What car are you in? I had this issue with my KE10, the bottom rad hoses are difficult to find (in a hurry), I use a chopped KE20 bottom hose.
I had the same issue, the later alternator fan blades nip the hose as the engine rocks. It eventually bit a pinhole in the hose after about 6 months of driving. I reckon I use an 845mm belt, I can't actually get the belt on without taking the waterpump pulley off, that's how short it is. Try that slightly smaller one, you can loosen the water pump pulley right off slip the belt over it and tighten it up to get it on.
Next time I pull the Rad out, I'll get the radiator outlet modified and turned 90 degrees and run a different hose.
Also, I made a very thin piece of stainless sheet and taped it onto the rad hose so if it touches it doesn't chop into the rubber.