every time the washer drains through the waste line it ends up filling the sink. I really do think that the problem is because of the way the drain is built,I'm not a pluming expert nor close to one but just by the look of it is does not seam right.its an old house with a cast iron threaded nipple coming out the wall.a one and half p-trap connects to that,then a hub x hub long sweep comes next which leads to the sink drain,after that a piece of pipe extends straight up for the washer drain.I hope everyone can paint a pitcher of what I just said and give me a detail list of how to build a drain the right way . THANKS TO ALL WHO REPLY

How about a picture.

How about a picture. OK here is a drawing of it

Hi 7up

I can tell you that the drain(s) are definitely NOT piped correctly, but I also don't think this incorrectly piped drain is the issue. Instead, I'm quite sure that the drain line (after the PTRAP) is partially clogged. Here, you will need to snake the drain line or even better, cut the trap out and use a chisel and hammer to clean the clog up (pretty sure that you will find a super solid clog). We can discuss proper drain arrangement after you unclog the drain!

Care to discuss more? Let me know, OK?

Mark