About a year ago I had a cast iron drain pipe crack down its length. Plumber came out and replaced the cracked portion with pvc. Looks like he joined the two pvc to cast iron with some sort of rubber connector w/ bands at each end.

Noticed some bubbling in my drywall last week, cut it open and there is water leaking out of the top of the rubber connector. Most of the water goes down the drain properly, but it slowly comes out the top. I tried to just tighten the bands, but still has some slight leaking at the top.

Of course the plumber I used is no longer in business, so I'm looking for some do it yourself advice.

Is this just a wrong size connector problem? Do I need some sort of sealant between the connector and the pipes?

Any help is appreciated.

Thanks

It sounds like the other part of the cast is cracked if it is leaking out of the top of the coupling.

Is the rubber coupling a fernco with 2 gear clamps or is it a rubber sleeve inside a stainless steel band with gear 2 clamps?

Is this drain horizontal or vertical?

A picture is worth a thousand words if you could post one. Hope this helps , Good luck

This is a vertical drain pipe. The pvc is on top of cast iron. I'm not sure if it's a fernco or not. It looks like a rubber sleeve with a gear clamp on the top and bottom of the sleeve. Its leaking at the top of the sleeve where it connects to the pvc.

Thanks

That's a fernco and they do not hold up as well as the stainless steel banded clamps.

Speedball has posted several picts on the different ones if you can search the site.

It should stop leaking if you tightened the clamps. Is there any blockage in the pipe to make the vertical line hold water?

There may be some blockage at the point of pvc to cast inside the rubber coupling.

Let us know how it works out.

... also, Cast Iron and PVC have slightly different O.D. They actually make No-Hub coupling that is made specifically for connecting CI to PVC. Some plumbers use one type of coupling for all connection, regardless of type of pipe. In this situation, this coupling doesn't fit the way it should and may produce a leak.

Hi Bcampbell99:

The plumber should have use a SHIELDED TRANSITION CLAMP... see picture. This transition clamp is specifically made to transition between cast iron and PVC pipe.

The issue here, however, is really whether you have service weight cast iron (SV) or extra heavy cast iron (XH). To determine this look at the fittings and pipe and look for SV or XH.

Then you would order the shielded clamps from a plumbing supply store to match the cast iron type, for example, a 4" XH cast iron x 4" PVC shielded clamp.

They also make transition PVC fitting for standard weight cast iron pipe. Here, you purchase a NO-HUB x PVC adapter (see image#2) and then install a regular no-hub clamp to join together.

Finally, if you plan on working on this cast iron VERTICAL stack yourself, you need to know that there is a serious amount of weight on that stack and it will need to be supported properly using riser clamps before you can cut into it... see other images.

Let us know if you need more info...

MARK