Rich B
DIY Senior Member
I installed a new PVC 4x3 closet bend on to a cast iron pipe. I cut the hub off a sanitary bend on it's side as that is what was installed 50 years ago. The pipe curves very quickly behind where the hub was so there is very little area to work with. I dressed it up with a die grinder and cleaned the C.I. pipe well. The pipe is smaller on the OD than the 4" pvc so a Mission type clamp distorts some. I cut the metal band to seperate the two areas and allow the metal to form around the rubber. I had it on for hours and then noticed a slight leak after I flushed some water thru the pipe. I snugged the clamps up a little more and the leak appears to have stopped....but I don't trust it! Short of tearing out a lot of C.I. I have no other options for this. Is there and sealer that might be used between the C.I. and the rubber to seal it better. I tried Blue Block and it made more of a mess so I cleaned it all off and installed it dry.....I have access from above and below and there is no emergency here as the home is vacant right now......The horizontal run is 5 feet long and has 2 toilets and two sinks and tubs going into it. The biggest issue is it has improper pitch and waste water is collecting in the bottom of the closet bend that I am working on. That is the last fixture on the run and furthest away from the vertical stack.....about 5 feet.... It has always been this way and there has never been any problems with drainage or toilets flushing.....I discovered it after removing some sheetrock to fix the place up.......Even if I cut out the horizontal run...I would still have to use a banded rubber clamp on the vertical section and I would have the sme poor fit. The C.I. od is smaller than the PVC a little ....any tips would be appreciated....
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