Leaking sewer pipe

Most probably it is because the ventilation pipe on the sink is not exhausting the methane gas properly, so the methane/rotten egg smell is coming out of the drain. Sometimes if vent pipes are not angled properly, the gas/smell will not rise properly. If there is no ventilation pipe hooked up to the sink, you will most probably smell it. Good luck.

If the ring that is attached to the floor and sewer pipe is broken you can get a new ring that fits over the old one ..depending on the type of floor if wood you just screw new plastic ring over the old one be sure to line the bolt slots at the 3 oclock and 9 oclock position so you can slide the bolt head under the new ring and lines up to keep the bowl holes in exact spot. when you put the new wax ring on be sure to get one that has a built in plastic flange that goes down inside the 4 inch sewer pipe before putting plastic wax seal on be sure new ring is snug i always use a course wood screw to screw to the floor if you have concrete you will have to place ring make mark for screw holes drill masonary bit then put insert into concrete then put ring on then coarse screw good luck this should solve the issue

If the cast iron pipe is a drain or sewer pipe , the tape may work. It depends on the size of the hole. If the hole is in a joint an epoxy patch will work, such as JB Weld. Clean off the pipe with a wire brush and remove any grime. I would plug the hole first with epoxy, and then put the tape over it.

For drain pipes (waste water) they're fine.

But for potable water (fresh water), the cast iron could rust, allowing the rust to get into the water.
Also, the iron could leech into the water.

To be sure a camera inspection will show if there is a broken pipe before you start taking up floors .

they are typically made out of cast iron, often with little bits of concrete infused in them

plastic or croc? earthen ware? whats the material?

Thank you for posting your question here on Fixya.com.

If it is a Hayward valve like your post suggests there will be a word cast into the black plastic area near all three ports you need to connect. One will say pump, another return and the last one waste.

Pipe the pump port to the pumps discharge. Pipe the return to a heater if one is present or back to the pool. Pipe the waste to an area where you can safely discharge water as you backwash the filter.

If this answer does not fix your problem, please comment with additional details prior to rating the answer. You may also contact me thru our website at www.arrowpools.net. Positive feedback is appreciated once your problem is solved!

John

You didn't state the size of the pipe or if it is PVC(plastic) or Cast iron. Two rubber couplings can be used to repair the joint. A 12" section, 6" on either side of the joint needs to be cut out. Cut a piece of schedule 40 drain/waste pipe same diameter as existing pipe to size(just under 12"). Take two rubber couplings (sized for your pipe) and place on each end of pipe joint, and tighten clamps.
This fix will work on cast iron pipe, but there may be another means of repairing the joint, so get back to me with more info about the pipe and joint.

Phil, I recommend a ratchet snap cutter as it will allow you to cut the pipe in a clean manner. These are available for rent at most major home improvement stores in the US. One can also rent one at a tool rental company. I rented mine for $35.00 the bulk of which was a deposit on the tool. Just a reminder when buying the coupling device ensure you ask for or get a 4 inch cast iron to 4 inch PVC coupling. A bit of vaseline will help you get the neoprene coupling to seat properly with the PVC if you encouter resistance. Good luck. If you need more assistance let me know.