I need to seal my horizontal pvc pipe toilet drain that inserts into a cast iron hub. Please help! Soil seal is not working!

First, what is the size of Cast Iron Pipe and What is the size of the PVC pipe ?

I assume you have some kind of Y fitting in the cast iron pipe you plan to connect to. Get a Cast Iron to PVC Fernco coupling matching the size of both pipes to connect them together.

Hi Kyle...

I'm going to bet that you didn't pack some OAKUM into the hubbed joint before applying the soil seal... correct?

You need to install and pack the OAKUM into the hubbed joint so that you leave about an 1.5" of space to be filled by the soil seal compound. Oakum can be purchased in a bag at any of the major home improvement stores.

That should be all you need to do here. Otherwise, answer Milo's questions so we can direct you to the correct neoprene donut for your application... a bit harder to work with but makes a great seal!

MARK