I have an old toilet that was installed when my house was built 38 years ago. I don't know the make. I started having a intermittent flushing problem several months ago. I would flush and sometimes the water would just whirl around in the bowl but nothing would go down and out. I had a Korky flush valve that I thought might be at fault, so I replaced it with a newer Korky, since it worked well for me previously. I still have the same problem with the new valve. Here's what puzzles me. I don't remember what possessed me to try this a while back, but if I squirt some liquid dish washing detergent into the bottom exit part of the bowl, everything goes right down immediately, as it should. What might my flushing problem be and why does the liquid detergent work to make it flush properly? Thanks for any help you can give me here.