think you are a smart inquirer. Not that it matters. But, hereÂs a reply. Your query, "How long do these iron pipes last," is a great new question. The answer is, it depends. Aw Shucks. You see, if there are no extenuating circumstances, cast iron pipes are about as good as it gets. Of course, that is for old installations, such as yours. You can hardly beat PVC for new work. That said, if you have CI and it is properly installed, it will outlive you. I had a bad experience in a rental house. The idiots (sorry, they arenÂt that clever) installed CI piping when the sewers came thru after septic systems were the norm. It would have been just fine, except that the DIYers were not up to the task. They installed the new lines with a reverse slope. That is, instead of having a natural drainage slope of ¼" per foot, they installed the new pipes so that there was a small negative slope; but altogether it was a total fall. That is, the 4-inch pipes were fully adequate to take the flow, but the negative slope meant that there was a dip in the run that always was wetted with sewage. This failed, as luck would have it, years later when I became the owner. The CI pipe (No-Hub) which is a different recipe than the older version, was eaten-thru, so that is eventually formed a leak. The lower surfaces were rotted away and the leaks were evident as thin skin on the bottom-most outside diameter. This could easily occur, unseen, underground. CI pipe is a premium product. If you have it, it should last a "lifetime." Whatever that means. But I canÂt help thinking PVC is a superior product. I have also used ABS. It, too, is a great material for the purpose. It is much lighter in weight, but very durable. I would like to see it become the standard. Pinoke